Synthesis of biodegradable/biocompatible block copolymers for obtaining polymeric micro-and nanoparticles for controlled drug release

Abstract

Taking into account the growing interest in the association stimuli responsive and biocompatibility of some polymers with the biodegrability of others, to the development of controlled drug release systems, this project aims the elaboration of block copolymers constituted of poly (3-hydroxybutyrate-co-3-hydroxyvalerate)-b-poly (N-vinylcaprolactam) (PHBHV-b-PNVCL) and poly (µ-caprolactone)-b-poly (N-vinylcaprolactam) (PCL-b-PNVCL ), in which one is biodegradable (PHBHV e PCL) and the other is biocompatible and a temperature responsive (PNVCL). Those copolymers are synthesized, firstly, by esterification reactions between hydroxil termination from PHBHV and PCL blocks with the carboxil termination from NVCL homopolymers. After this, the RAFT mechanism of controlled polymerization Will be tested. To achieve this, chain transfer agent will be synthesized and used to functionalize PHBHV and PCL blocks and produce a second block of PNVCL. Finally, cicloadition 1,3 dipolar reactions between azides and alkynes ("Click Chemistry") will be studied as third technique for obtention of block copolymers. The copolymers will be used to prepare nanoparticles, containing an active principle (Paclitaxel) through emusion-diffusion/solvent evaporation tecnic. The citotoxicity of block copolymer and the active agent in vitro release will be evaluated. (AU)