Chemical and Physical Structure of Polymers as Carriers for Controlled Release of Bioactive Agents: A Review

Abstract

In a controlled release system a drug, pesticide, or other bio-active agent is incorporated into a carrier, generally a polymeric material. The rate of release of the substance is determined by the properties of the polymer itself and is only weakly dependent on environmental factors (such as the pH of bodily fluids). Controlled release systems are capable of delivering substances slowly and continuously for up to several years.