A NOVEL PREPARATION METHOD FOR POLYMERIC MICROPARTICLES WITHOUT THE USE OF ORGANIC-SOLVENTS

Microparticles (microcapsules and microspheres) of different chemical compositions (methacrylated dextran, methacrylated poly(ethyleneglycol ) and gelatin) were prepared using a novel emulsion technique based on polymer-polymer immiscibility in aqueous solutions. The effect of pol ymer chemical composition and crosslink density on the properties of t he microspheres was evaluated. Microparticles with a volume mean diame ter ranging from 2.5 to 25 mu m could be prepared in a reproducible wa y. Scanning electron microscopy revealed that non-porous and spherical particles were obtained for all preparations. Microcapsules with a si ngle core were prepared using a double emulsion technology, based on t he same principle of polymer-polymer immiscibility. These results demo nstrate that this new emulsion technique without organic solvents can be used for the preparation of well-defined microparticles differing i n size, morphology and chemical composition. (C) 1993 Elsevier Science E.V. All rights reserved.