Chronotherapeutic Drug Delivery System of Flurbiprofen

“DESIGN AND EVALUATION OF CHRONOTHERAPEUTIC

DRUG DELIVERY SYSTEM OF FLURBIPROFEN”

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Mr. VINAY KUMAR.K.V. B. Pharm., Reg. No.09PU334

Dissertation Submitted to the

Rajiv Gandhi University of Health Sciences, Karnataka, Bangalore

In partial fulfillment of the requirements for the degree of

MASTER OF PHARMACY

IN

PHARMACEUTICS

Under the guidance of

Dr. T. SIVAKUMAR M. Pharm., Ph.D.

Department of Pharmaceutics

Bharathi College of Pharmacy

Bharathinagara

2011

RAJIV GANDHI UNIVERSITY OF HEALTH SCIENCES,

KARNATAKA, BANGALORE

DECLARATION BY THE CANDIDATE

I hereby declare that the matter embodied in the dissertation

entitled hereby declare that the matter embodied in the dissertation

entitled “DESIGN AND EVALUATION OF CHRONOTHERAPEUTIC DRUG

DELIVERY SYSTEM OF FLURBIPROFEN” is a bonafide and genuine

research work carried out by me under the guidance of

Dr. T. Sivakumar M. Pharm., Ph.D., Department of Pharmaceutics,

Bharathi College of Pharmacy, Bharathinagara. The work embodied in

this thesis is original and has not been submitted the basis for the award

of degree, diploma, associate ship (or) fellowship of any other university

(or) institution.

Date:

Place: Bharathinagara Mr. VINAY KUMAR.K.V. B. Pharm.,

BHARATHI COLLEGE OF PHARMACY

BHARATHI NAGARA-571422

CERTIFICATE BY THE GUIDE

This is to certify that the dissertation entitled “DESIGN AND

EVALUATION OF CHRONOTHERAPEUTIC DRUG DELIVERY SYSTEM OF

FLURBIPROFEN” is a bonafide research work carried out by

Mr. VINAY KUMAR.K.V. submitted in partial fulfillment for the award

of the degree of “Master of Pharmacy” in pharmaceutics by the Rajiv

Gandhi University of health sciences, Karnataka, Bangalore.

Date: Dr. T. SIVAKUMAR M. Pharm., Ph. D. Professor and HOD,

Place: Bharathinagara Department of Pharmaceutics,

Bharathi College of Pharmacy,

Bharathinagara – 571422



ENDORSEMENT BY THE HEAD OF THE

DEPARTMENT




Mr. VINAY KUMAR.K.V. submitted in partial fulfillment for the award

of the degree of “Master of Pharmacy” in Pharmaceutics by the Rajiv

Gandhi University of Health Sciences, Bangalore, Karnataka. This work

was carried out by him in the library and laboratories of Bharathi

College of Pharmacy, under the guidance of Dr. T. Sivakumar M.Pharm.,

Ph.D. Department of Pharmaceutics, Bharathi College of Pharmacy,

Bharathinagara.

Date: Dr. T. SIVAKUMAR M. Pharm., Ph. D. Professor and HOD,

Place: Bharathinagara Department of Pharmaceutic

Bharathi College of Pharmacy,

Bharathinagara – 571422



ENDORSEMENT BY THE PRINCIPAL / HEAD OF THE

INSTITUTION




Mr. VINAY KUAMR.K.V. submitted in partial fulfillment for the award

of the degree of “Master of Pharmacy” in Pharmaceutics by the Rajiv

Gandhi University of Health Sciences, Karnataka, Bangalore. This work

was carried out by him in the library and laboratories of Bharathi

College of Pharmacy, under the guidance of Dr. T. Sivakumar M.Pharm.,

Ph.D. Department of Pharmaceutics, Bharathi College of Pharmacy,

Bharathinagara.

Date: Dr. T. TAMIZH MANI M. Pharm., Ph.D.

Principal,

Place: Bharathinagara Bharathi College of Pharmacy,

Bharathinagara – 571422.

COPYRIGHTCOPYRIGHTCOPYRIGHTCOPYRIGHT

DECLARATION BY THE CANDIDATE

I hereby declare that the Rajiv Gandhi University of Health

Sciences, Karnataka shall have the rights to preserve, use and

disseminate this dissertation / thesis in print or electronic format for

academic / research purpose.

Date:

Place: Bharathinagara Mr. VINAY KUMAR.K.V. B.Pharm.,

© Rajiv Gandhi University of Health Sciences, Karnataka.

ACKNOWLEDGEMENTACKNOWLEDGEMENTACKNOWLEDGEMENTACKNOWLEDGEMENT

I am thankful to the Almighty for blessing in successful completion of this

dissertation.

Many Thanks to Almighty God (Lord Hanuman, Lord Shiva, Lord

Kukke-Subramanyaswamy, Lord Lakshmi, Lord Saraswathi, Lord

Ganapathi) for it he who began this work in me and carried it to completion. It is

He who has blesses me with the people whose names I feel privileged to mention

here.

This M’Pharm makes me to suffer a lot (mentally,economically,emotionally)

because of one trustless friendship,because of that I lost trust in my family in all

the aspects,till today i suffers like anything and its difficult to overcome from

that,so I pray god to put fullstop for my worries as soon as possible.

I primarily thankful to say heartly thanful to my brother in law Mr.Praful

Chandra,for his encouragement throughout my M’pharm.

I consider it as a great privilege to express my heartfelt gratitude and sincere

thanks to my esteemed guide Dr. T .Sivakumar, Professor, Head of department of

Pharmaceutics, Bharathi college of pharmacy, Bharathinagara, for his valuable

suggestions, encouragement, motivation, guidance and co-operation during my

dissertation work.

I take this opportunity to express my thanks for Mrs. K. Kavitha, Assistant

professors, Dept. of Pharmaceutics, Bharathi College of Pharmacy,

Bharathinagara, for her support during my project.

I take this opportunity to express my thanks for Mr Ganesh, Assistant

professors, Dept. of Pharmaceutics, Bharathi College of Pharmacy,

Bharathinagara.

I taken this opportunity to express my regards to Dr. T. Tamizhmani,

Principal, Bharathi College of Pharmacy,Bharathinagara.

I am very much grateful to Micro Labs Bangalore, for providing me gift

sample of bulk drug for carriying out my project work.

I express my deep gratitude to, Mr.Rupesh kumar, Mr.shivkumar, Dr.Siju,

Mr. Jose gnana babu, Mrs. Sowjanya, and the entire staff of Bharathi College of

Pharmacy for the valuable guidance during the course of study.

“Friend in need are friends indeed”, I thank to my dearest friends

Chandrashekar, Challa Chenchi Reddy, Vinodkumar, Nitin, Anil kumar,

Chikkanumegowda, Madhusudhan, Poornachandra, Arjun, Umesh,

Balappa, Rakshith, KP, Shanthikumar, Pani, Kempegowda,

Srimanarayana , Sidhram, Harish, for their support in my life.

I specially convey my gratitude to my dearest classmates Pavan, Rajas,

Mangesh, Dipen, Sandeep, Mehaboob, Kiran, Mehul, and my college

collegues Shivraj, Selvam, Puneeth, Tanusha, for their timely help, support

and memorable company during this course

I was specially thankful to Mr.Tatiparthi Nagarjuna Reddy, for supporting

me to complete my dissertation work in the mean time.

I convey my special thanks to my dearest friend and my senior

Mr.Anil Kumar.S.N, for his valuable guidance and support during my course.

I heartly thankful to my dearest friend Mr.Vijay Kumar.V.N, for

supporting me to overcome from such a huge headache in my M’Pharm.

I thank specially to Puttamadu, satish, Sreenivas, Anil, Chandru,

Sathish, Cheluvegowda, Govinda, Siddhegowda, Shivlingegowda,

Doddaiah, Siddhaiah, and all the nonteaching staff for their friendly nature and

for their timely help.

I thankful to Mr.Nanda, Librarian for helping me a lot during my

M.Pharm, by providing necessary books, articles, journals in the mean time.

It is my privilege to utilize this golden moment and bow myself to

acknowledge my mother Mrs.Sundramma,my father Mr.VeereGowda.K, my

sister Mrs.Tanuja Praful Chandra,my brother in law Mr.Praful Chandra, and my

grand mother Mrs.Jayamma, for providing me an opportunity to pursue my

higher education along with their love and moral support..

At last but not least, I would like to express my thanks to Mr.B.Basavaraju,

Working president, Bharathi education trust, and Management of Bharathi

College of Pharmacy for providing necessary facilities during my course of study.

My Sincere thanks to all

Date:

Place: Bharathinagara. Mr.VINAY KUMAR.K.V B.Pharm,

DEDICATED TO MY

APPLE

RAHUL.P.HINDWAL

LIST OF ABBREVIATIONSLIST OF ABBREVIATIONSLIST OF ABBREVIATIONSLIST OF ABBREVIATIONS

Department Of Pharmaceutics, Bharathi College Of Pharmacy.Department Of Pharmaceutics, Bharathi College Of Pharmacy.Department Of Pharmaceutics, Bharathi College Of Pharmacy.Department Of Pharmaceutics, Bharathi College Of Pharmacy.

Abs : Absorbance

0C : Temperature on Celsius Scale

CAP : Cellulose Acetate Phthalate

Cm : Centimeter

cm2

: Centimeter square

Cps : Centipoises

oF : Temperature on Faranide Scale

FDA : Food and Drug Administration

Gms : Grams

HPMC : Hydroxy propyl methyl cellulose

Hrs : Hours

IP : Indian Pharmacopoeia

IR : Infrared

kg/cm2 : Kilogram per centimeter square

L.R. : Laboratory Grade

Mg : Milligram

µg/mcg : Microgram

Min : Minutes

mm : Millimetre

NSAID : Non-steroidal anti-inflammatory drug

Nm : Nanometre

P.G : Pharmaceutical Grade

‘R2’ : Regression Coefficient

LIST OF ABBREVIATIONS

LIST OF ABBREVIATIONSLIST OF ABBREVIATIONSLIST OF ABBREVIATIONSLIST OF ABBREVIATIONS

Department Of Pharmaceutics, Bharathi College Of Pharmacy.Department Of Pharmaceutics, Bharathi College Of Pharmacy.Department Of Pharmaceutics, Bharathi College Of Pharmacy.Department Of Pharmaceutics, Bharathi College Of Pharmacy.

Rpm : Resolutions per minute

SEM : Scanning Electron Microscopy

SD : Standard Deviation

UV : Ultraviolet

v/v : Volume/Volume

w/w : Weight/Weight

% w/v : Percentage weight by volume

% w/w : Percentage weight by weight

F1 : Flurbiprofen: Eudragit L-100: Eudragit S-100



F4: Flurbiprofen : Eudragit L-100: Eudragit S-100

F5 : Flurbiprofen : Eudragit L-100: Eudragit S-100: HPMC (20mg)

F6 : Flurbiprofen : Eudragit L-100: Eudragit S-100: HPMC (30mg)

F7: Flurbiprofen : Eudragit L-100: Eudragit S-100: HPMC (40mg)

ABSTRACTABSTRACTABSTRACTABSTRACT

Department of Pharmaceutics, BharathiDepartment of Pharmaceutics, BharathiDepartment of Pharmaceutics, BharathiDepartment of Pharmaceutics, Bharathi College of Pharmacy.College of Pharmacy.College of Pharmacy.College of Pharmacy.

In this study, investigation of an oral colon specific, pulsatile device to achieve

time and/or site specific release of Flurbiprofen, based on chrono-pharmaceutical

consideration. The basic design consists of an insoluble hard gelatin capsule body filled

with eudragit microspheres of Flurbiprofen and sealed with a HPMC plug. The entire

device was enteric coated, so that the variability in gastric emptying time can be

overcome and a colon-specific release can be achieved. The Flurbiprofen microspheres

were prepared by solvent evaporation method with Eudragit L-100 and S-100 (1:2) by

varying drug to polymer ratio and evaluated for the particle size, angle of repose,

percentage yield, drug content, SEM, IR and in-vitro release study. The cumulative %

release for F1, F2, F3 and F4 were found to be 95.91%, 92.06%, 89.17%, and 87.81% at

the end of 12th hr. From the obtained result formulation F3 was selected as an optimized

formulation for designing pulsatile device. A hydrogel polymer HPMC was used as plugs

in different ratios, to maintain a suitable lag period. The entire device was coated with

5% CAP. The formulated pulsatile device was evaluated weight variation, thickness of

CAP and in-vitro release study. The in-vitro release study were carried out using pH 1.2

buffer for a period of 2 hrs then 7.4 pH phosphate buffer for a period of 3hrs then 6.8 pH

phosphate buffer for a period of 10 hrs. At the end of 15th

hrs the drug release was of

75.96 %, 72.01 % and 59.92 % for F5, F6 and F7 respectively.

Keywords: Pulsatile; Colon-specific device: Chronotherapeutics: arthritis; Eudragit

microspheres.

ABSTRACT

CONTENTSCONTENTSCONTENTSCONTENTS

Department Department Department Department oooof Pharmacf Pharmacf Pharmacf Pharmaceutics, Bharathi College eutics, Bharathi College eutics, Bharathi College eutics, Bharathi College oooof Pharmacyf Pharmacyf Pharmacyf Pharmacy

Chapter

No. Title

Page

No.

1 Introduction 1

1.1 Circadian rhythms and their implications 2

1.2 Chronotherapeutic: therapy in synchrony with biorhythms 4

1.3 Arthritis 4

1.4 Chronopharmaceutics

9

1.5 Pulsatile drug delivery systems 10

1.6 Colon specific drug delivery systems (CSDDS) 15

1.7 Methods for targeting drug into the colon 17

2 Aims and Objectives 19

2.1 Plan of work 19

3 Review of literature 21

3.1 Drug profile 26

3.1.1 Flurbiprofen 26

3.2 Excipient profiles 28

3.2.1 Eudragit l 100 and Eudragit s100 28

3.2.2 Hydroxypropyl methylcellulose 29

CONTENTS

CONTENTSCONTENTSCONTENTSCONTENTS

Department Department Department Department oooof Pharmacf Pharmacf Pharmacf Pharmaceutics, Bharathi College eutics, Bharathi College eutics, Bharathi College eutics, Bharathi College oooof Pharmacyf Pharmacyf Pharmacyf Pharmacy

4 Materials and Methods 31

4.1 Materials 31

4.2 Methods 33

4.2.1 Preformulation studies 33

4.2.2 Preparation of Flurbiprofen microspheres 34

4.2.3 Evaluation of Flurbiprofen microspheres

36

4.2.4 Preparation of cross-linked gelatin capsules 37

4.2.5 Physical tests 38

4.2.6 Chemical tests 39

4.3 Formulation of pulsatile (modified pulsincap) drug

delivery system 40

4.3.1 Coating of pulsincap 40

4.3.2 Evaluation of modified pulsincap 41

5 Results 43

6 Discussion 64

7 Conclusion 70

8 Summary 71

9 Bibliography 73

10 Annexure 80

LIST OF TABLESLIST OF TABLESLIST OF TABLESLIST OF TABLES

Department of Pharmaceutics, Bharathi College oDepartment of Pharmaceutics, Bharathi College oDepartment of Pharmaceutics, Bharathi College oDepartment of Pharmaceutics, Bharathi College of Pharmacyf Pharmacyf Pharmacyf Pharmacy

Table

No. Title

Page

No.

1.1 Circadian rhythm and manifestation of clinical diseases 3

1.2 Average pH in the GI tract 16

1.3 Average GI transit time 17

1.4 Summary of colon-specific drug delivery strategies 18

4.1 Materials / Chemicals used 31

4.2 Equipments used and source 32

4.3

Formulation design of Flurbiprofen Microspheres using

Eudragit L-100 and Eudragit S-100

35

5.1

Standard calibration data of Flurbiprofen 1.2, 6.8 and 7.4

buffer at 247 nm

43

5.2 Micromeritic properties of Flurbiprofen Microspheres 46

5.3

Percentage yield and Drug content of Flurbiprofen

microspheres

47

5.4

In-vitro release profile of Flurbiprofen microspheres for

F1

48

5.5


F2

49

5.6


F3

50

5.7


F4

51

LIST OF TABLES

LIST OF TABLESLIST OF TABLESLIST OF TABLESLIST OF TABLES

Department of Pharmaceutics, Bharathi College oDepartment of Pharmaceutics, Bharathi College oDepartment of Pharmaceutics, Bharathi College oDepartment of Pharmaceutics, Bharathi College of Pharmacyf Pharmacyf Pharmacyf Pharmacy

5.8

Kinetic values obtained from in-vitro release profile for

microspheres

52

5.9

Composition for modified pulsatile device on the basis of

design summary

56

5.10 Coating thickness 57

5.11 Weight variation 57

5.12

In-vitro release rate profile of F5 containing 20mg

HPMC

58

5.13


HPMC

59

5.14


HPMC

60

5.15

Kinetic values obtained from in-vitro release profile for

microspheres

61

LIST OF FIGURESLIST OF FIGURESLIST OF FIGURESLIST OF FIGURES

Department Department Department Department oooof Pharmaceutics, Bharathi College f Pharmaceutics, Bharathi College f Pharmaceutics, Bharathi College f Pharmaceutics, Bharathi College oooof Pharmacyf Pharmacyf Pharmacyf Pharmacy

Fig. No. Title Page No.

1.1

A 24-hours clock diagram of the peak time of selected

human circadian rhythms with reference to the day-night

cycle.

3

1.2 Drug release profile of pulsatile drug delivery systems 12

1.3 Different stages in drug release from pulsincap 14

1.4 Structure of colon 16

4.1 Overview of designed pulsatile device 41

5.1 Standard calibration curve of Flurbiprofen in pH 1.2

buffer

43


buffer

44


buffer

44

5.4 I.R. Spectrum of Flurbiprofen (pure drug) 45

5.5 I.R. Spectrum of physical mixture of Flurbiprofen and

polymers

45

5.6

Images of Flurbiprofen microspheres for F1, F2, F3 and

F4

46

LIST OF FIGURES

LIST OF FIGURESLIST OF FIGURESLIST OF FIGURESLIST OF FIGURES

Department Department Department Department oooof Pharmaceutics, Bharathi College f Pharmaceutics, Bharathi College f Pharmaceutics, Bharathi College f Pharmaceutics, Bharathi College oooof Pharmacyf Pharmacyf Pharmacyf Pharmacy

5.7 Scanning electron microphotographs of F3 formulation 47

5.8 Cumulative % release of Flurbiprofen microspheres

52

5.9 Zero order plots of Flurbiprofen microspheres 53

5.10 First order plots of Flurbiprofen microspheres 53

5.11 Higuchi diffusion plots of Flurbiprofen microspheres 54

5.12 Peppas exponentional plots of Flurbiprofen microspheres 54

5.13

I.R. Spectrum of physical mixture of Flurbiprofen and

HPMC

56

5.14

Cumulative % release of Flurbiprofen microspheres

containing HPMC as hydrogel plug 61

5.15

Zero order plots of formulation containing HPMC as

hydrogel plug

62

5.16

First order plots of formulation containing HPMC as

hydrogel plug

62

5.17

Higuchi diffusion plots of formulation containing HPMC

as hydrogel plug

63

5.18

Peppas exponentional plots of formulation containing

HPMC as hydrogel plug

63

CHAPTER 1 CHAPTER 1 CHAPTER 1 CHAPTER 1 IIIINTRODUCTIONNTRODUCTIONNTRODUCTIONNTRODUCTION

Department Department Department Department oooof Pharmaceutics, Bharathi College f Pharmaceutics, Bharathi College f Pharmaceutics, Bharathi College f Pharmaceutics, Bharathi College oooof Pharmacy.f Pharmacy.f Pharmacy.f Pharmacy. 1111

Controlled drug delivery systems have acquired a centre stage in the area of

pharmaceutical R &D sector. Such systems offer temporal and/or spatial control over the

release of drug and grant a new lease of life to a drug molecule in terms of controlled

drug delivery systems for obvious advantages of oral route of drug administration. These

dosage forms offer many advantages, such as nearly constant drug level at the site of

action, prevention of peak-valley fluctuation, reduction in dose of drug, reduced dosage

frequency, avoidance of side effects and improved patient compliance. In such systems

the drug release commences as soon as the dosage form is administered as in the case of

conventional dosage forms. However, there are certain conditions, which demand release

of drug after a lag time. Such a release pattern is known as “pulsatile release”.1

However, the major bottleneck in the development of drug delivery systems that

match circadian rhythms (chronopharmaceutical drug delivery system: ChrDDS) may be

the availability of appropriate technology. The diseases currently targeted for

chronopharmaceutical formulations are those for which there are enough scientific

backgrounds to justify ChrDDS compared to the conventional drug administration

approach. These include asthma, arthritis, duodenal ulcer, cancer, diabetes,

cardiovascular diseases, hypercholesterolemia, ulcer and neurological diseases.2

,3.

Circadian variation in pain, stiffness and manual and manual deyterity in patients

with osteo and rheumatoid arthritis have been studied and has implication for timing

antirheumatoid drug treatment.4

Chronopharmacotherapy for rheumatoid arthritis has

been recommended to ensure that the highest blood levels of the drug coincide with peak

1. INTRODUCTION



pain and stiffness.5 A pulsatile drug delivery system that can be administered at night

(before sleep) but that release drug in early morning would be a promising

chronopharmaceutic system.5,6

Drug targeting to colon would prove useful where intentional delayed drug

absorption is desired from therapeutic point of view in the treatment of disease that have

peak symptoms in the early morning such as nocturnal asthma, angina, arthritis.1,4,7,8,

1.1 CIRCADIAN RHYTHMS AND THEIR IMPLICATIONS

Circadian rhythms are self-sustaining, endogenous oscillation, exhibiting

periodicities of about one day or 24 hours. Normally, circadian rhythms are synchronized

according to the body’s pacemaker clock, located in the suprachiasmic nucleus of the

hypothalamus.

The physiology and biochemistry of human being is not constant during the 24

hours, but variable in a predictable manner as defined by the timing of the peak and

through of each of the body’s circadian processes and functions. The peak in the rhythms

of basal gastric and secretion, white blood cells (WBC), lymphocytes, prolactin,

melatonin, eosinophils, adrenal corticotrophic hormone (ACTH), follicle stimulating

hormone (FSH), and leuteinizing hormone (LH), is manifested at specific times during

the nocturnal sleep span. The peak in serum cortisol, aldosterone, testosterone plus

platelet adhesiveness and blood viscosity follows later during the initial hours of diurnal

activity. Hematocrit is the greatest and airway caliber the best around the middle and

afternoon hours, platelet numbers and uric acid peak later during the day and evening.

Hence, several physiological processes in humans vary in a rhythmic manner, in

synchrony with the internal biological clock as shown in Fig.1.14,9



Figure 1.1: A 24-hours clock diagram of the peak time of selected human circadian

rhythms with reference to the day-night cycle.

Table 1.1: Circadian rhythm and manifestation of clinical diseases

Disease or syndrome Circadian rhythmicity

Allergic Rhinitis Worse in the morning/upon rising

Asthma Exacerbation more common during the sleep period

Rheumatoid Arthritis Symptoms more common during the sleep period

Osteoarthritis Symptoms worse in the middle/later portion of the day

Myocardial Infraction Incidence greatest in early morning

Stroke Incidence higher in the morning

Sudden cardiac death Incidence higher in the morning after awakening

Peptic ulcer disease Worse in late evening and early morning hours



1.2 CHRONOTHERAPEUTIC: THERAPY IN SYNCHRONY WITH

BIORHYTHMS

Chronotherapy coordinates drug delivery with human biological rhythms and

holds huge promise in areas of pain management and treatment of asthma, heart disease

and cancer. The coordination of medical treatment and drug delivery with such biological

clocks and rhythms is termed chronotherapy.10

The goal of chronotherapeutics is to synchronize the timing of treatment with the

intrinsic timing of illness. The chronotherapy of a medication may be accomplished by

the judicious timing of conventionally formulated tablets and capsules. In most cases,

however, special drug delivery technology must be relied upon to synchronize drug

concentrations to rhythms in disease activity.4

1.3 ARTHRITIS 11, 12, 13

The term arthritis is used to describe changes in the joints which may be either

inflammatory or degenerative in character. If only one joint is affected the condition is

referred to as monoarticular arthritis; if several joints are involved it is called

polyarticular arthritis or polyarthritis (Greek: poly= many).

Symptoms of arthritis:

• The joints ache and swell

• Pain and muscle-spasm are common features; and in the late stages very severe pain

and gross destruction and deformity of the joints may develop.

• In children the condition tends to develop suddenly, many joints being affected from

the beginning the small joint soft the hands and feet being as a rule affected first.

• Severe muscle wasting might also take place



• Patients of arthritis can only walk a certain distance after which they tend to feel pain

and stiffness in their joints.

• Arthritis can also develop slowly starting as a slight restriction of movement in

certain directions, with stiffness first thing in the morning and aches after

exercises.

• Arthritis can be both of the infective variety as well as the chronic.

• In infective arthritis the patient feels ill and toxic with a swinging temperature and a

furred tongue. Leucocytes are always evident, and a blood culture may confirm

the presence of the septicaemia.

Some common forms of Arthritis:

• Rheumatic arthritis(fibromyalgia)

• Rheumatoid arthritis(Still's Disease)

• Degenerative, e.g. osteo-arthritis

• Psoriatic arthritis

• Ankylosing Spondylitis

Rheumatoid Arthritis:

Rheumatoid arthritis is a form of chronic arthritis. This disease affects chiefly

young adults, mainly women, and one or many joints may be involved; it also occurs in

children (Still's Disease). It is generalized affection of joints, and their synovial

membranes, cartilages, capsules and the muscles supplying them; but other connective

tissues elsewhere in the body might also be affected. Rheumatoid arthritis is now a major

cause of crippling in European countries, but it is not common in the tropics.



Causes of Rheumatoid Arthritis:

The causes of the conditions are not yet fully understood. While infection form

the focus of the respiratory, alimentary, urinary or genital tracts is sometimes a factor,

recent research has also demonstrated the importance of the endocrine glands as both as a

cause and a therapy.

Causes of osteoarthritis:

• This disease is caused due to a gradual destruction of cartilage. Its precise cause is

unknown but it is no longer known as a simple wear and tear disease.

• Hereditary seems to play a very important role in osteoarthritis.

• How can an osteoarthritis patient be treated?

• The treatment of osteoarthritis is simpler than that of the more severe forms of

arthritis.

Fibromyalgia

Fibromyalgia is a common condition. However it can get severe enough to start

intruding into your day to day life. Fibromyalgia literally means, fibrous tissues (fibro-)

and the muscles (-my-) being affected by pain (-algia). In this disease the whole body

feels affected since the tendons and the ligaments both get affected. Fibromyalgia in fact

affects the muscles and not the joints at all. Also, this form of arthritis never causes

permanent damage to tissues though the symptoms may last for months or years.

Causes fibromyalgia:

• Fibromyalgia is a functional disturbance which implies that its causes cannot purely

be categorized as being physical or mental.

Both the person's mind as well as body is involved in this ailment.



• Sleep being vital to both the good health of the body as well as the mind, it comes as

no surprise that a major cause of fibromyalgia is sleep disorders.

• If a person has more light sleep than deep sleep then he is likely to be inflicted by

Fibromyalgia.

Ankylosing Spondylitis

This is a chronic inflammatory form of arthritis which affects the spinal joints.

The main and the most important feature is that in this form of arthritis the joints between

the spine and the pelvis get inflicted. This form of arthritis causes back ache and stiffness

in the back as well as a hunched up body posture. In very severe cases there might be

inflammations around the tendons and ligaments that connect and provide support to

joints that lead to pain and tenderness in the shoulder blades and the spinal cord.

Ankylosing Spondylitis can also impair mobility by creating inflammation of the

vertebra.

This ailment can have confusing symptoms since there can be varied kinds of

manifestations. While some individuals suffer gouts of transient back ache only while

others suffer chronic back aches that lead to differing degrees of back ache and stiffness.

Colloquially, Ankylosing Spondylitis is referred to as poker back and rheumatoid

Spondylitis. It is only about five decades back that this ailment got the name that is now

prevalent. Since this ailment belongs to the family of diseases that attack the spine it is

also referred to as, in medical jargon as spondylarthropathies.

You must keep in mind that men are three times more at a risk of acquiring this

disease than women. This ailment also attacks youngster’s more than older people,

contrary to popular belief.



Causes Ankylosing Spondylitis:

• Ankylosing spondylitis is believed to be hereditary since it depends on tissue type and

we genetically inherit tissue types.

• The exact cause of this ailment is however still not known.

• Some researchers also believe that environmental interaction with certain tissue types

might result in Ankylosing spondylitis.

Psoriatic arthritis

Psoriatic arthritis is a less common form of arthritis which affects, men and

women in an equal ratio, and usually strikes when they are between the ages of 20 to 50.

It is marked by scaly growth of rough tissues around the joints. There are several types of

psoriatic arthritis, with symptoms that range from mild to severe. In general, the disease

isn't as crippling as other forms of arthritis, but if left untreated it can cause discomfort,

disability and deformity. Although no cure exists for psoriatic arthritis, medication,

physical therapy and lifestyle changes often can relieve pain and slow the progression of

joint damage. Psoriatic arthritis causes swelling in the joints. It affects a number of joints

including the fingers, wrists, toes, knees, ankles, elbows and shoulder joints, the spine

and joints in the lower back (called sacroiliac joints). Psoriatic arthritis also affects tissues

surrounding the joints including tendons and ligaments and causes inflammation and

swelling and pain in and around the joints. This ailment usually affects the wrists, knees,

ankles, fingers and toes. It also affects the back. One of these conditions is psoriatic

arthritis, which may affect as many as 1 million of the approximately 6 million

Americans who have psoriasis. In fact 30% of the people who have psoriasis later go onto

have psoriatic arthritis.



Causes of Psoriatic arthritis:

• The exact cause of psoriatic arthritis is unknown

• As mentioned before psoriasis generally develops into psoriatic arthritis

• It has been observed that people who have psoriatic arthritis patients in the house

generally get inflicted by this ailment.

• Exposure to infection, stress, alcohol, poor nutrition

• Reaction to a medication or vaccine

• Overexposure to the sun or prolonged exposure to irritating chemical such as

disinfectants and pain thinners.

1.4 CHRONOPHARMACEUTICS2

Chronopharmaceutics is a branch of pharmaceutics devoted to design and

evaluation of drug delivery system that release a bioactive agent at a rhythm that ideally

matches the biological requirement of a given disease therapy. Ideally

chronopharmaceutical drug delivery system (ChrDDS) should embody time-controlled

and site specific drug delivery system. Evidence suggests that an ideal ChrDDS should:

• Be non-toxic within approved limits of use,

• Have a real-time and specific triggering biomarker for a given disease state.

• Have a feed-back control system (ex: self-regulated and adaptive capability to

circadian rhythm and individual patient to differentiate between awake-sleep status),

• Be biocompatible and biodegradable, especially for parentral administration,

• Be easy to manufacture at economic cost and

• Be easy to administer to patients and enhances compliance to dosage regimen.



1.5 PULSATILE DRUG DELIVERY SYSTEMS

Among modified-release oral dosage forms, increasing interest has currently

turned to systems designed to achieve time specific (delayed, pulsatile) and site-specific

delivery of drugs. In particular, systems for delayed release are meant to deliver the

active principle after a programmed time period following administration. These systems

constitute a relatively new class of device the importance of which is especially

connected with the recent advances in chronopharmacology. It is by now well-known that

the symptomatology of a large number of pathologies as well as the pharmacokinetics

and pharmacodynamics of several drugs follow temporal rhythms, often resulting in

circadian variations.

Therefore, the possibility of exploiting delayed release to perform chronotherapy

is quite appealing for those diseases, the symptoms of which recur mainly at night time or

in the early morning, such as bronchial asthma, angina pectoris and rheumatoid arthritis.

The delay in the onset of release has so far mainly been achieved through osmotic

mechanisms, hydrophilic or hydrophobic layers, coating a drug-loaded core and swellable

or erodible plugs sealing a drug containing insoluble capsule body.14

Delivery systems with a pulsatile release pattern are receiving increasing interest

for the development of dosage forms, because conventional systems with a continuous

release are not ideal. Most conventional oral controlled release drug delivery systems

release the drug with constant or variable release rates. A pulsatile release profile is

characterized by a time period of no release rates (lag time) followed by a rapid and

complete release.



These dosage forms offer many advantages such as

• Nearly constant drug levels at the site of action.

• Avoidance of undesirable side effects.

• Reduced dose andImproved patient compliance.

• Used for drugs with chronopharmacological behaviour, a high first pass effect, the

requirement of night-time dosing and site-specific absorption in GIT.

The conditions that demand pulsatile release include:

• Many body functions that follow circadian rhythm i.e. their waxes and wanes with

time. Ex: hormonal secretions.

• Diseases like bronchial asthma, myocardial infraction, angina pectoris, rheumatoid

diseases, ulcer and hypertension display time dependence.

• Drugs that produce biological tolerance demand for a system that will prevent

continuous present at the biophase as this tend to reduce their therapeutic effect.

• The lag time is essential for the drugs that undergo degradation in gastric acidic

medium (ex: peptide drugs) irritate the gastric mucosa or induce nausea and vomiting.

• Targeting to distal organs of GIT like the colon requires that the drug release is

prevented in the upper two-third portion of the GIT.

All of these conditions demand for a time-programmed therapeutic scheme

releasing the right amount of drug at the right time. This requirement is fulfilled by

pulsatile drug delivery system, which is characterized by a lag time that is an interval of

no drug release followed by rapid drug release.1

Pulsatile systems are basically time-controlled drug delivery systems in which the

system controls the lag time independent of environmental factors like pH, enzymes,



gastrointestinal motility, etc. these time-controlled systems can be classified as single unit

(tablet or capsule) or multiple unit (e.g., pellets) systems as shown in the Fig 1.2.1,15

Figure 1.2: Drug release profile of pulsatile drug delivery systems

A: Ideal sigmoidal release, B, C: Delayed release after initial lag time

1) Single Unit Systems15,16,17,18

i) Drug delivery systems with eroding or soluble barrier coatings

Most pulsatile delivery systems are reservoir devices coated with a barrier layer.

The barrier dissolves or erodes after a specify lag period, after which the drug is released

rapidly from the reservoir core.

ii) Drug delivery systems with rupturable coatings

In this the drug is released from a core (tablet or capsule) after rupturing the

surrounding polymeric layer, caused by inbuilt pressure within the system. The pressure

necessary to rupture the coating can be achieved with gas-producing effervescent

excipients, osmotic pressure or swelling agents.



iii) Capsular shaped systems

Several single unit pulsatile dosage forms with a capsular design have been

developed. Most of them consist of an insoluble capsule body, containing the drug and a

plug, which gets removed after a predetermined lag time because of swelling, erosion or

dissolution. E.g., Pulsincap®

system and Port®

system.

The Pulsincap®

system consists of a water-insoluble capsule body (exposing the

body to formaldehyde vapor which may be produced by the addition of trioxymethylene

tablets or potassium permanganate to formalin or any other method), filled with the drug

formulation and plugged with a swellable hydrogel at the open end. Upon contact with

dissolution media or gastrointestinal fluid, the plug swells and comes out of the capsule

after a lag time, followed by a rapid release of the contents. The lag time prior to the drug

release can be controlled by the dimension and the position of the drug. In order to assure

a rapid release of the drug content, effervescent agents or disintegrants were added to the

drug formulation, especially with water-insoluble drug. Studies in animals and healthy

volunteers proved the tolerability of the formulation (e.g., absence of gastrointestinal

irritation). In order to overcome the potential problem of variable gastric residence time

of a single unit dosage forms, the Pulsincap®

system was coated with an enteric layer,

which dissolved upon reaching the higher pH regions of the small intestine. Different

stages in drug release from pulsincap was shown in Fig 1.3.

CHAPTER 1 CHAPTER 1 CHAPTER 1 CHAPTER 1

Department Department Department Department oooof Pharmaceutics, Bharathi College f Pharmaceutics, Bharathi College f Pharmaceutics, Bharathi College f Pharmaceutics, Bharathi College

Figure 1.3

The plug consists of

• Swellable materials coated with insoluble, but permeable polymers (e.g.,

polymethacrylates)

• Erodible compressed

• Congealed melted polymers (e.g., saturated polyglycoated glycerides or glyceryl

monooleate).

2) Multiparticulate Pulsatile Drug Delivery Systems:

These have various advantages,

which include, a reproducible gastric residence time, no risk of dose dumping and the

flexibility to blend with different compositions or release patterns e.g., pellets.

However, drug loading in these systems is

excipients (e.g. sugar cores). Multiparticulate with pulsatile release profiles are usually

reservoir-type devices with a coating, which either ruptures or changes its permeability.


f Pharmaceutics, Bharathi College f Pharmaceutics, Bharathi College f Pharmaceutics, Bharathi College f Pharmaceutics, Bharathi College oooof Pharmacy.f Pharmacy.f Pharmacy.f Pharmacy.

Figure 1.3: Different stages in drug release from pulsincap

Swellable materials coated with insoluble, but permeable polymers (e.g.,

Erodible compressed materials (e.g., HPMC, polyvinyl alcohol, polyethylene oxide)

Congealed melted polymers (e.g., saturated polyglycoated glycerides or glyceryl

2) Multiparticulate Pulsatile Drug Delivery Systems:

These have various advantages, when compared to single unit dosage forms,



However, drug loading in these systems is low because of higher need of


type devices with a coating, which either ruptures or changes its permeability.

IIIINTRODUCTIONNTRODUCTIONNTRODUCTIONNTRODUCTION

14141414

Different stages in drug release from pulsincap

Swellable materials coated with insoluble, but permeable polymers (e.g.,

materials (e.g., HPMC, polyvinyl alcohol, polyethylene oxide)

Congealed melted polymers (e.g., saturated polyglycoated glycerides or glyceryl

when compared to single unit dosage forms,



low because of higher need of


type devices with a coating, which either ruptures or changes its permeability.



1.6 COLON SPECIFIC DRUG DELIVERY SYSTEMS (CSDDS) 16, 17

The colonic region of the gastrointestinal tract is one area that would benefit from

the development and use of such modified release technologies. Although considered by

many to be an innocuous organ that has simple functions in the form of water and

electrolyte absorption and the formation, storage and expulsion of faecal material, the

colon is vulnerable to a number of disorders including ulcerative colitis, crohn’s disease

IBS and carcinomas. In addition, systemic absorption from the colon also be used as a

means of achieving chronotherapy for diseases that are sensitive to circadian rhythms

such as asthma, angina and arthritis.

Structure and function of the Colon16

The colon forms the lower part of the gastrointestinal tract and extends from the

ileocecal junction at the anus. The colon is upper five feet of the large intestine and the

rectum is the lower six inches. While the colon is mainly situated in the abdomen, the

rectum is primarily a pelvic organ. As shown in the Fig 1.4, the first portion of the colon

is spherical and is called cecum. The appendix hangs off the cecum. The next portion of

the colon, in the order in which contents flow, is the ascending (proximal) colon, just

under the liver, the angle or bend is known as the hepatic flexure, located just beneath the

rib cage. The colon then turns to a long horizontal segment, the transverse colon. Beneath

the left rib cage, the colon turns downward at the haustra, to become the descending

(distal) colon. In the left lower portion of the abdomen, the colon makes an S-shaped

curve from the hip over the midline known as the sigmoid colon. The colon and rectum

have an anatomic blood supply. Along these blood vessels are lymph nodes. Lymph


Department Department Department Department oooof Pharmaceutics, Bharathi College f Pharmaceutics, Bharathi College f Pharmaceutics, Bharathi College f Pharmaceutics, Bharathi College

nodes are structures found in the circulating

and store cells that fight infection, inflammation, foreign proteins and cancer.

pH in colon:7,16

Radiotelemetry shows the highest pH levels (7.5

entry into the colon, the pH drops to 6.4

the left colon 7.0±0.7. There is a fall in pH on entry into the colon due to the presence of

short chain fatty acids arising from bacterial fermentation polysaccharide

Location

Oral cavity

Oseophagus

Stomach

Small intestine

Large intestine


f Pharmaceutics, Bharathi College f Pharmaceutics, Bharathi College f Pharmaceutics, Bharathi College f Pharmaceutics, Bharathi College oooof Pharmacy.f Pharmacy.f Pharmacy.f Pharmacy.

nodes are structures found in the circulating lymphatic system of the body that produce


Figure 1.4: Structure of colon

Radiotelemetry shows the highest pH levels (7.5±0.5) in the terminal ileum. On

entry into the colon, the pH drops to 6.4±0.6. The pH in the mid colon is 6.6

0.7. There is a fall in pH on entry into the colon due to the presence of

short chain fatty acids arising from bacterial fermentation polysaccharide

Table 1.2: Average pH in the GI tract

pH

6.2-7.4

5.0-6.0

Fasted condition:1.5-2.0, Fed condition: 3.0

Jejunum:5.0-6.5, Ileum: 6.0-7.5

Right colon: 6.4, Mild colon and left colon:6.0

IIIINTRODUCTIONNTRODUCTIONNTRODUCTIONNTRODUCTION

16161616

lymphatic system of the body that produce


0.5) in the terminal ileum. On

0.6. The pH in the mid colon is 6.6±0.8 and in

0.7. There is a fall in pH on entry into the colon due to the presence of

short chain fatty acids arising from bacterial fermentation polysaccharides.

Fed condition: 3.0-7.5

colon:6.0-7.6



Gastrointestinal transit:7

Gastric emptying of dosage form is highly variable and depends primarily on

whether the subject is fed or fasted and on the properties of the dosage forms such as size

and density. The arrival of an oral dosage form at the colon is determined by the rate of

gastric emptying and the small intestinal transit time. Although the surface area in the

colon is low compared to the small intestine, this is compensated by the markedly slower

rate of transit.

Table 1.3: Average GI transit time

Oral Transit time (hr)

Stomach <1(fasting);>3(fed)

Small intestine 3-4

Large intestine 20-30

1.7 METHODS FOR TARGETING DRUG INTO THE COLON7,14,16,19,20

These applications are either drug specific (prodrug) or formulations specific

(coated or matrix preparations). The most commonly used targeting mechanisms are:

1 pH-dependent delivery

2 Time dependent delivery

3 Pressure dependent delivery

4 Bacteria- dependent delivery

The possibility of exploiting delayed release to perform chronotherapy, is quite

appealing for those diseases, the symptoms of which recur mainly at night time or in

the early morning, such as bronchial asthma, angina pectoris and rheumatoid

arthritis.21,22,23,24

.



Table 1.4: Summary of colon-specific drug delivery strategies16,19,20

Design

strategy Drug release triggering

mechanisms Advantages Disadvantages

Prodrugs

Cleavage of the linkage

bond between drug and

carrier via reduction and

hydrolysis by enzyme from

colon bacteria. Typical

enzymes include

azoreductase, glycosidase,

and glucuronidase.

Able to achieve

site specificity.

It will be considered as a

new chemical entity

from regulatory

prespective. So far this

approch has been

primarily constricted to

achives releated to the

treatment of IBD.

pH-

depedent

systems

Combination of polymers

with pH-dependent

solubility to take advantage

of the pH changes along the

GI tract.

Formulation

well protected

in the stomach

Unpredictable site-

specificity of drug

release because of

inter/intra subject

variation of pH between

small intestine and the

colon.

Time-

dependent

system

The onset of drug release is

aligned with positioning the

delivery system in the colon

by incorporating a time

factor simulating the system

transit in upper GIT.

Small intestine

transit time

fairly

consistent.

Substantial variation in

gastric retention times

make it complicated in

predicting the accurate

location of drug release.

Microfloro

activated

system

Primarily fermentation of

non-starch polysaccharides

by colon anaerobic bacteria.

The polysaccharides are

incorporated into the

delivery system via film

coating and matrix

formation.

Good site

specificity with

prodrugs and

polysaccharides.

Diet and disease can

affect colonic

microflora; enzymatic

degredation may be

excessively slow.

In this work Flurbiprofen was selected for dosage development. Flurbiprofen

[1,1’-biphenyl]-4-acetic acid, 2-fluoro-alpha-methyl-, is an important analgesic and

non-steroidal anti-inflammatory drug (NSAID) also with anti-pyretic properties whose

mechanism of action is the inhibition of prostaglandin synthesis. It is used in the

therapy of rheumatoid disorders. The drug must be administered approximately 150-

200mg daily by oral in divided doses.25

CHAPTER 2 CHAPTER 2 CHAPTER 2 CHAPTER 2 AIMS ANDAIMS ANDAIMS ANDAIMS AND OBJEOBJEOBJEOBJECTIVES CTIVES CTIVES CTIVES

Department of Pharmaceutics, Bharathi College of Pharmacy.Department of Pharmaceutics, Bharathi College of Pharmacy.Department of Pharmaceutics, Bharathi College of Pharmacy.Department of Pharmaceutics, Bharathi College of Pharmacy. 19191919

To design and characterize an oral, drug delivery system of Flurbiprofen intended

to approximate the chronobiology of arthrities, proposed for colonic targeting. It is a

chronopharmaceutical approach for the better treatment of rheumatoid arthritis. Based on

the concept that a formulation on leaving the stomach, arrives at the ileocaecal junction in

about 6 hours after administration and difference in pH throughout GIT, a time and pH

dependent pulsatile (or modified pulsincap), controlled drug delivery system was

designed. This capsule consists of a non-disintegrating body and a soluble cap. The drug

formulations is contained within the capsule body and separated from the water-soluble

cap by a hydrogel polymer plug. The entire capsule is enteric coated to prevent variable

gastric emptying. The enteric coating prevents disintegration of the soluble cap in the

gastric fluid. On reaching the small intestine the capsule will lose its enteric coating and

the polymer plug inside the capsule swells to create a lag phase that equals the small

intestinal transit time. This plug ejects on swelling and releases the drug from the capsule

in the colon.

2.1 PLAN OF RESEARCH WORK

� Preformulation studies:

• Selection of polymer and its combinations suitable for the colonic drug delivery

• Preparation of standard graph of Flurbiprofen using spectrometric methods.

• Drug-polymer Interaction

� Experimental designing for formulation and evaluation of Flurbiprofen microspheres:

• Preparation of Flurbiprofen microspheres by emulsification-solvent evaporation.

2. AIMS AND OBJECTIVES

CHAPTER 2 CHAPTER 2 CHAPTER 2 CHAPTER 2 AIMS ANDAIMS ANDAIMS ANDAIMS AND OBJEOBJEOBJEOBJECTIVES CTIVES CTIVES CTIVES

Department of Pharmaceutics, Bharathi College of Pharmacy.Department of Pharmaceutics, Bharathi College of Pharmacy.Department of Pharmaceutics, Bharathi College of Pharmacy.Department of Pharmaceutics, Bharathi College of Pharmacy. 20202020

� Evaluation of physicochemical parameters of Flurbiprofen microspheres.

• Particle size and flow property.

• Percentage yield

• Drug content uniformity

• Surface topography by SEM

• In vitro release studies

• Release kinetics

� Development and evaluation of modified pulsincap formulation:

• Formaldehyde treatment of capsule bodies.

• Selection of swellable polymer for the hydrogel plug. The concentration and selection

of hydrogel is such that it takes a particular time period (small intestinal time of 3-4

hrs) to be ejected out and release the drug in the colon.

• Formulation of modified pulsincap.

• Evaluation of the dosage forms for their physicochemical parameters, in vitro release

rate and release kinetics.

CHAPTER 3 CHAPTER 3 CHAPTER 3 CHAPTER 3 REVIEW OF LITERATUREREVIEW OF LITERATUREREVIEW OF LITERATUREREVIEW OF LITERATURE

Department of Pharmaceutics, Bharathi College of Department of Pharmaceutics, Bharathi College of Department of Pharmaceutics, Bharathi College of Department of Pharmaceutics, Bharathi College of PharmacyPharmacyPharmacyPharmacy 21212121

Listair CR et al., 26

developed a chronopharmaceutical capsule drug delivery system

capable of releasing drug after predetermined time delays. The drug formulation is sealed

inside the capsule body by an erodible table (ET). The release time is determined by an

ET erosion rate and increases as the content of an insoluble excipient (dibasic calcium

phosphate) and of gel forming excipient (HPMC) increases.

Samantha MK et al., 27

designed and evaluated Pulsincap drug delivery system of

Salbutamol sulphate for drug targeting to colon in disease condition like asthma. The in-

vitro dissolution studies indicated that the onset of drug release was after 7 to 8 hrs of the

experiment and revealed its better sustaining efficacy over a period of 24hrs.

Young-II Jeong et al., 28

evaluated pressure-controlled colon delivery (PCDCS) capsules

prepared by a dipping method. By consequently dipping in an ethanolic EC solution and

alkalized enteric polymer solution, PCDCS were obtained after both the capsule body and

cap were adjusted to the size of #2 capsules.

Seshasayan A et al., 29

studied release of Rifampicin from modified pulsincap

preparation, using different preparation of various hydrophilic polymer such as guar gum,

cabapol-940, sodium alginate, hydroxypropyl methylcellulose, gum karaya and poly

vinyl alcohol. Among all the polymers tested guar gum showed better sustaining capacity

even at low concentration.

3. REVIEW OF LITERATURE



Sangalli ME et al., 30

performed in-vitro and in-vivo evaluation of an oral system

(ChronotropicTM) designed to achieve time & /or site specific release. Cores containing

antipyrine as the model drug were prepared by tableting and both the retarding and

enteric coatings were applied in fluid bed.

Zahirul Khan MI et al., 31

formulated a pH-dependent colon targeted oral drug delivery

system using methacrylic acid copolymers. Drug release was manipulated using

Eudragit® 100-55 and Eudragit® S100 combinations. The coated tablets were tested in-

vitro for their sutability for pH dependent colon targeted oral delivery.

Howard Stevens NE et al., 32

designed pulsincap® formulations to deliver a dose of

drug following 5 h delay and evaluated the capability of the formulation to deliver

defetilide to the lower GIT. The combination of scintigraphic and pharmacokinetic

analysis permits identification of the site of drug release from the dosage form and

pharmacokinetic parameters to be studied in man in a noninvasive manner.

Libo Yang et al., 33

reviewed the new approaches in-vitro and in-vivo evaluation of colon

specific drug delivery systems.

Ying-huan Li et al., 34

developed a multifunctional and multiple unit system, which

contains versatile mini-tablets in a hard gelatin capsule, as Rapid release Mini-tablets

(RMTs), Sustained-release Mini-Tablets (SMTs), Pulsatile Mini-Tablets (PMTs) and

Delayed onset Sustained- release Mini tablets (DSMTs), each with various lag times of

release.

Tomohiro Takaya et al., 35

studied the importance of dissolution process on systemic

availability of drugs delivered by colon delivery system. The relationship between in-



vitro drug release characteristics from colon delivery systems and in-vivo drug absorption

was investigated using three kinds of delayed-release systems. Pressure controlled colon

delivery capsules for liquid preparations, time controlled colon delivery capsules for

liquid and solid preparations and Eudragit S coated tablets for solid preparations were

used in this study.

Takashi Ishibashi et al., 36

evaluated colonic absorbability of drugs dog using a novel

colon-targeted delivery capsule (CTDC). A series of dog studies were performed to

examine the in- vitro/in-vivo relationship of drug release behaviour of the newly

developed CTDC.

Jonathan CDS et al., 37

investigated the coating-dependent release mechanism of a

pulsatile capsule using Nuclear Resonance microscopy. Chrononopharmaceutical

capsules, ethycellulose-coated to prevent water ingress, exhibited clearly different

characteristic when coated by organic or aqueous processes.

Mastiholimath et al., 38

attempted was made to the small intestine (7.0–7.8). So, by

using the deliver theophylline into colon by taking the advantage of the fact that colon

has a lower pH value (6.8) than mixture of the polymers, i.e. Eudragit L and Eudragit S in

proper proportion, pH dependent release in the colon was obtained.

Abraham S et al., 39

reported modified pulsincap dosage form of metronidazle to target

drug release in colon by using extrusion-spheronization method.

Srisagul Sungthongjeen S et al., 40

reported development of pulsatile release tablets with

swelling and rupturable layers. Finally concluded that pulsatile release tablets with a



swelling layer and rupturable ethyl cellulose coating were developed. The system

released the drug rapidly after a certain lag time due to the rupture of ethyl cellulose film.

Krishnaiah YSR et al., 41

developed colon targeted drug delivery systems for

mebendazole the tablets were evaluated for drug content uniformity, and were subjected

to in vitro drug release studies. Differential scanning calorimetry (DSC).

Satyanarayana S et al., 42

presented the delivery of drugs to the colon for local effects,

including drug candidates, methods used for studying colonic drug absorption and colon-

specific drug delivery systems, role of absorption enhancers in colonic drug delivery, and

the use of prodrugs, drugs coated with pH dependent or pH independent biodegradable

polymers, or polysaccharide matrices

Ram Prasad YV et al., 43

assessed the utility of guar gum as a carrier for colon specific

drug delivery using indomethacin as model drug from an oral matrix tablet formulation

containing 40 mg of drug and 340 mg of guar gum.

Krishnaiah YSR et al., 44

used guar gum as a carrier for colon specific and studied

influence of metronidazole and tinidazole on in-vitro release of albendazole from guar

gum matrix tablet and it was found that the release of drug from guar gum formulations

increased with a decrease in the dose of metronidazole / tinidazole.

Leopold CS et al., 45

carried out in-vitro study for the assessment of poly (Laspartic acid)

as a drug carrier for colon specific drug delivery, using dexamethasone as model drug. It

was concluded that poly (L-aspartic acid) appears to be a suitable drug carrier for colon

specific drug delivery.



Rubinstein et al., 46

showed that calcium pectinate-indomethacin tablets of both types,

i.e. compression coated and matrix tablets give no release of indomethacin at a pH-1.5 for

2 hrs.



3.1 DRUG PROFILE25,48,49

3.1.1 FLURBIPROFEN

Chemical Structure:

Molecular Formula: C15H13FO

Average Molecular Weight: 244.2609

Drug Category: Analgesics, Anti-Inflammatory Agents, Non-Steroidal Anti-

inflammatory Agents, Carbonic Anhydrase Inhibitors, Cyclooxygenase Inhibitors

Chemical Name: 2-(3-fluoro-4-phenylphenyl) propanoic acid

Description: Solid. (Solid crystalline powder.)

Odour: Practically odourless

Taste: Not available

Molecular Weight: 244.27 g/mole

Color: White to yellowish.

Melting Point: 110°C (230°F)



Solubility:

Partially soluble in methanol, Very slightly soluble in cold water. Insoluble in diethyl

ether.

Stability: The product is stable.

Storage: Keep container tightly closed. Keep container in a cool, well-ventilated area.

Pharmacokinetics:

Flurbiprofen having a short half life (4 ± 1hours), pKa value 4.2 makes it an ideal

candidate for the design of sustained release pulsatile drug delivery system.

Flurbiprofen [1,1 – biphenyl] – 4-acetic acid, 2-fluro-alpha-methyl, is a important

analgesic and non-steroidal anti-inflammatory drug (NSAID) also with anti-pyretic

properties whose mechanism of action is the inhibition of prostaglandin synthesis. It is

used in the therapy of rheumatoid disorders. Flurbiprofen is rapidly eliminated from the

blood, its plasma elimination half-life is 3-6 hours and in order to maintain therapeutic

plasma levels. The drug must be administered approximately 150-200mg daily by oral

individual dosage. So with the proposed device a new lease of life to an existing drug

molecule can be achieved.

Chronotherapeutic drug delivery release profiles for Flurbiprofen was found to

have generated pro-found interest for the treatment of several diseases including

rheumatoid arthritis, hypertension, bronchial asthma, myocardial infarction, Angina

pectoris, rheumatic disease and ulcer.



3.2 POLYMER PROFILE

3.2.1 EUDRAGIT L 100 AND EUDRAGIT S10050

Chemical structure:

Synonyms : Methacrylic acid, Eudragit.

Functional category : Film former, tablet binder.

Chemical name: Copolymers synthesized from dimethylaminoethyl methacrylate and

other neutral methacrylic esters.

Eudrgit® L 100 and S 100 are anionic copolymers based on methacrylic acid and

methyl methacrylate. The ratio of the free carboxyl groups to the ester groups is approx.

1:1 in eudragit® L 100 and approx. 1:2 in eudrgit® S 100.The average molecular weight

is approx. 135,000.

Description: White powders with a faint characteristic odour.

Solubility: 1 g of eudragit® L 100 or eudragit® S 100 dissolves in 7 g methanol, ethanol,

in aqueous isopropyl alcohol and acetone (containing approx. 3 % water), as well as in 1

N sodium hydroxide to give clear to slightly cloudy solutions. EUDRAGIT® L 100 and

S 100 are practically insoluble in ethyl acetate, methylene chloride, petroleum ether and

water.



Stability and storage condition:

Eudragit S 100 and L 100 polymers are stable at room temperature.

Safety: Acute toxicity studies have been performed in rats, rabbits and dogs. No toxic

effects were observed. Chronictoxicity studies were performed in rats over a period of 3

months. No significant changes were found in the animal organs.

Applications in Pharmaceutical Formulation or Technology:

Eudragit L 100 and S 100 are employed as film coating agents resistant to gastric fluid

with solubility above pH 6.0 and 7.0 respectively, for enteric coating of formulations.

3.2.2 Hydroxypropyl methylcellulose 52,53

Chemical structure:

Non-proprietary names: Hypomellus, hydroxyl propyl methylcellulose 2208, 2906,

2910.

Synonyms: Methyl hydroxypropylcellulose, Propylene glycol ether of methylcellulose,

methylcellulose propylene glycol ether.

Chemical Name & CAS Registry number:

Cellulose, 2-hydroxypropylmethyl-ether Cellulose Hydroxypropylmethylether .

Empirical formula: C8H15 – (C10H18O6) n – C8 H15 O5

Molecular weight: Approximately 86,000



Description: An odourless, tasteless, whit or creamy coloured fibrous or granular

powder.

Functional category: Coating agent, film former, tablet binder, stabilizing agent,

suspending agent, viscosity agent and emulsion stabilizer.

Apparent Density: 0.25 – 0.75 g/cm3

Solubility: Soluble in cold water forming viscous colloidal solution, insoluble in

chloroform, alcohol and ether, but soluble in mixture of methanol and methylene

chloride.

Viscosity: HPMC K4M: 4,000 cps

Stability and Storage Condition: Very stable in dry conditions, Solutions are stable at

pH 3.0 – 11.0. Store in a tight container, in a cool place.

Incompatibility: Extreme pH conditions, oxidizing materials.

Safety: Human and animal feeding studies have shown Hydroxypropyl methylcellulose

to be safe.

CHAPTER 4 CHAPTER 4 CHAPTER 4 CHAPTER 4 MATERIALS AND METHODSMATERIALS AND METHODSMATERIALS AND METHODSMATERIALS AND METHODS

Department of Pharmaceutics, Bharathi College of PharmacyDepartment of Pharmaceutics, Bharathi College of PharmacyDepartment of Pharmaceutics, Bharathi College of PharmacyDepartment of Pharmaceutics, Bharathi College of Pharmacy 31313131

4.1 MATERIALS

The following materials/chemicals were used in the works which are as follows:

Table 4.1: Materials / Chemicals used and source

Sl. No. Materials/ Chemicals Name Of Supplier

1. Flurbiprofen Micro Lab. Bangalore

2. Eudragit L-100 Micro Lab. Bangalore

3. Eudragit S-100 Micro Lab. Bangalore

4. HPMC (K4M Micro Lab. Bangalore

5. Span-80 Micro Lab. Bangalore

6. Acetone Merck Pvt. Ltd.

7. Liquid paraffin(heavy) Merck Pvt. Ltd.

8. Petroleum ether 60-80 C Merck Pvt. Ltd.

9. Potassium di-hydrogen phosphate Merck Pvt. Ltd.

10. Sodium hydroxide Merck Pvt. Ltd.

11. Potassium Chloride Merck Pvt. Ltd.

12. Hydrochloric acid Merck Pvt. Ltd.

4. MATERIALS AND METHODS



EQUIPMENTS

The equipments used in the present work are as follows:

Table 4.2: Equipments used and source

Sl. No. Instruments Source

1. Electronic balance Shimadzu Corporation- Japan

2. UV/Visible spectrophotometer Shimadzu 1700, Shimadzu Corporation.

Japan

3. Scanning electron microscopy JEOL–6360A, Japan.

4. FTIR spectrophotometer Shimadzu, Shimadzu Corporation. Japan

5. Magnetic stirrer Remi Motor Equipments, Mumbai

6. Electrolab dissolution apparatus

(USPXXIII)

Electro lab.

7. Oven Shital Scientific Industries, Mumbai

8. pH meter Elico II-122

9. Distillation unit Biotech India, Mumbai



4.2 METHODS

4.2.1 Preformulation studies

• Preparation of Calibration Curve in 1.2 pH buffer

An accurately weighted amount of Flurbiprofen equivalent to 100 mg was dissolved

in small volume of ethanol, in 100 ml volumetric flask and the volume was adjusted to

100 ml with 1.2 pH buffer and further dilution were made with 1.2 pH buffer. A series of

standard solution containing Beer’s Lambert’s range of concentration from 2 to 16 µg/ml

of Flurbiprofen were prepared and absorbance was measured at 247 nm against reagent

blank. All spectral absorbance measurement was on Shimadzu 1700 UV-visible

spectrophotometer.

• Preparation of Calibration Curve in 6.8 pH phosphate buffer



100 ml with 6.8 pH phosphate buffer and further dilution were made with 6.8 pH

phosphate buffer. A series of standard solution containing Beer’s Lambert’s range of

concentration from 2 to 16 µg/ml of Flurbiprofen were prepared and absorbance was

measured at 247 nm against reagent blank. All spectral absorbance measurement was on

Shimadzu 1700 UV-visible spectrophotometer.

• Preparation of Calibration Curve in 7.4 pH phosphate buffer



100 ml with 7.4 pH phosphate buffer and further dilution were made with 7.4 pH

phosphate buffer. A series of standard solution containing Beer’s Lambert’s range of

concentration from 2 to 16 µg/ml of Flurbiprofen were prepared and absorbance was



measured at 247 nm against reagent blank. All spectral absorbance measurement was on

Shimadzu 1700 UV-visible spectrophotometer.

• Drug-polymer Interaction

FT-IR spectra of the Flurbiprofen, FM3 formulation, Eudragit L-100, Eudragit S-100

were determined by using KBr pellet technique. Samples were scanned over the 500-

4000cm-1

Spectral region at a resolution of 4cm-1

. The ratio of the sample in KBr disc

was 1% (shimadzu FT-IR spectrometer). To ensure no interaction has been occurred

between the drug and polymers.

4.2.2 Preparation of Flurbiprofen microspheres

• Rationale for selection of ingredients and process: 39,40

From literature review, it was evident that the pH in the proximal colon ranges from

6.6 to 7.0. So the Eudragit L-100 and S-100 were combined in different ratios and

solubility of these combinations was found that Eudragit L- 100 and S-100 in the ratio

1:2 was soluble in pH range of 6.6 to 7.0. Hence this combination was selected for

preparation of microspheres. Pure acetone did not dissolve Eudragit; however acetone

with 2% water fitted the criterion well. Liquid paraffin was used was used as the

dispersion media or external phase. Petroleum ether was used to clean the microparticles

since it removes liquid paraffin without the integrity of the microparticles. Solvent

evaporation O/O (oil in oil) emulsification method was chosen since it yields more

uniform particles.



Table 4.3: Formulation design of Flurbiprofen Microspheres using Eudragit L-100 and

Eudragit S-100

• Preparation of Flurbiprofen microsphere: Emulsification-solvent evaporation.

58, 59

Accurately weighted amount of Drug, Eudragit L-100 and S-100 as shown in Table-6

were dissolved in 50ml of acetone to form a homogenous polymers solution. Flurbiprofen

was dispersed in it and mixed thoroughly. This organic phase was slowly poured at 150C

into liquid paraffin (100 ml) containing 1% (w/w) of Span-80 with stirring at 1000 rpm to

form a uniform emulsion. Thereafter, it was allowed to attain room temperature and

stirring was continued until residual acetone evaporated and smooth-walled, rigid and

discrete microspheres were formed. The microspheres were collected by decantation and

the product was washed with petroleum ether (40–600C) and dried at room temperature

for 3 hrs. The microspheres were then stored in a desiccators over fused calcium chloride.

Sl.

No.

Ingredients

Formulation Code

F1 F2 F3 F4

1. Drug (mg) 1000 1000 1000 1000

2 Eudragit L-100 (mg) 166 333 500 666

3. Eudragit S-100 (mg) 332 666 1000 1332

4. Span-80 (ml) 0.5 0.5 0.5 0.5

5. Acetone (ml) 50 50 50 50



4.2.3 Evaluation of Flurbiprofen Microspheres

Prepared microspheres of Flurbiprofen were evaluated for the following parameters:

• Particle size 60

Determination of average particle size of Flurbiprofen microspheres was carried out

by using optical microscopy. A minute quantity of microspheres was spread on a clean

glass slide and average size of 600 microspheres was determined in each batch.

• Study of flow properties of microspheres61

Angle of repose (θ) of the microspheres, which measures the resistance to particle

flow, was determined by a fixed funnel method. The height of the funnel was adjusted in

such a way that the tip of the funnel just touches the heap of the blends. Accurately

weighed microspheres were allowed to pass through the funnel freely on to the surface.

The height and diameter of the powder cone was measured and angle of repose was

calculated using the following equation

θ = tan-1

h/r

Where h/r is the surface area of the free standing height of the microspheres heap that is

formed on a graph paper after making the microspheres flow from the glass funnel.

• Percentage yield 62

The measured weight was divided by total amount of all non-volatile components

which were used for the preparation of microsphere.

% yield = Total weight of excipient and drug / Actual weight of product x 100

• Drug Content Uniformity 63

In 100ml volumetric flask 25mg of crushed microspheres were taken and dissolved

with small quantity of ethanol and the volume was made up to mark with pH 6.8 and



stirred for 12 hrs. After stirring the solution was filtered through whatman filter paper and

from the filtrate appropriate dilutions were made and absorbance was measured at 247

nm by using UVspectrophotometer.

• Scanning Electron Microscopy 64

It has been used to determine particle size distribution, surface topography, texture

and examine the morphology of fractured or sectioned surface. The samples for SEM

analysis were prepared by following method. Dry microspheres brass stub a coated with

gold in an ion sputter. Then picture of microspheres were taken by random scanning of

the stub. The SEM analysis or the microspheres was carried out by using JEOL–6360A

analytical scanning electron microscope. The microspheres were viewed at an

accelerating voltage of 20KV.

• In-vitro dissolution study 38,58

In vitro dissolution profile of each formulation was determined by employing USP

XXIII rotating basket method (900 ml of pH 6.8-phosphate buffer, 100 rpm and

37±0.50C). Microspheres equivalent to 150 mg of Flurbiprofen was loaded into the basket

of the dissolution apparatus. Dissolution study carried out for 12 hrs. 5 ml of the sample

was withdrawn from the dissolution media at suitable time intervals and the same amount

was replaced with fresh buffer. The absorbance was measured at 247 nm by using

Shimadzu 1700 UV spectrophotometer, against pH 6.8 as blank.

4.2.4 Preparation of Cross-Linked Gelatin Capsules 38, 39

• Formaldehyde treatment

Formalin treatment has been employed to modify the solubility of gelatin capsules.

Exposure to formalin vapours results in an unpredictable decreases in solubility of gelatin



owing to the cross linkage of the amino group in the gelatin molecular chain aldehyde

group of formaldehyde by Schiff’s base condensation.

Procedure

Hard gelatin capsule of size 00 and 000 in number taken. Their bodies were

separated from the caps. 25 ml of 15% (v/v) formaldehyde was taken into desiccators and

a pinch of potassium permanganate was added to it, to generate formalin vapours. The

wire mesh containing the empty bodies of capsule was then exposed to formaldehyde

vapours. The caps were not exposed leaving them water-soluble. The desiccators were

tightly closed. The reaction was carried out for 12 h after which the bodies were removed

and dried at 500C for 30 min to ensure completion of reaction between gelatin and

formaldehyde vapours. The bodies were then dried at room temperature to facilitate

removal of residual formaldehyde.

These capsule bodies were capped with untreated caps and stored in a polythene bag.

• Tests for Formaldehyde Treated Empty Capsules

Various physical and chemical test were carried out simultaneously for

formaldehyde treated and untreated capsules.

4.2.5 Physical tests

• Identification attributes

The ‘00’ capsule were one with a red cap and red colored body. They were lockable

type, odorless, softy and sticky when treated with wet fingers. After formaldehyde

treatment, there were no significant changes in the capsules. They were non-tacky when

touched with wet fingers.



• Visual defect

In about 100 capsule bodies treated with formaldehyde, about ten were found to be

shrunk or distorted.

• Dimensions

Variations in dimensions between formaldehyde, treated and untreated capsules were

studied. The length and diameter of the capsules were measured before and after

formaldehyde treatment, using dial caliper.

• Solubility studies of treated capsules

The solubility test was carried out for normal capsules and formaldehyde treated

capsules for 24 hrs. Ten capsules were randomly selected and then subjected to solubility

studies at room temperatures in buffers of pH 1.2, 7.4 and 6.8. 100 ml solution and stirred

for 24 hrs. The time at which the capsule dissolves or forms a soft fluffy mass was noted.

4.2.6 Chemical test

• Qualitative test for free formaldehyde51

Standard formaldehyde solution used is formaldehyde solution (0.002, w/v) and

sample solution is formaldehyde treated bodies (about 25 in number) were cut into small

pieces and taken into a beaker containing distilled water. This was stirred for 1 hr with a

magnetic stirrer, to solubilize the free formaldehyde. The solution was then filtered into a

50 ml volumetric flask, washed with distilled water and volume was made up to 50 ml

with the washings.

Procedure

1ml of sample solution, 9ml of water was added. One millilitre of resulting

solution was taken into a test tube and mixed with 4ml of water and 5ml of acetone



reagent. The test tube was warmed in a water bath at 400C and allowed to stand for 40

min. The solution was not more intensely colored than a reference solution prepared at

the same time and in the same manner using 1ml of standard solution in place of the

sample solution. The comparison should be made by examining tubes down their vertical

axis.

4.3 FORMULATION OF PULSATILE (MODIFIED PULSINCAP) DRUG

DELIVERY SYSTEM: 18,38,39,65

Microspheres equivalent to 150mg of Flurbiprofen were accurately weighed and

filled into the previously formaldehyde treated bodies by hand filling. The bodies

containing the microspheres were then plugged with different amounts of polymers

hydroxylpropylmethylcellulose. Then join the capsule body and cap and sealed with a

small amount of the 5% ethyl cellulose ethanolic solution. The sealed capsules were

completely coated with 5% Cellulose Acetate Phthalate (CAP) to prevent variable gastric

emptying. The whole system thus produced is modified pulsincap. Overview of designed

pulsatile device was shown in Fig 4.1.

4.3.1 Coating of pulsincap

5 % w/w solution of CAP was prepared by using acetone: ethanol (8.2) as a

solvent and dibutyl phthalate as plasticizer (0.75%) as a plasticizer. Dip coating method

was followed to develop the pulsincap. The capsules were alternatively dipped in 5 %

CAP solution and dried. Coating was repeated until an expected weight gain of.8-12%

was obtained and the capsule resists disintegration in 0.1 N HCL for a minimum period

of 2 hrs.



Figure 4.1: Overview of designed pulsatile device

4.3.2 Evaluation of Modified Pulsincap 39,40

• Drug Polymer Interaction

FT-IR spectra of physical mixture of Flurbiprofen and HPMC were carried out by

using KBr pellet technique. Samples were scanned over the 500-4000cm-1

Spectral region

at a resolution of 4cm-1

. The ratio of the sample in KBr disc was 1% (shimadzu FTIR

spectrometer).

• Thickness of cellulose acetate phthalate coating

The thickness of cellulose acetate phthalate coating was measured using screw gauge

and expressed in mm.

• Weight variation

10 capsules were selected randomly from each batch and weight individually for

weight variation.

• In vitro release profile

Dissolution studies were carried out by using USP XXIII dissolution test apparatus

(Basket) method. Capsules were placed in a basket so that the capsule should be

immersed completely in dissolution media but not float. In order to simulate the pH



changes along the GI tract, three dissolution media with pH 1.2, 7.4 and 6.8 were

sequentially used referred to as sequential pH change method. When performing

experiments, the pH 1.2 medium was first used for 2 hrs (since the average gastric

emptying time is 2 hrs) then removed and the fresh pH 7.4 phosphate buffer saline (PBS)

was added. After 3 hrs (average small intestinal transit time is 3 hrs) the medium was

removed and fresh pH 6.8 dissolution medium was added for subsequent hrs. 900ml of

the dissolution medium was used at each time. Rotation speed was 100 rpm and

temperature was maintained at 37±0.50C. 5ml of dissolution media was withdrawn at

predetermined time intervals and fresh dissolution media was replaced. The withdrawn

samples were analyzed at 247 nm, by UV absorption spectroscopy.

• Kinetics of drug release

To examine the drug release kinetics and mechanism, the cumulative release data were

fitted to models representing zero order (Q v/s t), first order [Log(Q0-Q) v/s t], Higuchi’s

square root of time (Q v/s t1/2

) and Korsemeyer Peppas double log plot (log Q v/s log t)

respectively, where Q is the cumulative percentage of drug released at time t and (Q0-Q) is the

cumulative percentage of drug remaining after time t. In short, the results obtained from in

vitro release studies were plotted in four kinetics models of data treatment as follows:

� Cumulative percentage drug release Vs. Time (zero order rate kinetics)

� Log cumulative percentage drug retained Vs. Time (first order rate kinetics)

� Cumulative percentage drug release Vs. √T (Higuchi’s classical diffusion equation)

� Log of cumulative percentage drug release Vs. log Time (Peppas exponential

equation)

CHAPTER 5 CHAPTER 5 CHAPTER 5 CHAPTER 5 RESULRESULRESULRESULTS TS TS TS



Table 5.1: Standard calibration data of Flurbiprofen in pH 1.2, 6.8 and 7.4 buffers at

247 nm

SI.NO. Concentration

(mcg/ml)

Absorbance (247 nm)

1.2 6.8 7.4

1 0.000 0.000 0.000 0.000

2 2.000 0.085 0.078 0.115

3 4.000 0.165 0.152 0.23

4 6.000 0.242 0.228 0.345

5 8.000 0.335 0.308 0.455

6 10.000 0.419 0.386 0.576

7 12.000 0.505 0.454 0.688

8 14.000 0.583 0.538 0.803

9 16.00 0.654 0.612 0.917

• Standard calibration curve of Flurbiprofen in pH 1.2 buffer at 247 nm

Figure 5.1: Standard calibration curve of Flurbiprofen in pH 1.2 buffer at 247 nm

5. RESULTS



• Standard calibration curve of Flurbiprofen in pH 6.8 phosphate buffer at

247 nm

Figure 5.2: Standard calibration curve of Flurbiprofen in pH 6.8 buffer

• Standard calibration curve of Flurbiprofen in pH 7.4 phosphate buffer at

247 nm

Figure 5.3: Standard calibration curve of Flurbiprofen in pH 7.4 buffer



• Infrared spectroscopy

The FT-IR spectra study showed no change in the finger print of pure drug

spectra, thus confirming absence of drug and polymer interaction.

Figure 5.4: I.R. Spectrum of Flurbiprofen (pure drug)

Figure 5.5: I.R. Spectrum of physical mixture of drug and polymer combinations




F1 F2

F3 F4 Figure 5.6: Image showing microspheres of Flurbiprofen formulations


• Micromeritic properties

Table 5.2: Micromeritic properties of Flurbiprofen Microspheres

Formulation code Mean particles size±±±±S.D (µµµµm) Angle of repose±±±±S.D

F1 164.62 ± 1.04 18° 75” ± 2.89

F2 168.12 ± 1.21 18° 62” ± 1.79

F3 195.99± 2.69 22° 09” ± 2.61

F4 249.92 ± 1.91 23° 36” ± 2.99

All values are represented as mean ± standard deviation (n=3)



• Percentage yield and drug content

Table 5.3: Percentage yield and Drug content of Flurbiprofen microspheres

Formulation code Percentage yield±±±±S.D Drug content uniformity±±±±S.D

F1 89.61 ± 0.40 82.79% ± 0.68

F2 86.56 ± 0.27 88.23% ± 0.95

F3 91. 54 ± 0.18 96.19% ± 0.28

F4 88.85 ± 0.22 85.09% ± 0.16


• Scanning Electron Microscopy (SEM)

Figure 5.7: Scanning electron microphotographs of F3 formulation.



• Evaluation of In-vitro drug release of Flurbiprofen microspheres

Table 5.4: In-vitro release data of Flurbiprofen microspheres (F1)

Time

(T)

Hrs

Square

root of

Time

Log

Time

Cum.%

Drug

release ± SD

Cum.%

Drug

retained

Log Cum.

% drug

released

Log Cum.

% Drug

retained

0 0.00 0.000 0.000 0.000 0.000 0.000

0.5 0.70 -0.301 28.39 ± 1.06 71.61 1.453 1.854

1 1.00 0.000 34.06 ± 1.21 65.94 1.532 1.819

2 1.41 0.301 40.98 ± 1.30 59.02 1.612 1.770

3 1.73 0.477 47.66 ± 0.76 52.34 1.678 1.718

4 2.00 0.602 57.51 ± 1.10 42.49 1.759 1.628

5 2.23 0.698 61.02 ± 1.16 38.98 1.785 1.590

6 2.44 0.778 64.29 ± 1.04 35.71 1.808 1.552

7 2.64 0.845 68.72 ± 1.21 31.28 1.837 1.495

8 2.82 0.903 75.73 ± 0.92 24.27 1.879 1.385

9 3.00 0.954 79.8 ± 1.13 20.2 1.902 1.305

10 3.16 1.000 85.11 ± 0.98 14.89 1.929 1.172

11 3.31 1.041 91.01 ± 1.01 8.99 1.959 0.953

12 3.46 1.079 95.91 ± 0.94 4.09 1.981 0.611





Time

(T)

Hrs

Square

root of

Time

Log

Time

Cum.% Drug

release ± SD

Cum.%

Drug

retained

Log Cum.

% drug

released

Log Cum.

% Drug

retained

0 0.00 0.000 0.000 0.000 0.000 0.000

0.5 0.70 -0.301 26.23 ± 1.08 73.77 1.418 1.867

1 1.00 0.000 36.08 ± 1.25 63.92 1.557 1.805

2 1.41 0.301 41.28 ± 1.10 58.72 1.615 1.768

3 1.73 0.477 45.03 ± 1.26 54.97 1.653 1.740

4 2.00 0.602 47.92 ± 1.08 52.08 1.680 1.716

5 2.23 0.698 55.11 ± 0.91 44.89 1.741 1.652

6 2.44 0.778 62.99 ± 1.95 37.01 1.799 1.568

7 2.64 0.845 68.09 ± 2.06 31.91 1.833 1.503

8 2.82 0.903 75.15 ± 1.84 24.85 1.875 1.395

9 3.00 0.954 84.79 ± 0.96 15.21 1.928 1.182

10 3.16 1.000 88.95 ± 1.27 11.05 1.949 1.043

11 3.31 1.041 90.76 ± 1.65 9.24 1.957 0.965

12 3.46 1.079 92.06 ±1.61 7.94 1.964 0.899





Time

(T)

Hrs

Square

root of

Time

Log

Time

Cum.%

Drug

release ± SD

Cum.%

Drug

retained

Log Cum.

% drug

released

Log Cum.

% Drug

retained

0 0.00 0.000 0.000 0.000 0.000 0.000

0.5 0.70 -0.301 26.36 ± 0.25 73.64 1.420 1.867

1 1.00 0.000 31.17 ± 1.06 68.83 1.493 1.837

2 1.41 0.301 34.77 ± 1.11 65.23 1.541 1.814

3 1.73 0.477 41.21 ± 0.83 58.79 1.615 1.769

4 2.00 0.602 46.78 ± 0.91 53.22 1.670 1.726

5 2.23 0.698 54.06 ± 0.67 45.94 1.732 1.662

6 2.44 0.778 59.90 ± 0.85 40.1 1.777 1.603

7 2.64 0.845 62.92 ± 0.46 37.08 1.798 1.569

8 2.82 0.903 65.97 ± 0.76 34.03 1.819 1.531

9 3.00 0.954 72.09 ± 1.26 27.92 1.857 1.445

10 3.16 1.000 79.90 ± 1.42 20.1 1.902 1.303

11 3.31 1.041 82.96 ± 0.59 17.04 1.918 1.231

12 3.46 1.079 89.17 ± 1.28 10.83 1.950 1.034





Time

(T)

Hrs

Square

root of

Time

Log

Time

Cum.%

Drug

release ± SD

Cum.%

Drug

retained

Log Cum.

% drug

released

Log Cum.

% Drug

retained

0 0.00 0.000 0.000 0.000 0.000 0.000

0.5 0.70 -0.301 24.10 ± 0.46 75.9 1.382 1.880

1 1.00 0.000 31.27 ± 0.39 68.73 1.495 1.837

2 1.41 0.301 37.06 ± 0.39 62.94 1.568 1.798

3 1.73 0.477 41.55 ± 0.19 58.45 1.618 1.766

4 2.00 0.602 47.39 ± 0.84 52.61 1.675 1.721

5 2.23 0.698 52.21 ± 0.47 47.79 1.717 1.679

6 2.44 0.778 59.44 ± 0.47 40.56 1.774 1.608

7 2.64 0.845 66.04 ± 0.24 33.96 1.819 1.530

8 2.82 0.903 71.92 ± 0.35 28.08 1.856 1.448

9 3.00 0.954 78.05 ± 0.37 21.95 1.892 1.341

10 3.16 1.000 80.78 ± 0.49 19.22 1.907 1.283

11 3.31 1.041 83.99 ± 0.01 16.01 1.924 1.204

12 3.46 1.079 87.81 ± 1.53 12.19 1.943 1.086




Figure 5.8: Cumulative % release of Flurbiprofen microspheres

Table 5.8: Kinetic values obtained from in-vitro release profile for Flurbiprofen

microspheres

Formu

lation

Code

Zero order

kinetic

data(r2)

First order

kinetic

data(r2)

Higuchi

Matrix

kinetic

data(r2)

Peppas kinetic data

( r2

and n value)

F1 0.9190 0.07896 0.9884 0.973 0.2115

F2 0.9290 0.06747 0.9758 0.943 0.2236

F3 0.9359 0.01035 0.9814 0.959 0.2212

F4 0.9366 0.01492 0.9874 0.962 0.2457



0 5 10 15 20 25 300

20

40

60

80

100

120

F1

F2

F3

F4

Time(hrs)

cum

% d

rug

rel

ease

Figure 5.9: Zero order plots of Flurbiprofen microspheres

0 5 10 15 20 25 300.0

0.5

1.0

1.5

2.0

F1

F2

F3

F4

Time(hrs)

Lo

g %

cu

m d

rug

reta

ined

Figure 5.10: First order plots of Flurbiprofen microspheres



1 2 3 4 5 6

-40

-20

0

20

40

60

80

100

120

F1

F2

F3

F4

Square root of time

cum

% d

rug

rel

ease

Figure 5.11: Higuchi diffusion plots of Flurbiprofen microspheres

-0.5 0.0 0.5 1.0 1.5

0.5

1.0

1.5

2.0

2.5

F1

F2

F3

F4

Log T

Lo

g %

cu

m d

ru

g r

ele

ase

Figure 5.12: Peppas exponentional plots of Flurbiprofen microspheres



5.1.4 Preparation of Cross-Linked Gelatin Capsules

These capsule bodies were capped with untreated caps and stored in a polythene bag

5.1.5 Physical test

• Dimension

Average capsule length

� Before formaldehyde treatment (untreated cap and body) : 23.5 mm

� After formaldehyde treatment (treated body and untreated cap) : 22.6 mm

Average diameter of capsule body

� Before formaldehyde treatment : 7.9 mm

� After formaldehyde treatment : 7.5 mm

Average length of capsule body

� Before formaldehyde treatment : 20.6 mm

� After formaldehyde treatment : 19.5 mm

• Solubility studies for the treated capsules

When the capsules were subjected to solubility studies in different buffers

for 24 hrs, the following observation were made

a) In all the case of normal capsules, both cap and body dissolved within fifteen

minutes.

b) In the case of formaldehyde treated capsules, only the cap dissolved within

15minutes, while the capsule remained intact for about 24 hours.

5.1.6 Quantity test for free formaldehyde

The formaldehyde capsules were tested for the presence of free formaldehyde.

The sample solution was not more intensely colored than the standard solution

inferring that less than 20µg free formaldehyde is present in 25 capsule




DELIVERY SYSTEM


Table 5.9: Composition for modified pulsatile device on the basis of design summary

Formul.

No.

Wt.of empty

Body(mg)

Wt.of micro

sphere(mg)

Wt.of

polymer

used(mg)

Total weight

With cap (mg)

Wt. after

CAP

coating (mg)

F5 67.5 355 20 442.5 451.34

F6 67.4 355 30 452.4 460.08

F7 68.5 355 40 463.5 473.25

HPMC: Hydroxy Propyl Methylcellulose.

5.2.2 Evaluation of modified pulsincap

• IR- Study

From the spectra of pure drug and the combination of drug with polymers, it

was observed that all the characteristics peaks of Flurbiprofen were present in the

combination spectrum, thus indicating compatibility of the drug and polymer.

Figure 5.13: I.R. Spectrum of physical mixture of Flurbiprofen and HPMC



• Thickness of Cellulose Acetate Phthalate

Table 5.10: Coating thickness

Formulation Thickness of Coating (mm*)

F5 0.065

F6 0.053

F7 0.060

*Average of triplicate sets

• Weight variation

The filled capsules pass the weight variation test as their weights are within the

specified limits.

Table 5.11: Weight variation

Formulation Weight variation (mg*)

F5 447.97

F6 456.21

F7 477.27

*Average of triplicate sets



• In vitro release profile

Table 5.12: In-vitro release data of F5 containing 20mg HPMC

Time

(T)

Hrs

Square

root of

Time

Log

Time

Cum.%

Drug release

± SD

Cum.%

Drug

retained

Log

Cum. %

drug

released

Log

Cum. %

Drug

retained

0 0.00 0.000 0.000 0.000 0.000 0.000

1 1.00 0.000 0.000 100 0.000 2.000

2 1.41 0.301 0.000 100 0.000 2.000

3 1.73 0.477 0.000 100 0.000 2.000

4 2.00 0.602 2.39 ± 0.25 97.61 0.378 1.989

5 2.23 0.698 5.70 ± 0.09 94.3 0.755 1.974

6 2.44 0.778 27.54 ± 0.53 72.46 1.439 1.860

7 2.64 0.845 32.51 ± 0.32 67.49 1.512 1.829

8 2.82 0.903 39.02 ± 0.78 60.98 1.591 1.785

9 3.00 0.954 43.09 ± 046 56.91 1.634 1.634

10 3.16 1.000 47.11 ± 0.16 52.89 1.673 1.723

11 3.31 1.041 55.17 ± 0.29 44.83 1.741 1.651

12 3.46 1.079 64.30 ± 0.30 35.7 1.808 1.552

13 3.60 1.113 66.50 ± 0.51 33.5 1.822 1.525

14 3.74 1.146 73.04 ± 0.80 26.96 1.863 1.430

15 3.87 1.176 75.96 ± 0.27 24.04 1.880 1.380





Time

(T)

Hrs

Square

root of

Time

Log

Time

Cum.%

Drug release

± SD

Cum.%

Drug

retained

Log

Cum. %

drug

released

Log

Cum. %

Drug

retained

0 0.00 0.000 0.000 0.000 0.000 0.000

1 1.00 0.000 0.000 100 0.000 2.000

2 1.41 0.301 0.000 100 0.000 2.000

3 1.73 0.477 0.000 100 0.000 2.000

4 2.00 0.602 0.000 100 0.000 2.000

5 2.23 0.698 4.52 ± 0.12 95.48 0.655 1.979

6 2.44 0.778 26.98 ± 0.21 73.02 1.431 1.863

7 2.64 0.845 31.11 ± 0.12 68.89 1.492 1.838

8 2.82 0.903 34.96 ± 0.56 65.04 1.543 1.813

9 3.00 0.954 44.02 ± 0.22 55.98 1.643 1.748

10 3.16 1.000 49.14 ± 0.51 50.86 1.691 1.706

11 3.31 1.041 55.9 ± 0.22 44.1 1.747 1.644

12 3.46 1.079 63.12 ± 0.89 36.88 1.800 1.566

13 3.60 1.113 65.06 ± 0.17 34.94 1.813 1.543

14 3.74 1.146 68.58 ± 0.05 31.42 1.836 1.497

15 3.87 1.176 72.01 ± 0.25 27.99 1.857 1.447





Time

(T)

Hrs

Square

root of

Time

Log

Time

Cum.% Drug

release ± SD

Cum.%

Drug

retained

Log

Cum.

% drug

released

Log

Cum.

% Drug

retained

0 0.00 0.000 0.000 0.000 0.000 2.000

1 1.00 0.000 0.000 100 0.000 2.000

2 1.41 0.301 0.000 100 0.000 2.000

3 1.73 0.477 0.000 100 0.000 2.000

4 2.00 0.602 0.000 100 0.000 2.000

5 2.23 0.698 0.42 ± 0.05 95.48 -0.376 1.979

6 2.44 0.778 5.72± 0.23 94.28 0.757 1.974

7 2.64 0.845 19.02 ± 0.34 80.98 1.279 1.908

8 2.82 0.903 28.98 ± 0.22 71.02 1.462 1.851

9 3.00 0.954 32.99 ± 0.56 67.01 1.518 1.826

10 3.16 1.000 38.07 ± 0.90 61.93 1.580 1.791

11 3.31 1.041 43.55 ± 0.27 56.45 1.638 1.638

12 3.46 1.079 51.25 ± 0.33 48.75 1.709 1.687

13 3.60 1.113 54.03 ± 0.39 45.97 1.732 1.662

14 3.74 1.146 56.87 ± 0.36 43.13 1.754 1.634

15 3.87 1.176 59.92 ± 0.51 40.08 1.777 1.602




Figure 5.14: Cumulative % release of Flurbiprofen microspheres containing HPMC

as hydrogel plug

Table 5.15: Kinetic values obtained from in-vitro release data for Flurbiprofen

microspheres

Formulation

Code

Zero order

kinetic

data(r2)

First order

kinetic

data(r2)

Higuchi

Matrix

kinetic

data(r2)

Peppas kinetic data

(r2

and n value)

F5 0.9589 0.945 0.923 0.880 2.622

F6 0.9503 0.943 0.930 0.821 2.724

F7 0.9306 0.942 0.937 0.926 2.459



0 5 10 15 20 25 300

20

40

60

80

100

120

F5

F6

F7

Time(hrs)

cum

% d

rug

rel

ease

Figure 5.15: Zero order plots of formulation containing HPMC as hydrogel plug

0 5 10 15 20 25 300.0

0.5

1.0

1.5

2.0

2.5

F5

F6

F7

Time(hrs)

Lo

g %

cu

m d

rug

reta

ined

Figure 5.16: First order plots of formulation containing HPMC as hydrogel plug



1 2 3 4 5 6

-40

-20

0

20

40

60

80

100

120

F5

F6

F7

Square root of time

cum

% d

rug

rele

ase

Figure 5.17: Higuchi diffusion plots of formulation containing HPMC as hydrogel

plug

0.5 1.0 1.5

-1

0

1

2

3

F5

F6

F7

Log T

Lo

g %

cu

m d

ru

g r

ele

ase

Figure 5.18: Peppas exponentional plots of formulation containing HPMC as

hydrogel plug

CHAPTER 6 CHAPTER 6 CHAPTER 6 CHAPTER 6 DISCUSSIONDISCUSSIONDISCUSSIONDISCUSSION

Department of PharmaceuticDepartment of PharmaceuticDepartment of PharmaceuticDepartment of Pharmaceutics, Bharathi College of Phs, Bharathi College of Phs, Bharathi College of Phs, Bharathi College of Pharmacy armacy armacy armacy 64646464

In the current research, pulsatile drug delivery system containing eudragit

microspheres with subsequently lower dose of Flurbiprofen for colon specific delivery

was developed and evaluated.


• Standard calibration curve of Flurbiprofen

Standard calibration curve of Flurbiprofen was carried out in 1.2 pH, 6.8 pH and

7.4 pH buffer at 247 nm. The r2

value in the entire medium shows nearly 1, which

signifies linearity. (Fig 5.1 to 5.3 and Table 5.1)

• IR Studies

Drug-polymer interaction study was carried out for pure drug and physical

mixtures of drug and polymers. Flurbiprofen was used in this study which contains

carboxylic acid function responsible for a broad hump 3200 cm-1

.The aromatic C-H

peaks was observed at 3076, 3063, 3032 cm-1

. The broad carboxylic acid absorption is

noticed at 1701 cm-1

. These data are in concurrent with the structure of the drug

molecular. (Fig 5.4). The physical mixture showed identical spectrum with respect to the

spectrum of the pure drug, indicating there is no chemical interaction between the drug

molecule and polymers. (Fig 5.5)


Microspheres of Flurbiprofen were prepared using Eudragit L-100/S-100 by

emulsion solvent evaporation method as shown in Table 4.3. In this method, the organic

phase was slowly poured in liquid paraffin and the emulsion was stabilized by Span- 80.

6. DISCUSSION



The organic phase evaporated and finally spherical, smooth–walled, rigid and discrete

microspheres were formed. (Fig 5.6)


• Particle size

With increase in polymer concentration, the mean particle size of the

microspheres significantly increased and was range was between 164.62 to 249.92 µm.

The reason for this is, as the polymer concentration increases, viscosity of medium

increase and resulting in enhanced interfacial tension. Shearing efficiency is also

diminished at higher viscosities. This may be resulting in the formation of large particles.

(Table 5.2)

• Flow properties

The value of θ for prepared microspheres was between 18° 75” - 23° 36” which

indicates reasonable flow and all the batches were found to fit with respect of flowability.

(Table 5.2)

• Percentage yield

Percentage yield of the formulation was carried out and was found to be within

the range between 86.56 to 91.54 %. (Table 5.3)

• Drug Content

Drug content of the formulation was carried out and was found to be within the

range between 82.79 to 96.19%. (Table 5.3)

• Scanning Electron Microscopy

Scanning electron microscopy confirms the outer surface of F3 formulation was

smooth and dense, while the internal surface was porous. The shell of microspheres also



showed some porous structure it may be caused by evaporation of solvent entrapped

within the shell of microspheres after forming smooth and dense layer. (Fig 5.7)

• In-vitro release studies

The In-vitro release studies of prepared Flurbiprofen microspheres were carried in

pH 6.8 buffer as a diffusion medium for a period of 12 hrs. As the amount of polymer

concentration increased, drug release from the formulations decreased. The release

showed a biphasic release with an initial burst effect. At the end of first 30 min. drug

release was 28.39%, 26.23%, 26.36% and 24.10% for F1 to F4 respectively. The

mechanism for the burst release can be attributed to the drug loaded on the microcapsule

or imperfect entrapment of drug.

The cumulative % release for F1, F2, F3 and F4 were found to be 95.91%,

92.06%, 89.17%, and 87.81% at the end of 12th

hrs. (Tables 5.4 to 5.7 and Fig 5.8)

The R2 values for zero order kinetics of F1, F2, F3 and F4 were 0.9190, 0.9290,

0.9359and 0.9366 respectively indicate the drug follows zero order release.(Table 5.8 an

Fig 5.9)

The R2 values for First order kinetics of F1, F2, F3 and F4 were 0.07896, 0.06747,

0.01035 and 0.01492respectively indicate the drug follows zero order release (Table 5.8

an Fig 5.10)

To find out the drug release mechanism, the in-vitro data were subjected to

Higuchi diffusion. The Higuchi diffusion plots of all the formulations were linear. Hence

it confirms release follows Higuchi diffusion mechanism. (Table 5.8 and Fig 5.11)



The formulations were subjected to peppas plots, results found fairly linear and

slope value was calculated (n value) which was in ranges of 0.2115 to 0.2457 indicating

the drug was released by Fickian diffusion mechanism. (Table 5.8 and Fig 5.12)

6.1.4 Preparation of Cross-Linked Gelatin Capsules

Formaldehyde treatment of hard gelatin capsules

The bodies of hard gelatine capsules were made insoluble by formaldehyde

treatment. This was done by exposing the bodies of the capsules to vapours of

formaldehyde; the caps were not exposed leaving them water-soluble. The capsules were

tested for physical and chemical changes caused by exposure to vapours of

formaldehyde.

6.1.5 Physical test

• Dimensions

On formaldehyde treatment, the ‘00’ size capsule bodies showed a significant

decrease in length and diameter.

• Solubility studies

When the capsules were subjected to studies in different buffers, the untreated

caps disintegrated within 10 mins in all the media whereas the treated bodies remained

intact for about 24 hrs.

• Quantitative test for free formaldehyde

The sample solution was less intensively coloured when compared with standard

inferring that less than 20 µg/ml of free formaldehyde is present in 25 capsules bodies (as

per the I.P )




DELIVERY SYSTEM


Microspheres equivalent to 150 mg of Flurbiprofen were filled into the treated

bodies and plugged with HPMC at different concentrations. The filled capsules were

completely coated with 5% CAP solution. These pulsatile drug delivery systems were

further evaluated. (Table 5.9)

6.2.2 Evaluation of modified pulsincap

• IR studies

Drug-polymer interaction study was carried out for physical mixture of pure

drug(Flurbiprofen) and HPMC.The results rule out the incompatibility between drug and

polymer ( Fig 5.13)

• Thickness

The thickness of the CAP coating was measured by using screw gauge. The

values ranged from 0.053-0.065 mm. (Table 5.10)

• In-vitro release studies

The dissolution studies, depicits the enteric coat of the cellulose acetate phthalate

was intact for nearly two hours in pH 1.2, but dissolved in intestinal pH, leaving the

soluble cap of capsule, which also dissolved in pH 7.4 phosphate buffer. The exposed

HPMC polymer plug which absorbed the surrounding fluid, star swelling and release the

drug through the swollen matrix. After complete wetting of the plug, it formed a soft

mass, which was then easily ejected out of the capsule body; releasing the eudragit

microspheres into simulated colonic fluid (pH 6.8 phosphate buffer).



In all the formulations, there was absolutely no drug release in pH 1.2, thus

indicating the efficiency of 5% CAP for enteric coating. Very slight release was observed

in pH 7.4 phosphate buffer.

The F5, F6, F7 formulation at the end of 15th

hrs shows the drug release of 75.96

%, 72.01 % and 59.92 % respectively. As the concentration of polymer increases the drug

release decreases. (Tables 5.12 to 5.14 and Fig 5.14)

The r2

value in higuchi plot confirms the drug release by Higuchi diffusion

mechanism. The formulations were subjected to peppas plots by taking log cum % drug

released versus log time. The plots are found fairly linear and the ‘r2’ values are near to 1

and also slope value was calculated (n value) which was in ranges of 2.459 to 2.724,

indicating the drug was released by Super Case II transport diffusion mechanism. (Table

5.15 and Figs 5.15 to 5.18)

CHAPTER 7 CHAPTER 7 CHAPTER 7 CHAPTER 7 CONCLUSIONCONCLUSIONCONCLUSIONCONCLUSION

Department of Pharmaceutics,Department of Pharmaceutics,Department of Pharmaceutics,Department of Pharmaceutics, Bharathi College of Pharmacy. Bharathi College of Pharmacy. Bharathi College of Pharmacy. Bharathi College of Pharmacy. 70707070

The results obtained from the study of “Design and evaluation of

chronotherapeutic drug delivery system of flurbiprofen ” provide the following

conclusion

• The particle size increased significantly as the amount of polymer increased.

• The flow properties of all the prepared microspheres were good as indicated by

low angle of repose (θ < 40º).The good flow properties suggested that the

microspheres produced were non-aggregated.

• As the entrapment efficiency was good in all the cases, suggest that optimized

parameters were used in the method of preparations.

• The In-vitro drug release of microspheres exhibits two type release pattern for all

microspheres with initial burst release effect, which may be attributed to the drug

loaded onto the surface of the particles.

• On the basis of, particle size, drug content, Scanning Electron Microscopy, IR-

study, in-vitro release studies and its kinetic data, F3 was selected as an optimized

formulation for designing pulsatile device.

• The 1:2 ratio of Eudragit L-100 and S-100 are suitable for preparation of

microspheres for colonic targeting.

• The solubility studies of formaldehyde treated empty gelatine capsule bodies,

signifies that they are intact for 24 hrs, and hence suitable for colon targeting.

• Hence, finally it was concluded that the prepared pulsatile drug delivery system

can be considered as one of the promising formulation technique for preparing

colon specific drug delivery systems and hence in chronotherapeutic management

of arthritis.

7. CONCLUSION

CHAPTER 8 CHAPTER 8 CHAPTER 8 CHAPTER 8 SUMMARYSUMMARYSUMMARYSUMMARY


Over the past two decades there has been a growing appreciation on the

importance of circadian rhythms on GIT physiology and on disease states, together with

the realization of the significance of time-of-day of the administration on resultant

pharmacodynamics and pharmacokinetics parameters.

The colon is a site where both local and systemic delivery of drug can take place.

By targeting the drug to the colon the efficacy of the drug will be improved. In the

present study, by keeping the objective of treating rheumatoid arthritis, an attempt was

made to design and prepare chronotherapeutic, colon specific drug delivery system in

order to target the drug to the colon.

Flurbiprofen microspheres were prepared using Eudragit L/S 100 in ratio 1:2 by

emulsion solvent evaporation method. Four formulations (F1 to F4) were prepared by

varying the ratio of the drug and polymer. IR-study reveals there is not significant

interaction between drug and polymers. The prepared formulations were subjected to

various evaluation parameters like particle size, flow properties, percentage yield, drug

content, scanning electron microscopy and in-vitro drug release studies. From the results,

the formulation F3 emerges as the optimum formulation to design time and pH

dependent, pulsatile drug delivery system.

In the next step, the capsule bodies were made insoluble by formaldehyde

treatment and these were subjected to various physical and chemical test such as

dimension measurement, solubility studies and qualitative for free formaldehyde.

8. SUMMARY

CHAPTER 8 CHAPTER 8 CHAPTER 8 CHAPTER 8 SUMMARYSUMMARYSUMMARYSUMMARY


The microspheres equivalent to 150 mg of drug was filled in to the formaldehyde

treated capsule bodies and plugged with HPMC at different concentration (20, 30 and 40

mg). The joint of the capsule body and cap was sealed with small amount of 5 %

ethycellulose ethanolic solution. Then these filled capsules were completely coated with

5 % cellulose acetate phthalate solution. These pulsatile formulations were subjected to

various tests such as thickness of CAP coating, weight variation and in vitro release

studies.

From the in vitro release studies of chrontherapeutic device, it was observed that

with all the formulations, there was absolutely no drug release in simulated gastric fluid

(acidic pH 1.2) for 2 hrs. Negligible amount of drug release was observed in simulated

intestinal fluid (pH 7.4 phosphate buffer), where the dissolution were carried out for 3

hrs. At the end of 15 hrs the cumulative drug release for F5, F6 and F7 formulations was

75.96, 72.01 and 59.92 respectively.

The result obtained promises the development of chronotherapeutic system for

time and pH dependant drug release for the treatement of rheumatoid arthritis. Further

work is to establish the therapeutic utility of this system by pharmacokinetics and

pharmacodynamic studies on human beings.

CHAPTER 9 CHAPTER 9 CHAPTER 9 CHAPTER 9 BIBLIOGRAPHYBIBLIOGRAPHYBIBLIOGRAPHYBIBLIOGRAPHY


1. Gothaskar, AV, Joshi AM, Joshi, NH, 2004. Pulsatile drug delivery system—a review.

Drug Del. Technol. 4, http://www.drugdeliverytech. Com/id article-250.

2. Bi-Botti CY. Chronopharmaceutics: Gimmick or clinically relevant approach to drug

delivery—a review. J Control Rel 2004;98(3):337–53.

3. Bjorn, L. 1996. The clinical relevance of chronopharmacology in therapeutics.

Pharmacological Res.1996;33:107–15.

4. Suresh S, Pathak S. Chronopharmaceutics: Emerging role of biorhythms in optimizing

drug therapy. Indian J Pharm Sci 2005;67(2):135-40.

5. Sharma S, Pawar SA, Low density multiparticulate system for pulsatile release of

meloxicam. Int J Pharm 2006;313: 150-8.

6. Fan TY, Wei SL, Yan WW Chen DB, Li J. An investigation of pulsatile release tablets

with ethycellulose and eudragit-L as film coating materials and cross-linked polyvinyl

pyrolidone in the core tablets. J Control Rel 2001;77:245-51.

7. Krishainah YSR, Satyanarayan S. Colon-specific drug delivery system. In: Jain NK,

editor. Advances in controlled and novel drug delivery. 1st Ed. New Delhi: CBS

publishers and distributors; 2001:89-119.

8. Bhavana V, Khopade AJ, Jain VVD, Jain NK. Oral pulsatile drug delivery. Eastern

pharmacist 1996 Aug;39 (464): 21-6.

9. Smolensky MH, Peppas AN. Chronobiology drug delivery and Chronopharmaceutics.

Adv Drug Delivery 2007;59:825-51.

10. Hrushesky WJM, 1994. Timing is everything. The Sci, 32–7.

9. BIBLIOGRAPHY



11. Roger Walker and Cate Whittlsea. Clinical pharmacy and Therapeutics. Elsevier Health

Sci 4th Ed. 2008:759-76.

12. Harsh Mohan. Textbook of Pathology. Jaypee Brothers, Medical Publishers Ltd. New

Delhi, 4th Ed. 2003:832-8.

13. http://www.arthritiestreatmentandrelief.com

14. Libo Y, James SC, Joseph AF. Colon specific drug delivery: new approaches and in-

vitro/in-vivo evaluation—review. Int J Pharm 2002;235:1–15.

15. Shivkumar HG, Promod KTM, Kashappa GD. Pulsatile drug delivery systems .Indian J

Pharma Edu 2003 July-Sep : 37(3) : 125:8.

16. Sarasija S, Stutie P. Chronotherapeutics: emerging role of biorhythms in optimizing drug

therapy. Indian J Phrma Sci 2000;67:135–40.

17. Wiwattanapatapee R, Luelak Lomlim, Krisanee Saramunee. Dendrimers conjugates for

colonic delivery of 5-aminosalicylic Acid. J Control Rel 2003;(88): 1–9

18. Julie B, Howard, NES, John ME, Gillian P, Fran MB. The tolerability of multiple oral

doses of Pulsincap® capsules in healthy volunteers. J Control Rel.1996;38: 151–8.

19. Sachin Survase, Neeraj Kumar. Pulsatile drug delivery: Current scenario crips 2007; 8:33

20. Krishnaiah YSR, Reddy PBR, Satyanarayana V, Karthikeyan RS. Studies on the

development of oral colon targeted drug delivery systems for metronidazole in the

treatment of amoebiasis. Int J Pharm 2002;236: 43-55.

21. Chien YW. Controlled and Modulated Release Drug Delivery System in Swarbrik J,

Boylan JC Eds. Encyclopedia of Pharmaceutical Technology, Marcel Dekker, New York,

1990:281-313.



22. Sangalli ME, Maroni A, Zema L, Busetti C, Giordano F, Gazzaniga A. In-vitro and in-

vivo evaluation of an oral system for time and / or sitespecific drug delivery. J Control

Rel 2001;73:103-10.

23. Gupta SK, Atkinson L, Theeuwes F, Wong P, Gilbert PJ, Longstreth J. Pharmacokinetics

of verapamil from an osmotic system with delayed onset. Eur J Pharm and

Biopharma1996;42 (1):74-81

24. Ross AC, Macrae RJ, Walther M, Stevens HNE. Chronopharmaceutical drug delivery

from a pulsatile capsule device based on programmable erosion. J Pharm Pharmacol.

2000;52:903-9.

25. Sweetman SC. Martindale The complete drug reference, 33rd Edn. Pharmaceutical Press:

Great Britain; 2002:41-2.

26. Listair CR, Ross JM, Mathias W, Howard NES. Chronopharmaceutical drug delivery

from a pulsatile capsule device based on programmable erosion. J Pharm. Pharmacol

2002;52:903–9.

27. Samanta MK, Suresh NV, Suresh B. Development of Pulsincap Drug Delivery of

salbutamol sulphate for drug tareting. Indian. Pharma Sci 2000;62(2):102-7.

28. Young-II J, Tomoya O, Zhaopeng Hu. Evaluation of an intestinal pressure-controlled

colon delivery capsules prepared by dipping method. J Control Rel 2001;71:75-82.

29. Seshasayan A, Sreenivasa RB, Prasanna R, Ramana Murthy KV. Studies on release of

Rifampicin from Modified Pulsincap Technique. Indian J Pharma Sci 2001:337-9.

30. Sangalli ME, Maroni A, Zema L, Busetti C, et al. 2001. In vitro and in vivo evaluation of

an oral system for time and/or site-specific drug delivery. J Control Rel 2001; 73:103–10.



31. Zahirul Khan MI, Zeljko P, Nevenka K. A pH-dependent colon targeted oral drug

delivery system using methacrylic acid copolymers. I. Manipulation of drug release using

Eudragit® L100-55 and Eudragit® S100 combinations. J Control Rel 1999;58:215–22.

32. Howard NES, Clive GW, Peter GW, Massoud B, Julei SB, Alan CP. Evaluation of

PulsincapTM to provide regional delivery of dofetilide to the human GI tract. Int J

Pharm2002;236:27–34.

33. Libo Y, James SC, Joseph AF. Colon specific drug delivery: new approaches and in

vitro/in vivo evaluation—review. Int J Pharm 2002;235:1–15.

34. Ying-huan Li, Jia-bi Zhu. Modulation of combined release behaviours from a novel

“tablets-in-capsules system”. J Control Rel 2004;50:111- 22.

35. Tomohiro Takaya, Kiyoshi N, Motoki M, Ikuo Ogita, Norko N, Ryoichi Y, et al.

Importance of dissolution process on systemic availability of drugs delivered by colon

delivery system. J Control Rel 1998;50:111-22.

36. Takashi Ishibashi, Kengo I, Hiroaki Kubo, Masakazu M, Hiroyuki Y. Evalution of

colonic absorbability of drugs in dogs using a novel colontargeted delivery

capsules(CTDC) J Control Rel 1999;59:361-76.

37. Jonathan CDS, Alistair CR, Walter K, Richard WB, Ross JM, Howard NES, et al.

Investigating the coating-dependent release mechanism of a pulsatile capsule using NMR

microscopy. J Control Rel 2003; 92:341-7.

38. Matiholimath VS, Dandagi PM, Jain SS , Gadad AP, Kulkarni AR. Time and pH

dependent colon specific, pulsatile delivery o theophylline for nocturnal asthma. Int J

Pharm 2007;328:49-56.



39. Abraham S, Srinath MS. Development of modified pulsincap drug delivery system of

metronidazole for drug targeting Indian J Pharm Sci 2007;69(1):18-23.

40. Srisagul Sungthongjeen S, Satit Puttipipatkhachorn, Ornlaksana Paeratakul, Andrei

Dashevsky, Roland Bodmeier. Development of pulsatile release tablets with swelling and

rupturable layers. J Control Rel 2004:147–59.

41. Krishnaiah YSR, Veer Raju P, Dinesh Kumar B, Bhaskar P, Satyanarayana V.

Development of colon targeted drug delivery systems for Mebendazole. J Control Rel

2001;77: 87–95

42. Satyanarayana S, Rama Prasad YV, Krishnaiah YSR, Trends in colonic drug delivery- a

review. Indian Drugs 1996;33(1):1-10.

43. Rama Prasad YV, Krishnaiah YSR, Satyanarayana S. In-vitro evaluation of guar gum as

a carrier for colon-specific drug delivery. J Control Rel 1998;51:281-87.

44. Krishnaiah YSR, Seetha DA. Guar gum as a carrier for colon specific delivery; influence

of metronidazole tinidazole on in-vitro release of albendazole from guar gum matrix

tablets. And J Pharm. Sci 2001;4(3): 235-43.

45. Leopold CS, Friend DR. In-vitro study for the assessment of poly (Laspartic acid) as a

drug carrier for colon-specific drug delivery. Int J Pharm 1995;126:139-45.

46. Rubinstein A,Radai R. In vitro and in vivo analysis of colon specificity of calcium

pectinate formulations. Eur J Pharm Biopharm 1995;41:291- 295.

47. http://www.drugbankcom./flurbiprofen. Accessed on June 2010.

48. http://www.sciencelab.com/flurbiprofen. Accessed on June 2010.

49. http://www.roehm.com. Accessed on June 2010.



50. Government of India Ministry of Health & Family Welfare. Indian Pharmacopoeia.

Delhi: Controller of Publications; 1996.p: 750, 151.

51. Ainley W, Paul JW. Handbook of pharmaceutical excipients: monograph. 2ed Ed..

London: The pharmaceutical Press; 2000: P.51-2, 128, 138-9, 257, 113, 119.

52. http://www.tradeindia.com. Accessed on June 2010.

53. http://www.huasu.en.chemnet.com. Accessed on June 2010.

54. http://www.adarshguargum.com. Accessed on June 2010.

55. http://www.chemicalbook.com. Accessed on June 2010.

56. http://www.ronasgroup.com. Accessed on June 2010.

57. Dandagi PM, Matiholimath VS, Gadad AP, Kulkarni AR, Jain SS. pH Sensitive

mebeverin microspheres for colon delivery Indian J Phrm Sci 2009;71 (4): 2648.

58. Mehat KA. Formulation of enterosoluble microparticles for an acid labile Protein. J

Pharm Pharmaceut Sci (www.ualberta.ca/~csps) 2002;5(3):234-44.

59. D Nagasamy Venkatesh, Reddy AK, Samanta MK. Development and In Vitro Evaluation

of Colonic Drug Systems for Tegaserod Maleate. Asian J Pharm 2009;Jan – Mar: 50-3.

60. Manavalan ramasamy. physical pharmaceutics. 2nd ed. india :vignesh publisher;2004.

61. Patel A, Ray S, Thakur RM. In vitro evaluation and optimization of controlled release

floating drug delivery system of metformin hydrochloride. DARU 2006;14(2): 57-64.

62. Kothawade KB, Gattani SG, Surana SJ.. Colonic Delivery of Aceclofenac Using

combination of pH and Time Dependent Polymers. Indian Drugs Nov 2009;46 (11): 67

70.

63. Saravanan M, Bhaskar K, Srinivasa Rao G, Dhanaraju MD. Ibuprofen loaded

ethylcellulose / polystyrene microsphers an approch to get prolonged drug release with



reduced burst effect and low ethycellulose content J Microencapsulation 2003;20 (3):

289-302.

64. Nizar Al-Zoubi, Alkhatib HS, Yasser Bustanji, Khaled Aiedeh, Starros Malamataris.

Sustained-release of buspirone HCL by co spray-drying with aqueous polymeric

dispersion. Eur J Pharma and Biopharm 2008;(69): 735-42.

65. Seshasayan A, Sreenivasa RB, Prasanna R., Ramana Murthy KV. Studies on Release of

Rifampicin from modified pulsincap technique. Indian J Pharm Sci 2001:337–9.

CHAPTER 10 CHAPTER 10 CHAPTER 10 CHAPTER 10 ANNEXURESANNEXURESANNEXURESANNEXURES

Department of Pharmaceutics, BharaDepartment of Pharmaceutics, BharaDepartment of Pharmaceutics, BharaDepartment of Pharmaceutics, Bharathi College of Pharmacy thi College of Pharmacy thi College of Pharmacy thi College of Pharmacy 80808080

POSTER PRESENTATIONS

1. Vinay Kumar K V*, Dr. T. Sivakumar, Dr. Tamizh mani T. “Development of

chrono pharmaceutical drug delivery system of flurbiprofen”. International

Conference held on 20th

& 21st August 2010 in PES College.

MANUSCRIPT COMMUNICATION

� Review article

1. Vinay Kumar K V*, T. Sivakumar, Tamizh mani T, Colon Targeting Drug Delivery

System: A Review on Recent Approaches. International Journal of Current

Pharmaceutical Research. (Communicated).

� Research articles

1. Vinay Kumar K.V*, Sivakumar.T, Kavitha.K, Tamizmani.T Formulation and

evaluation of flurbiprofen microspheres for colonic drug delivery system.

International Journal of Current Research and Review. (Communicated).

2. Vinay Kumar K.V*, Sivakumar.T, Kavitha.K, Tamizmani.T. Formulation and

evaluation of chronotherapeutic drug delivery system of flurbiprofen. Der

Pharmacia Sinica. (Communicated).

10. ANNEXURES

Documents

Chronotherapeutic Drug Delivery System of Flurbiprofen