Biocompatibility, biodegradation and biomedical applications of poly(lactic acid)/poly(lactic-co-glycolic acid) micro and nanoparticles

Poly(lactic acid) (PLA) and poly(lactic-co-glycolic acid) (PLGA) are among the well-documented FDA-approved polymers used for the preparation of safe and effective vaccine, drug and gene delivery systems using well-described reproducible methods of fabrication. Various nano and microparticulates are fabricated using these polymers. Their successful performance relies on PLA and PLGA biocompatibility and degradability characteristics. This review provides an overview of the biocompatibility and biodegradation of PLA, PLGA and their copolymers, with a special emphasis on tissue responses for these polymers as well as their degradation pathways and drug release models. Moreover, the potential of PLA and PLGA based nano and microparticulates in various advanced biomedical applications is highlighted. PLA and PLGA based delivery systems show promises of releasing different drugs, proteins and nucleic acids in a stable and controlled manner and greatly ameliorating their therapeutic efficacy. In addition, advancement in surface modification and targeting of nanoparticles has extended the scope of their utility.