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Protein Encapsulation using Pressurized CO 2 based Processes: Challenges and Perspectives Frank BOURY University ofAngers Biomimetic Micro-Nanomedicines INSERM U1066 [email protected] Colloque ADEBIOTECH Stabilité et formulation des protéines et peptides 23-24 October 2015, Romainville 1

Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

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Page 1: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

Protein Encapsulation using Pressurized CO2 based Processes: Challenges and Perspectives

Frank BOURY

University ofAngers

Biomimetic Micro-Nanomedicines

INSERM U1066

[email protected]

Colloque ADEBIOTECH

Stabilité et formulation des protéines et peptides 23-24 October 2015, Romainville

1

Page 2: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

SUMMARY

• What is a supercritical CO2 and its advantages ?

• The main issues in protein encapsulation

• ScCO2 as a W/C emulsion continuous phase and reactant – Protein encapsulation into PLGA microspheres

– Protein encapsulation into calcium carbonate microparticles

– Preliminary evaluation for application in tissue engineering (cartilage)

• Perspectives and conclusions

2

Page 3: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

What is a Supercritical Fluid?

Définition: The supercritical region refers to the state of compound which is

above its critical pressure and critical temperature

Liquid-like properties (high density)

Gas-like properties (high diffusivity, low

viscosity)

Tunable solvent strength (density) by adjusting both the pressure and

temperature

3

Page 4: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

Applications of CO2

CO2 Technology

Extraction Polymers processing

Anti-solvent processes

Polymerization

Polymers modification

Polymers foaming

CO2 as chemical

CO2 as monomer

4

Page 5: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

SUMMARY

• What is a supercritical CO2 and its advantages

• The main issues in protein encapsulation

• ScCO2 as a W/C emulsion continuous phase and reactant – Protein encapsulation into PLGA microspheres

– Protein encapsulation into calcium carbonate microparticles

– Preliminary evaluation for application in tissue engineering (cartilage)

• Perspectives and conclusions

5

Page 6: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

To take into protein unstabilities and

solvent toxicity in formulation processes

Solvant

Limit

concentration(p

pm)

LD50 (mg/kg) oral

route, rat

LD 50

(mg/kg)

Acetonitrile 410 2460 1680 (iv)

Methylene

chlorhide 600 1600

Acetone

5000

5800 5500 (iv)

Ethyle acétate 5620

Tetrahydrofural 1650 2900 (ip)

Polymer solution

Aqueous solution

Interface → emulsion

CO2

GREEN PROCESSES

6

Page 7: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

SUMMARY

• What is a supercritical CO2 and its advantages

• The main issues in protein encapsulation

• ScCO2 as a W/C emulsion continuous phase and reactant

– Protein encapsulation into PLGA microspheres

– Protein encapsulation into calcium carbonate microparticles

– Preliminary evaluation for application in tissue engineering (cartilage)

• Perspectives and conclusions

7

Page 8: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

8

1) extraction

2) Dépressurisation

5

Solvent+polymer+ API

o Emulsion polar liquid-in-scCO2

scCO2

C

W

May involve stabilizers

Eastoe et al., Microemulsions with CO2 as a solvent, Curr. Opin. Colloid Interface Sci., 2012, 17, 266–273

Particles formed from an emulsion with ScCO2 as

the continuous phase

But what about toxicity?

Solvent solubility in C02 (P,T) Extraction media (water, ethanol…)

8

Page 9: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

SUMMARY

• What is a supercritical CO2 and its advantages

• The main issues in protein encapsulation

• ScCO2 as a W/C emulsion continuous phase and reactant – Protein encapsulation into PLGA microspheres

– Protein encapsulation into calcium carbonate microparticles

– Preliminary evaluation for application in tissue engineering (cartilage)

• Perspectives and conclusions

9

Page 10: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

Use of non toxic solvent

Solvent LD50 (ml/kg)

Hemolytic

activity

IV route

Cardiovascular

toxicity IV route

Angiotoxiciy in

comparaison with

DMSO

Vasosapme (min)

Diméthyle sulfoxide 6.9 (iv./m), 12.6

(ip./m), 15(po./m) Very high Moderate 19.1

N-méthyl pyrrolidone 4.4 (ip./m) Moderate Toxicity + 5 (*)

Glycofurol 3.5 (iv./m) Moderate Toxicity -- 10.5

Diméthyle isosorbide 8.54 (iv./r) Low Toxicity -- 5.9 (*)

Polyéthylène glycol

200

7.6 (iv./m), 12.9

(ip./m), 26

(po./m)

Low Toxicity - 1010

(*)Signicant difference between DMI / NMP et DMSO (P<0.05)

Iv, ip, po : Intrvenous, Intraperitoneal, oral ; m, r : mouse, rat

DMI : less toxic solvent, miscible with water (1x103 g/L ;25oC), non

flammable, non volatile (boiling T° : 234-242oC) 10

Page 11: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

Doehlert matrix

X1(ionic strength)

X2 (aqueous volume)

X3 (protein quantity)

1/Protein nanoprecipitation :

SEM image of lysozyme-nanoprecipitates

Protein solution

GF or DMI

Suspension of nanoprecipitates/solvents

non-volatile, injectable

Suspension of nanoprecipitates/ PLGA-solvent(s)

Polymer solution/ DMI or TG

Protein encapsulation in PLGA microparticles “solid dispersion is more stable than molecular state”

Giteau, A., et al., Reversible protein precipitation to ensure stability during encapsulation within PLGA microspheres. European Journal of Pharmaceutics and Biopharmaceutics, 2008. 70(1): p. 127-136. 11

Page 12: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

2/Formulation of PLGA MPs in CO2 pressurized:

Step 1: emulsification in CO2 pressurized.

Step 2: extraction using an aqueous solution.

Patent WO2007072106, Boury F. et al, Method for preparing microparticles from an

emulsion in supercritical or liquid CO2

CO2

1. Introduction of 0.3 ml suspension

2. Pressurization

3.Injection x ml of C2H5OH

Suspension of nanoprecipitates/polymer solution

C 2 H 5 OH

Stirring 4. Injection of 2ml Lutrol 1%/glycin buffer pH10

5. Depressurization 6.Collecting of microparticles suspension in Lutrol 1%. …

Lutrol 1%

thermostated.

25 min

Tran MK, Swed A, Boury, Preparation of polymeric particles in CO2 medium using non-toxic solvents: Formulation and comparisons with a phase separation method , F., Eur J Pharm Biopharm. 2012

Protein encapsulation in PLGA microparticles

12

Page 13: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

25°C, 63bar, 0,3 ml C2H5OH

100% GF

20°C, 58 bar, 0,15 ml C2H5OH

100% GF

19°C,53 bar, 0,15ml C2H5OH

39.5°C, 82bar, 0,15 ml C2H5OH

GF-DMI (1:2/v:v)

Microparticle observation with SEM

« Fingerprint » of an emulsification step

Tran MK, Swed A, Boury, Preparation of polymeric particles in CO2 medium using non-toxic solvents: Formulation and comparisons with a phase separation method , F., Eur J Pharm Biopharm. 2012

EncapsulationYield (max) ≈85%

13

Page 14: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

SEM images of PLGA microparticles during the release study; after 1 week (A, B); after 2 weeks (C, D) and after 4 weeks (E, F).

Effect of unloaded PLGA microparticles on percentage viability of HS68, NIH3T3 and hATSC cells after 48 h of incubation as evaluated by a PicoGreen® assay.

A. Swed et al./International Journal of Pharmaceutics 493 (2015) 357 –365

Application to therapeutic proteins

14

Page 15: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

SUMMARY

• What is a supercritical CO2 and its advantages

• The main issues in protein encapsulation

• ScCO2 as a W/C emulsion continuous phase and reactant – Protein encapsulation into PLGA microspheres

– Protein encapsulation into calcium carbonate microparticles

– Preliminary evaluation for application in tissue engineering (cartilage)

• Perspectives and conclusions

15

Page 16: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

Gene delivery

Cancer therapy

CaCO3

Diagnostic

Bioprobing

Bioimaging

Biosensoring

Drug delivery

Differrent axes of CaCO3 applications as drug delivery system

16

Page 17: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

Vaterite

Phase transition Co-precipitation Adsorption-I mpregnation

Physical Chemical

NH

+ +

+ +

+

+

+

+

+

+

+ +

+

+

+

+

- - -

N H

NH

c

- - -

- -

- - - -

- - -

- - -

- - -

Calcite

I nterfacial reaction

I nner Water Phase

Outer Water Phase

W/ O E mulsion

W/ O/ W E mulsion

! CaCl2

! (NH4)2CO3

! K2CO3

Oil Phase

CaCO 3 microcapsules

Protein

HO

H O

HO

H O

Protein or macromolecule

FUJIWARA M., et al., Chemical Engineering Journal, 2008, 137, 14-22. FUJIWARA M., et al., Crystal Growth & Design, 2010, 10, 4030-4037.

VOLODKIN D. V., et al., Biomacromolecules, 2004, 5, 1962-1972. LOPEZ-MARZO A., et al., Journal of Materials Chemistry, 2012, 22, 15326-15335.

DE TEMMERMAN M.-L., et al., Biomacromolecules, 2011, 12, 1283-1289

Different loading modes of drugs within CaCO3 particles

17

Page 18: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

Emulsion H2O/CO2

SC-CO2 continous medium

Solution of Ca2+

SC-CO2

Ca2+ Ca2+

Ca2+

Ca2+ Ca2+

OH-

OH-

Hyaluronic acid:Template Protein

OH-

HCO3- CO3

-2

H2O

H+

H+

Vaterite nanoaggregates

The carbonation route

Supercritical CO2 process Continuous CO2 gas bubbling

(1) Thermostat-Stirring bath

(2) CO2 pump

(3) pH/Thermo-meter

(4) Optical flow-cell : = 850 nm

(1) Autoclave

(2) High pressure membrane pump

(3) Heat exchanger

(4) HPLC pumpc

(3)

(4)

(1)

(2)

CO2

Beuvier et al. , Journal of Materials Chemistry 2011

18

Page 19: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

PEI

AH

Mesoporosity

Polymorphism

CaCO3 properties

Beuvier et al J. Mater. Chem., 2011, 21, 9757

E. Chavez et al, J. Applied Crist., (2012). 45,881-889

5µm

19

Page 20: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

Formation of CaCO3 microparticles

In situ analysis : effect of pH

Beuvier et al, Anal.Chem. 2014, 86, 9895−9900

20

Page 21: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

Analyses in situ

• X-Ray Diffusion (saxs)

Equipment

2 reactors 60mL

5µm V1 V2

CO2

RX Calcium

Solution

Pressure increase

V2

RX

V1

Pressure decrease

Formation of CaCO3 : in situ study of the

cristallisation process (coll. A. GIBAUD, LPEC, Le Mans)

21

Page 22: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

1 year 2 years 3 years

Lysozyme encapsulation in CaCO3 microparticles

Influence of the formulation process

22

Page 23: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

0

10

20

30

40

50

60

70

HPLC Micrococcus lysodeikticus

Ly

so

zy

me

en

ca

ps

ula

tio

n e

ffe

cie

nc

ies

(%

)

Lysozyme at starting concentration of 1mg/mL

Supercritical CO2 process Chemical pathway

0

1

2

3

4

5

6

7

8

HPLC Micrococcus lysodeikticus

Ly

so

zy

me

en

ca

ps

ula

tio

n lo

ad

ing

(%

)

Lysozyme at starting concentration of 1mg/mL

Supercritical CO2 process Chemical pathway

Lysozyme encapsulation in CaCO3 microparticles

Influence of the formulation process

Hassani et al.J.Mater.Chem.B , 2013, 1, 4011-4019

23

Page 24: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

Formation of CaCO3 microparticles

Influence of templating macromolecules

(collaboration CERM, Liège, Prof. C. Jérôme)

Co, H.; Antonietti, M. 1998, 382, 582–589. Ergul Yilmaz, Z.; Debuigne, A.; Calvignac, B.; Boury, F. ; Jérome C. (J.Mater. Chem. B, 2015, 3, 7227). 24

Page 25: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

Proposed mechanism for microparticle formation

and lysozyme encapsulation

Hassani et al., J. Mater. Chem. B, 2013, 1, 4011–4019

25

Page 26: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

SUMMARY

• What is a supercritical CO2 and its advantages

• The main issues in protein encapsulation

• ScCO2 as a W/C emulsion continuous phase and reactant – Protein encapsulation into PLGA microspheres

– Protein encapsulation into calcium carbonate microparticles

– Preliminary evaluation for application in tissue engineering (cartilage)

• Perspectives and conclusions

26

Page 27: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

27

Principles of tissue engineering

Page 28: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

0 % 0.2 % 1 % 2 %

5 % 10 % 0 %

0

1

2

3

4

5

6

7

HPMC-Si HPMC-Si CaCO3 2/ 0.01

HPMC-Si CaCO3 2/ 0.02

HPMC-Si CaCO3 2/ 0.04

HPMC-Si CaCO3 2/ 0.1

HPMC-Si CaCO3 2/ 0.2

Pa.s

Viscosity

0

5

10

15

20

25

30

35

40

HPMC-Si HPMC-Si CaCO3 2/ 0.01

HPMC-Si CaCO3 2/ 0.02

HPMC-Si CaCO3 2/ 0.04

HPMC-Si CaCO3 2/ 0.1

HPMC-Si CaCO3 2/ 0.2

Tim

e (m

in)

Gel point

A B

C D

Distribution of CaCO3 microspheres Inside the hydrogel (Coll. P. WEISS, LIOAD, Nantes)

28

Page 29: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

0

10

20

30

40

50

60

70

80

90

100

0 5 10 15 20 25 30

Accum

ula

tive

rele

ase

of

acti

ve lyso

zym

e (

%)

Time (days)

Si-H PMC/ CaCO3

Si-H PMC

Lysozyme release study from Si-HPMC hydrogel

and Si-HPMC/CaCO3 combined hydrogel

SEM images of Si-HPMC/CaCO3 2 wt % hybrid hydrogel at different time point during lysozyme release experiment.

Si-H PMC Si-H PMC/ 0.2 wt% CaCO3 Actinomycin-D

Si-H PMC/ 5 wt% CaCO3 Si-H PMC/ 4 wt% CaCO3 Si-H PMC/ 3 wt% CaCO3

Si-H PMC/ 2 wt% CaCO3 Si-H PMC/ 1 wt% CaCO3 Si-H PMC/ 0.5 wt% CaCO3

In vitro viability tests CLSM images of hASC cells seeded within pure Si-HPMC hydrogel and Si-HPMC/CaCO3 hydrogels

(Coll. P. WEISS, LIOAD, Nantes) 29

Page 30: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

A B

C D

E F

A) pure Si-HPMC hydrogels, B) Si-HPMC hydrogels combined to chondrocytes, C) Si-HPMC/ 1 wt%CaCO3 hydrogels combined to hNC cells, D) Si-HPMC/ 2 wt%CaCO3 hydrogels combined to hNC cells, E) Si-HPMC/ 1 wt%CaCO3 hydrogels combined to hASC cells, F) D) Si-HPMC/ 2 wt%CaCO3 hydrogels combined to hASC cells.

Histological analysis after in vivo implantation (Coll.

P. WEISS, LIOAD, Nantes)

30

Page 31: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

TGFb1 release study : Si-HPMC/PLGA MP

31

Page 32: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

SUMMARY

• What is a supercritical CO2 and its advantages

• The main issues in protein encapsulation

• ScCO2 as a W/C emulsion continuous phase and reactant – Protein encapsulation into PLGA microspheres

– Protein encapsulation into calcium carbonate microparticles

– Preliminary evaluation for application in tissue engineering (cartilage)

• Perspectives and conclusions

32

Page 33: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

Reduce/control the particle size

Increase the emulsion stability

Reduce particle agregation

Synthesis and use of specific surfactants for

emulsification in scCO2

Cédric Boyère et al., Carbohydr. Res. 2011, 346, 2121-2125

Center for Education and Research on Macromolecules

33

Page 34: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

Amaranth dye

Assessment of the capacity of Man-C2F8 4 (C = 90,3 mM) to stabilize (water+amarante)/scCO2 (1:9 v/v ) emulsion at high pressure and 45°C.

High Pressure Homogenizer

150 bar, homogenization 15 min 250 bar, homogenization 15 min

homogenization stop homogenization t = 0 overnight

150 bar

without homogenization

34 A. Favrelle, C. Boyère et al., J. Colloid Interface Sci., 398, 2013, 273-275

CO2 phase

aqueous layer

stainless steel flat bottom

Synthesis and use of fluorinated surfactants for

emulsification in scCO2

Page 35: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

Drop (3µL) at t = 0 and distorted by the surfactant

Pendant Drop Tensiometer

c = gρ ∕ ϒ

Tewes et al., J. Phys. Chem. B, 2004

1 d _ ___ x dx

(x sin ф) = 2 S _ _ cz

35

Pure water

With surfactant 4 (10-4M)

conditions : 80 bar, 40°C

A. Favrelle, C. Boyère et al., J. Colloid Interface Sci., 398, 2013, 273-275

Tensiometry at the water/scCO2 interface

Page 36: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

Conclusions

• SCF technologies is a tool box:

– For protein encapsulation avoiding toxic solvent

• polymeric particles

• mineral particles

– To process preforming polymers

• Foaming, polyHIPES

• Impregnation of actives substances

– Developing scaffolds and new materials

– To scale-up and produce GMP batches

36

Page 37: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

• BUT it needs further development to improve:

– The knowledge of processes

– In situ characterization

– The development of GRAS additives adapted to this tunable medium

– To convince the pharmaceutical companies of the interest of “green chemistry”

– To overcome industrial bottleneck

37

Conclusions

Page 38: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

Z. Ergül

Dr. T.Beuvier Pr. A. Gibaud

M.K. Tran& Amin Swed

BIOREGOS PROJECT

Research Institute in Health care engineering of Angers

MINT INSERM U1066

University of Angers, France L. Hassani

Aknowlegments

LPEC Laboratory

University of Maine, France

Pr. C. Jérôme Pr. A. Debuigne A. Farvelle C. Boyère

B. Ramalapa

T. Cordonnier F. Hindré B. Calvignac

P. Weiss J. Guicheux G. Rethore C. Boyer LIOAD INSERM U791, University of Nantes, France 38

Page 39: Protein Encapsulation using Pressurized CO based Processes ...as a W/C emulsion continuous phase and reactant –Protein encapsulation into PLGA microspheres –Protein encapsulation

Thank you for your attention

SCIAM (“Service Commun d'Imagerie et d'Analyse Microscopique”) for electron microscope images. “Région Pays de la Loire”(Bioregos 2 project), ANR (“Agence Nationale pour la Recherche”, grant (ANR-09-PIRI-0004-01)

EACEA (EC)

39