Synthesis of Bioerodible Poly(ε-caprolactone) Latexes and Poly(D, L-lactide) Microspheres by Ring-Opening Polymerization

Abstract

Poly(ε-caprolactone) [poly(CL)] latexes and poly(D,L-lactide) [poly(D,L-Lc)] microspheres were prepared directly by ring-opening precipita tion polymerization carried out in heptane-dioxane (4:1 v/v) mixed solvent in the presence of poly(dodecyl acrylate)-g-poly(ε-caprolactone) used as the surface active agent. This designed synthetic method yielded latexes and microspheres with narrow size distribution; poly(CL) latex D v /D n = 1.038 and for poly(D,L- Lc) microspheres D v /D n = 1.15. (D v and D n denote the volume and number average diameters of particles.) The poly(CL) latex, synthesized by using CH 3 CH 2 OAl(CH 2 CH 3 ) 2 as initiator, had a narrow polymer polydispersity of 1.11. Poly(D,L-Lc) microspheres, besides polymer with M w /M n = 1.05 contained some unreacted lactide. Adsorption of human serum albumin and human gamma globulins on both kinds of polyester particles was studied for their potential use as polypeptide and protein delivery systems.