Comparative Mathematical Modeling of Biphasic Drug Release from Matrix and Core–Shell PLGA Nanoparticles

Poly(lactic-co-glycolic acid) (PLGA) nanoparticles are good drug delivery vehicles, but particle architecture and transport properties are important factors that dictate the release behavior.This study formulates a mathematical model based simulation that can be used to compare biphasic drug release in matrix and core-shell PLGA nanoparticles.The model is derived with six governing equations, including the spherical diffusion equation, first order PLGA degradation, degradation dependent effective diffusivity, initial burst release and cumulative release equations.Under all conditions (C1-C5), the release of matrix nanoparticles at the end of Day-30 rose from 64.9% to 96.8%, while the release of core-shell nanoparticles improved from 49.1% to 92.3%.The matrix was reduced from 17.1 to 3.2 days, while the core-shellwas reduced from over 30 days to 4.7 days.Positive sensitivity (release) was observed for the parameters diffusion coefficient (0.63/0.55) and degradation rate ( 0.48/ 0.44) while parameters particle radius (-0.42/-0.36) and shell thickness (-0.18/-0.57) decreased release.The results show that there are differences in the biphasic drug release profiles derived from different architectures simulated.