Body temperature polymerization and in situ drug encapsulation in supercritical carbon dioxide

Body-temperature and solvent-free polymerization and in situ fabrication of drug-loaded microparticles are reported for the first time. The key point is to simplify the cumbersome processes and avoid the harsh conditions in the traditional fabrication of biodegradable medical microparticles, reducing the energy consumption and fabricating cleaner biodegradable formulations with controlled size and drug release profiles. We have designed a surfactant P(CL–GA)–PFPE–P(CL–GA) which efficiently promotes the formation of narrowly distributed microparticles of minimum 5 μm at body temperature. The following drug loading investigation confirmed that PTX evenly distributes in the PPDO microparticles in amorphous state, giving a controlled release profile with the cumulative releasing rate reaching 50% in one month. Most importantly, all the processes are conducted at body temperature in one-pot, presenting promising possibilities of both energy and cost conservation.