Analysis of particle size, polydispersity and polymer degradation on progesterone delivery from PLGA-based microparticles: Experimental and mathematical modelling

I.M. HELBLING; C. BUSATTO; DR. JULIO A. LUNA; D. ESTENOZ

Congreso; Analysis of particle size, polydispersity and polymer degradation on progesterone delivery from PLGA-based microparticles: Experimental and mathematical modelling; 2018

Progesterone (PG) is a lipophilic steroid hormone with low molecular weight. Several PG delivery systems based on biodegradable and non-biodegradable polymeric matrices have been used for estroussynchronization in cattle [1]. Poly(lactic-co-glycolic acid) (PLGA) has been widely studied as biomaterial for drug delivery applications [2]. Biodegradable microparticles are of special interest because they presentseveral advantages, such as easy preparation and administration, do not require surgical intervention to remove the material and it is possible to control the release and degradation rates on the basis of thephysicochemical properties of the polymer. In this study, PLGA microparticles for PG delivery were prepared by the solvent extraction/evaporation and microfluidic techniques. Microparticles were characterizedto determine size distribution, morphology, encapsulation efficiency and thermal properties. The effect of particle size, polydispersity and polymer degradation on the in vitro release of PG was studied. Biphasicand triphasic release profiles were observed for smaller and larger microparticles, respectively. A mathematical model for the prediction of PG release from PLGA microspheres was developed. Our previousmodel for the heterogeneous hydrolytic degradation of PLGA microspheres [3] was extended in order to incorporate the drug dissolution and diffusion in the polymeric matrix. The model was adjusted andvalidated with the experimental data. Simulation results are in very good agreement with experimental results [4].