Release Model and Characteristics of Biodegradable Implantable Drug Delivery System with Micro-porous Structure

摘要

To eliminate the release-delayed phenomenon of macromolecular drug delivery system at the early release stage,biodegradable implantable drug delivery system with micro-porous structure was designed by Bio-MEMS technology in this paper.Polylactic acid -polyglycolic acid (PLGA) material was chosen to prepare drug matrix.Drug release model was built by mass transfer equation and the finite element method (FEM) in the case of time-varying diffusion coefficient of drug in PLGA.Influencing factors of the cumulative amount of release drug were analyzed.And the results suggest that the PLGA monomer ratio is one of the major influencing factors of the drug release time.Better linearity of cumulative amount of release drug could be achieved by reducing the micro-porous diameter and package layer thickness.The drug delivery system with micro-porous structure nearly has no release-delay phenomenon at the early stage of release and maintains a good linearity in the whole release process.The simulation results have certain significance for the optimal design of drug delivery system with micro-porous structure.