Hydrolytic Degradation of Poly DL-(Lactide)

Poly (DL-lactide) or poly (DL-lactic acid) (PLA), has been proposed as a component of several controlled-release drug forms because it degrades in living tissue to harmless products (1,2). Thus, devices or particles made of this material could be slowly metabolized and thus leave the body harmlessly after the drug is released. The solubility of PLA in many organic solvents (ketones, esters, aromatics, and chlorinated aliphatics) gives considerable flexibility in device fabrication. PLA has been proposed for use as fibers (3), microcapsules (4), and larger implants (2). Experimenters have made a variety of drug forms and devices to deliver drugs ranging from birth-control agents and narcotic antagonists, to anticoagulants and depressants.