Factors affecting the degradation and drug‐release mechanism of poly(lactic acid) and poly[(lactic acid)‐<i>co</i>‐(glycolic acid)]

TLDR

Polymer degradation rates are influenced by pH, copolymer composition, hydrophilicity, crystallinity, molecular weight, device size, and other factors, though literature shows conflicting evidence regarding reactive additives and degradation pathways. The paper reviews key factors influencing degradation and drug‑release rates of bio‑erodible polymers to improve control in biomedical applications. The review organizes these factors by decreasing importance, examining intrinsic polymer properties and processing parameters that affect degradation and drug release. © 2004 Society of Chemical Industry.

Abstract

Abstract This paper reviews the most important factors affecting the degradation and drug‐release rate of bio‐erodible polymers for better control in biomedical applications. There are several factors that influence the overall rate of degradation, in addition to pH and copolymer composition. In general, polymer degradation is accelerated by greater hydrophilicity in the backbone or end groups, lesser crystallinity, lower average molecular weight, and smaller size of the finished device. At the moment, literature reflects contradictions about the role played by chemically reactive additives, crystallinity and degradation path. Factors affecting degradation and drug‐release rate are discussed in their decreasing order of importance, including intrinsic properties of polymers and processing parameters. Copyright © 2004 Society of Chemical Industry