Simple, Rapid and Sensitive UV-Visible Spectrophotometric Method

Hindawi Publishing CorporationJournal of SpectroscopyVolume 2013 Article ID 783457 5 pageshttpdxdoiorg1011552013783457

Research ArticleSimple Rapid and Sensitive UV-Visible SpectrophotometricMethod for Determination of Antidepressant Amitriptyline inPharmaceutical Dosage Forms

Pankaj Soni1 Deepak Sinha2 and Rajmani Patel3

1 Department of Chemistry Government Danveer Tularam College Utai Durg CG 490001 India2Department of Chemistry Government Nagarjun PG Science College Raipur CG 492001 India3 Department of Chemistry Government College Bhanpuri Bastar CG 494224 India

Correspondence should be addressed to Rajmani Patel rajmanipatelgmailcom

Received 5 May 2013 Accepted 11 July 2013

Academic Editor Lahcen Bih

Copyright copy 2013 Pankaj Soni et al This is an open access article distributed under the Creative Commons Attribution Licensewhich permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited

The paper describes a new and simple approach for spectrophotometric determination of tricyclic antidepressant drugamitriptyline Enhancement of the colour intensity of the Fe(III)-SCNminus complex on addition of the drug amitriptyline forms thebasis of the proposed method The value of molar absorptivity of the Fe(III)-SCNminus amitriptyline ion pair complex in terms of thedrug lies in the range of (282ndash336) times 103 Lsdotmolminus1sdotcmminus1 at the absorptionmaximum 460 nmThe detection limit of the method was03120583gsdotmLminus1 The slope intercept and correlation coefficients for the present method were found to be 0008 0002 and +0998respectively The effect of analytical variables on the determination of the drug and the composition of the complex are discussedin the paper The method is applicable in the determination of amitriptyline in pharmaceutical preparations

1 Introduction

Amitriptyline [3-(1011-dihydro-5H-dibenzol[ad]cyclohept-5-ylidene) propyldimethylamine] constitutes an importantclass among the neurotherapeutics belonging to first gen-eration of antidepressant drug [1 2] Recent studies showproinflammatory cytokine process takes place during clinicaldepression mania and bipolar disorder and it is possiblethat symptoms of these conditions are attenuated by thepharmacological effect of antidepressants on the immunesystem [3ndash8] Amitriptyline has a carboxylic structure withan exocyclic double bond at C-5 which is substituted with anN N-dimethyl-1-propanamino side chain (Figure 1)

Amitriptyline hydrochloride [AMIYTP]Cl represents alarge group of compounds used in treatment of various men-tal diseasesThe chemical structure of this compound is basedon the condensed aromatic three-ring system which includessubstituents in positions 2 and 10 The difference in chemicalstructure causes the different pharmaceutical activity of drugThe value of angle of these molecules is important the morenearly planar the greater the neuroleptic activity It is believed

that drug amitriptyline acts by blocking the receptors of neu-rotransmitters noradrenalin in the synopsis in the centralnervous system which results in an increase of concentrationof both molecules with a subsequent enhancement of theirantidepressant potency However this drug suffers fromseveral drawbacks such as antiarrhythmic anticholinergiccardiovascular and hyperthermia side effect which may bereduced if the drugs are suitably vectored to the organism

Various analytical methods have been reported for deter-mination of amitriptyline including spectrofluorimetric [9]spectrophotometric [10ndash15] flow injection method [16]UV-Visible spectrophotometric methods [17 18] based onchromogenic reaction with citric acid-acetic anhydride [19]bromothymol blue [20] ammonium reineckate [21 22]bismuth-hexaiodide [23] and cerium (IV) [24] Most ofthese methods however suffer from several interferences bymany basic compounds until several manipulation stepsand can be applied only to relatively high concentrationof drugs Some of these methods are not simple for theroutine analysis and they need sophisticated instrumentswhich are not commonly available in the routine laboratories

2 Journal of Spectroscopy

N

Figure 1 Amitriptyline

and conventional batch process solvent extraction is a tediousand time-consuming procedureTherefore it seems necessaryto develop a simple and fast identification method for deter-mination of amitriptyline The proposed method is basedon the enhancement of the colour intensity of the Fe(III)-SCNminus complex on addition of the drug amitriptyline Theoptimization of analytical variables is discussed in this paperThemethod is simple sensitive and found to be reproducibleThis method has been applied for determination of the con-centration of amitriptyline in pharmaceutical preparations

2 Experimental

21 Apparatus Systronics (India) make UV-Visible dou-ble beam spectrophotometermdashmodel 2201 with quartz cellhaving path length of 1 cm was employed to determinethe absorbance Source and sample positions are software-optimized to keep the unit always at its peak performance

22 Reagents All chemical used were of analytical gradereagent (Merck) Deionized double distilled water was usedthroughout the experiment Glass wares were cleaned withacidified solutions of KMnO

4

or K2

Cr2

O7

followed bywashing with concentrated HNO

3

and rinsed several timeswith deionized double distilled water All solutions used wereprior filtered and degassed

221 Standard Solution of Amitriptyline (1mgsdotmLminus1 or1000 ppm) The standard solution (1mgsdotmLminus1 or 1000 ppm)of amitriptyline (Mol Wt 319) was prepared by dissolving10 gm amitriptyline in 1 litre deionized double distilled waterThe working solutions of amitriptyline were prepared by theappropriate dilution of the stock solution

222 Reagent Solution Ammonium Thiocyanate (18M) Itwas prepared fresh by dissolving 14 gm ammonium thio-cyanate in 100mL deionized double distilled water

223 Reagent Solution of Iron(III) 125 times 10minus3M It is pre-pared by dissolving 00506 gm of Fe(NO

3

)3

sdot9H2

O (Mol Wt404) in 001M nitric acid andmade up the solution to 100mLwith 001M nitric acid solution

23 Procedure 25mL aliquots of the standard solutionsof amitriptyline having varying concentrations from 10 to100 120583gmLminus1 were taken in the 25mL volumetric flasks Ineach volumetric flask 25mL of the iron solution and 5mL ofNH4

SCN solution were added then made up the solutionsupto the mark on volumetric flask with double distilledwater then measured the absorbance at 460 nm against thereagent blank and prepared the calibration graph by plottingabsorbance versus concentration of amitriptyline (Figure 2)The similar procedure was repeated with the sample solutionwhich was prepared from the pharmaceutical product Theconcentration of amitriptyline in the sample solution wascomputed by using the calibration curve prepared undersimilar condition

3 Results and Discussion

31 ReactionMechanism and Composition of Complex Ferricions react with SCNminus ions to give a variety of red-orangecomplexes but the presence of amitriptyline activates theformation of a higher thiocyanato species which enhancesthe colour intensity of the complex The proposed reactionfor the formation of higher thiocyanato complex in presenceof the drug cation that is [AMIYTP]+ can be expressed as

Fe3+ + 119899SCNminus + 119898[AMIYTP]+

999445999468 [Fe(SCN)119899

]3minus119899

sdot 119898[AMIYTP]+(1)

where the value of 119899may vary from 2 to 6This reaction has been used for the determination of

cationic antidepressant drug in the present workThe mole ratios of Fe(III) to SCNminus and [AMIYTP]+

ions involved in formation of the ion-associated complexwere determined on the basis of the spectrophotometricanalysis of these constituents at their different concentrationsThe values of 119860eq (the absorbance of the complex whenthe reagent was in equilibrium) and 119860max (the absorbancewhen the reagent was in constant excess) were determinedspectrophotometrically and the values of (119860eq119860max minus 119860eq)

were calculated for different concentrations of Fe(III) SCNminusand [AMIYTP]+ Their molar ratio was determined usingcurve-fittingmethod by plotting log (119860eq119860maxminus119860eq) versuslog119872 (where119872 =molar concentration) values of SCNminus and[AMIYTP]+ The values of slope for SCNminus and [AMIYTP]+were found to be 42 and 07 close to integers 4 and 1respectively For each mole of Fe(III) the involvement ofSCNminus and [AMIYTP]+ was assumed to be 4 1 Hence thecurve-fitting method suggested the molar ratio of Fe(III)SCNminus and drug cation in the complex to be in 1 4 1 ratiorespectively (Figures 3 and 4)

The probable reaction which occurred in the followingsolution in HNO

3

medium is expressed as

Fe3+ + 4SCNminus + (AMIYTP)+ + 119899NO3

minus

999445999468 [Fe(SCN)4

sdot (AMIYTP)+] (NO3

)119899

119899minus

(2)

where value of ldquo119899rdquo may vary from 1 to 3 and (AMIYTP)+ =cation of the drug amitriptyline

Journal of Spectroscopy 3

0

001

002

003

004

005

006

007

008

009

01

0 1 2 3 4 5 6 7 8 9 10Concentration of amitriptyline (120583g mLminus1)

Abso

rban

ce at

(460

nm)

Figure 2 Calibration graph for determination of amitriptyline 10to 100120583gmLminus1

0

02

04

06

08

1

0 005 01 015 02 025

logM (SCNminus)minus02

log(A

eqA

maxminusA

eq)

Figure 3 Curve-fitting method for the determination of mole ratioof the Fe(III) to SCNminus in the Fe(III)-SCNminus-[AMIYTP]+ complex

32 Absorption Spectra The Fe(III)-SCNminus-[AMIYTP]+complex exhibits the absorption maximum at 460 nm(Figure 5) The position of 120582max did not change whenthe drug amitriptyline is added but the absorbance wasincreased In presence of the drug a hyperchromic shift wasobserved due to formation of a higher thiocyanate complex

33 Optimization of Analytical Variables Among the acids(HCl H

2

SO4

and HNO3

) tested during the investigationHNO

3

was found most suitable because of the better perfor-mance of the complex in the nitric acid medium Anotherreason for the selection of nitric acid is its oxidizing naturebecause of which several reductants that is CNminus S2minus S

2

O3

2minusoxalic acid ascorbic acid and so forth did not interfere inthe reaction Use of 001M nitric acid in the iron solutionwas found adequate during the detailed investigation Duringthe optimization of analytical variables the minimum con-centrations of iron(III) and ammonium thiocyanate solutions(required to obtain the maximum and stable absorbance)

0020406081

0minus18minus16minus14minus12minus1minus08minus06minus04minus02

log(A

eqA

maxminusA

eq)

minus7 minus6 minus5 minus4 minus3 minus2 minus1logM (AMIYTP+)

Figure 4 Curve-fitting method for the determination of moleratio of the Fe(III) to [AMIYTP]+ in the Fe(III)-SCNminus-[AMIYTP]+complex

0000

0010

0020

0030

0040

0050

0060

0070

0080

0090

Wavelength (nm)

Abso

rban

ce

280

300

320

340

360

380

400

420

440

460

480

500

520

540

560

580

600

Figure 5 Absorption spectra of the Fe(III)-SCNminus and Fe(III)-SCNminus-[AMIYTP]+ complexes (concentration of amitriptyline =5 120583gmLminus1)

were found to be 125 times 10minus3M and 18M respectively Theirfurther addition decreased the absorbance As the solutionof ammonium thiocyanate seemed to be slightly viscous incomparison with the iron(III) solution the SCNminus solutionwas prepared using double volume of distilled water Thusvolume of 25mL of 125 times 10minus3M iron(III) and 50mL of18M ammonium thiocyanate solutions was applied in orderto avoid the matrix interference during analysis

34 Optimum Concentration Range Detection Limit andStatistics The absorbances for the different concentrationsof amitriptyline are shown in Figure 2 The method followedlinearity in the range 10 to 100 120583gmLminus1 of amitriptylinewith the slope intercept and correlation coefficient of0008 0002 and +0998 respectively The value of molarabsorptivity (calculated by taking the molar concentrationof amitriptyline and path length of the cell to be 1 cm) withamitriptyline in terms of the drugwas found to be in the range(282ndash336) times 103 Lmolminus1 cmminus1 at the absorption maximum460 nm The detection limit (absorbance gt3 times SD) of themethod was 03120583gmLminus1 The relative standard deviation for


Table 1 The results of analysis of ldquoAmitriptylinerdquo tablets by proposed and official methods

S No Pharmaceutical product Recovery mg Error Official method Proposed method

(1) Amit-25 25mg 253 plusmn 003 248 plusmn 016 16(2) Amitriptyline hydrochloride tablet 25mg 252 plusmn 025 247 plusmn 032 19

Table 2 Performance data for spectrophotometric determination of amitriptyline

S No Method 120582max(nm) Working range(120583g mLminus1) RSD () Correlation coefficient

(1) Extraction-spectrophotometric ammoniumreineckate method (official method) 523 01ndash60 08 0994

(2) Proposed spectrophotometric Fe(III)-SCNminus method 460 10ndash120 170 0998

the analysis of six different solutions containing 50 120583gmLminus1amitriptyline was found to be plusmn17

4 Application of the Method

The proposed method was applied for the determination ofamitriptyline in commercial pharmaceutical tablets Amil-25(Mano Pharmacy India) and Amitriptyline hydrochloridetabletUSPIP-25mg (From (Iron) drugs andpharmaceuticalsPvt Ltd India) Sample solutions were prepared from thetablets Five tablets of each product were weighed andpowdered The powder equivalent to their single tablet wasdissolved in methanol and the obtained solution was filteredand evaporated to dryness Then the residue was dissolvedin distilled water and made up the volume up to 100mL in avolumetric flask These stock solutions were further dilutedto contain the requisite concentrations Then the proceduredescribed earlier for the determination of amitriptylinefollowed and it was compared with the results obtainedfrom the official method as shown in Tables 1 and 2 Theamitriptyline content determined by the proposedmethod inthe drug samples was in excellent agreement with the alreadyreported extractive spectrophotometric ammonium reineck-ate method (Table 1) The performance of the proposedmethod was compared with the official method (Table 2)

5 Conclusion

Themethodwas successfully applied for the determination ofamitriptyline in the pharmaceutical preparationThemethodis very simple as there is no requirement of prior separationor extraction of the complex and the reagents are low costand commonly available in routine laboratories The resultsobtained from the proposed method were comparable withthe established methods The method has good potential insimplicity sensitivity and reproducibility and the reactionused in the proposed work is expected to give better resultswith flow injection analysis

Acknowledgments

Theauthors are thankful to theDirector Shri ShankaracharyaCollege of Engineering and Technology Bhilai (CG) for

providing laboratory facilities for this work They are alsothankful to the All India Council for Technical Education(AICTE) NewDelhi for financial support during the presentinvestigation

References

[1] R J Baldessarini ldquoDrugs and the treatment of psychiatricdisorders depression and maniardquo in Goodman amp Gilmanrsquos ThePharmacological Basis of Therapeutics J G Hardman L ELimbird P B Molinoff R W Ruddon and A G Gilman Edschapter 19 pp 431ndash459 McGraw Hill New York NY USA 9thedition 1996

[2] C D Las Cuevas W Penate and E J Sanz ldquoPsychiatric outpa-tientsrsquo self-reported adherence versus psychiatristsrsquo impressionson adherence in affective disordersrdquo Human Psychopharmacol-ogy Clinical and Experimental vol 28 no 2 pp 142ndash150 2013

[3] A Remlinger-Molenda P Wojciak M Michalak and JRybakowski ldquoActivity of selected cytokines in bipolar patientsduring manic and depressive episodesrdquo Psychiatria Polska vol46 no 4 pp 599ndash611 2012

[4] S M OrsquoBrien P Scully L V Scott and T G Dinan ldquoCytokineprofiles in bipolar affective disorder focus on acutely illpatientsrdquo Journal of Affective Disorders vol 90 no 2-3 pp 263ndash267 2006

[5] E Obuchowicz A Marcinowska and Z S Herman ldquoAntide-pressants and cytokinesmdashClinical and experimental studiesrdquoPsychiatria Polska vol 39 no 5 pp 921ndash936 2005

[6] C-J Hong Y W-Y Yu T-J Chen and S-J Tsai ldquoInterleukin-6 genetic polymorphism and Chinese major depressionrdquo Neu-ropsychobiology vol 52 no 4 pp 202ndash205 2005

[7] I J Elenkov D G Iezzoni A Daly A G Harris and GP Chrousos ldquoCytokine dysregulation inflammation and well-beingrdquo NeuroImmunoModulation vol 12 no 5 pp 255ndash2692005

[8] M Kubera M Maes G Kenis Y-K Kim and W LasonldquoEffects of serotonin and serotonergic agonists and antagonistson the production of tumor necrosis factor120572 and interleukin-6rdquoPsychiatry Research vol 134 no 3 pp 251ndash258 2005

[9] F A Mohamed H A Mohamed S A Hussein and S AAhmed ldquoA validated spectrofluorimetric method for determi-nation of some psychoactive drugsrdquo Journal of Pharmaceuticaland Biomedical Analysis vol 39 no 1-2 pp 139ndash146 2005

[10] J Karpinska and J Suszynska ldquoThe spectrophotometric simul-taneous determination of amitryptyline and chlorpromazine


hydrochlorides in their binary mixturesrdquo Journal of Trace andMicroprobe Techniques vol 19 no 3 pp 355ndash364 2001

[11] F A F Nour El-Dien G G Mohamed and N A MohamedldquoSpectrophotometric determination of trazodone amineptineand amitriptyline hydrochlorides through ion-pair formationusing methyl orange and bromocresol green reagentsrdquo Spec-trochimica Acta Part A vol 65 no 1 pp 20ndash26 2006

[12] T Aman A A Kazi M I Hussain S Firdous and I U KhanldquoSpectrophotometric determination of amitriptyline-HCl inpure and pharmaceutical preparationsrdquo Analytical Letters vol33 no 12 pp 2477ndash2490 2000

[13] J OOnah ldquoSpectrophotometric determination of amitriptylineby themethod of charge-transfer complexation with chloranilicacidrdquo Global Journal of Pure and Applied Sciences vol 11 no 2pp 237ndash240 2005

[14] D J Patel and V Patel ldquoSimultaneous estimation of amitripty-lineHCl and perphenazine in tablets byUV-Visible spectropho-tometric and HPTLCrdquo International Journal of PharmaceuticalSciences and Research vol 1 no 2 pp 20ndash23 2010

[15] P Venkatesan P V R S Subrahmanyam and D RaghuPratap ldquoSpectrophotometric determination of pure amitripty-line hydrochloride through ligand exchange on mercuric ionrdquoInternational Journal of ChemTech Research vol 2 no 1 pp 54ndash56 2010

[16] R M El-Nashar N T Abdel Ghani and A A BioumyldquoFlow injection potentiometric determination of amitriptylinehydrochloriderdquo Microchemical Journal vol 78 no 2 pp 107ndash113 2004

[17] D J Patel and V Patel ldquosimultaneous estimation of amitripty-line hydrochloride and perphenazine by absorption ratio (Q-analysis) UV spectrophotometric method in combined tabletdosage formrdquo International Journal of Pharmaceutical Sciencesand Research vol 1 no 12 pp 133ndash137 2010

[18] B Starczewska and A Jasinska ldquoAnalytical application of thereactions of amitriptyline with eriochrome cyanine R andpyrocatechol violetrdquo Acta Poloniae Pharmaceutica vol 60 no6 pp 417ndash423 2003

[19] Y A Beltagg ldquoColorimetric determination of tricyclic antide-pressant and dibenzazepine and dibenzmdashcycloheptadine withcitric acidmdashacetic anhydriderdquo Pharmazie vol 31 pp 483ndash4881976

[20] WN French FMatsui and J F Truelove ldquoFlow-injection spec-trophotometric determination of amitriptyline hydrochloriderdquoCanadian Journal of Pharmaceutical Sciences vol 3 no 3 pp33ndash37 1968

[21] E Domagalina and L Przyborowski ldquoFlow injection extractivespectrophotometric determination of antidepressant amitripty-line hydrochloriderdquo Chemia Analityczna vol 7 pp 1153ndash11591962

[22] E M Elnemma F M El Zawawy and S S M Hassan ldquoDeter-mination of amitriptyline imipramine and orphenadrine inantidepressant drugs by potentiometry spectrophotometry andatomic absorption spectrometryrdquo Mikrochimica Acta vol 110no 1-3 pp 79ndash88 1993

[23] B Dembinski ldquoExtractive colorimetric determination ofamitriptyline and imipramine hydrochloride with bismuth hexiodiderdquoActa Poloniae Pharmaceutica vol 34 pp 509ndash514 1977

[24] H E Hamilton J E Wallace and K Blumk ldquoSpectropho-tometric and gas-liquid chromatographic determination ofamitriptylinerdquoAnalytical Chemistry vol 47 no 7 pp 1139ndash11441975

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

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Advances in

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Hindawi Publishing Corporationhttpwwwhindawicom

Analytical Methods in Chemistry

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Bioinorganic Chemistry and ApplicationsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

SpectroscopyInternational Journal of


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Applied ChemistryJournal of



Theoretical ChemistryJournal of


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Spectroscopy

Analytical ChemistryInternational Journal of


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Quantum Chemistry


Organic Chemistry International

ElectrochemistryInternational Journal of



CatalystsJournal of


N

Figure 1 Amitriptyline

and conventional batch process solvent extraction is a tediousand time-consuming procedureTherefore it seems necessaryto develop a simple and fast identification method for deter-mination of amitriptyline The proposed method is basedon the enhancement of the colour intensity of the Fe(III)-SCNminus complex on addition of the drug amitriptyline Theoptimization of analytical variables is discussed in this paperThemethod is simple sensitive and found to be reproducibleThis method has been applied for determination of the con-centration of amitriptyline in pharmaceutical preparations

2 Experimental

21 Apparatus Systronics (India) make UV-Visible dou-ble beam spectrophotometermdashmodel 2201 with quartz cellhaving path length of 1 cm was employed to determinethe absorbance Source and sample positions are software-optimized to keep the unit always at its peak performance

22 Reagents All chemical used were of analytical gradereagent (Merck) Deionized double distilled water was usedthroughout the experiment Glass wares were cleaned withacidified solutions of KMnO

4

or K2

Cr2

O7

followed bywashing with concentrated HNO

3

and rinsed several timeswith deionized double distilled water All solutions used wereprior filtered and degassed

221 Standard Solution of Amitriptyline (1mgsdotmLminus1 or1000 ppm) The standard solution (1mgsdotmLminus1 or 1000 ppm)of amitriptyline (Mol Wt 319) was prepared by dissolving10 gm amitriptyline in 1 litre deionized double distilled waterThe working solutions of amitriptyline were prepared by theappropriate dilution of the stock solution

222 Reagent Solution Ammonium Thiocyanate (18M) Itwas prepared fresh by dissolving 14 gm ammonium thio-cyanate in 100mL deionized double distilled water

223 Reagent Solution of Iron(III) 125 times 10minus3M It is pre-pared by dissolving 00506 gm of Fe(NO

3

)3

sdot9H2

O (Mol Wt404) in 001M nitric acid andmade up the solution to 100mLwith 001M nitric acid solution

23 Procedure 25mL aliquots of the standard solutionsof amitriptyline having varying concentrations from 10 to100 120583gmLminus1 were taken in the 25mL volumetric flasks Ineach volumetric flask 25mL of the iron solution and 5mL ofNH4

SCN solution were added then made up the solutionsupto the mark on volumetric flask with double distilledwater then measured the absorbance at 460 nm against thereagent blank and prepared the calibration graph by plottingabsorbance versus concentration of amitriptyline (Figure 2)The similar procedure was repeated with the sample solutionwhich was prepared from the pharmaceutical product Theconcentration of amitriptyline in the sample solution wascomputed by using the calibration curve prepared undersimilar condition

3 Results and Discussion

31 ReactionMechanism and Composition of Complex Ferricions react with SCNminus ions to give a variety of red-orangecomplexes but the presence of amitriptyline activates theformation of a higher thiocyanato species which enhancesthe colour intensity of the complex The proposed reactionfor the formation of higher thiocyanato complex in presenceof the drug cation that is [AMIYTP]+ can be expressed as

Fe3+ + 119899SCNminus + 119898[AMIYTP]+

999445999468 [Fe(SCN)119899

]3minus119899

sdot 119898[AMIYTP]+(1)

where the value of 119899may vary from 2 to 6This reaction has been used for the determination of

cationic antidepressant drug in the present workThe mole ratios of Fe(III) to SCNminus and [AMIYTP]+

ions involved in formation of the ion-associated complexwere determined on the basis of the spectrophotometricanalysis of these constituents at their different concentrationsThe values of 119860eq (the absorbance of the complex whenthe reagent was in equilibrium) and 119860max (the absorbancewhen the reagent was in constant excess) were determinedspectrophotometrically and the values of (119860eq119860max minus 119860eq)

were calculated for different concentrations of Fe(III) SCNminusand [AMIYTP]+ Their molar ratio was determined usingcurve-fittingmethod by plotting log (119860eq119860maxminus119860eq) versuslog119872 (where119872 =molar concentration) values of SCNminus and[AMIYTP]+ The values of slope for SCNminus and [AMIYTP]+were found to be 42 and 07 close to integers 4 and 1respectively For each mole of Fe(III) the involvement ofSCNminus and [AMIYTP]+ was assumed to be 4 1 Hence thecurve-fitting method suggested the molar ratio of Fe(III)SCNminus and drug cation in the complex to be in 1 4 1 ratiorespectively (Figures 3 and 4)

The probable reaction which occurred in the followingsolution in HNO

3

medium is expressed as

Fe3+ + 4SCNminus + (AMIYTP)+ + 119899NO3

minus

999445999468 [Fe(SCN)4

sdot (AMIYTP)+] (NO3

)119899

119899minus

(2)

where value of ldquo119899rdquo may vary from 1 to 3 and (AMIYTP)+ =cation of the drug amitriptyline


0

001

002

003

004

005

006

007

008

009

01


Abso

rban

ce at

(460

nm)


0

02

04

06

08

1

0 005 01 015 02 025


log(A

eqA

maxminusA

eq)




2

SO4

and HNO3


3


2

O3


0020406081


log(A

eqA

maxminusA

eq)



0000

0010

0020

0030

0040

0050

0060

0070

0080

0090

Wavelength (nm)

Abso

rban

ce

280

300

320

340

360

380

400

420

440

460

480

500

520

540

560

580

600















5 Conclusion


Acknowledgments



References




































Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of


0

001

002

003

004

005

006

007

008

009

01


Abso

rban

ce at

(460

nm)


0

02

04

06

08

1

0 005 01 015 02 025


log(A

eqA

maxminusA

eq)




2

SO4

and HNO3


3


2

O3


0020406081


log(A

eqA

maxminusA

eq)



0000

0010

0020

0030

0040

0050

0060

0070

0080

0090

Wavelength (nm)

Abso

rban

ce

280

300

320

340

360

380

400

420

440

460

480

500

520

540

560

580

600















5 Conclusion


Acknowledgments



References




































Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of












5 Conclusion


Acknowledgments



References




































Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of


























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of










Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of

Documents

Simple, Rapid and Sensitive UV-Visible Spectrophotometric Method