Biodegradable polymersomes for controlled drug release

Abstract

Hydrophilic fluorescein isothiocyanate-dextran (FD, mol. weight 4000 g/mol) could be readily incorporated in polymersomes (PS) made of different amphiphilic biodegradable block copolymers based on PEG-PDLLA, PEG-PCL, and PEG-PTMC. The FD release from these polymersomes in PBS at 37 °C was complete within approximately 10 days. Both the length of the hydrophobic block as well as the type of the hydrophobic block have a major influence on the release rate of FD from the PS, while the hydrophilic block length has only a minor influence on the release rate. For all systems the release of FD follows first order kinetics, confirming that the FD containing polymersome system is a membrane controlled reservoir system.