Biodegradable polymer micelles as drug carriers and control drug release technique by assembled micelles

This paper prepared some kinds of PEGlytated biodegradable copolymer by condensation and radical polymerization methods, which are respectively methoxy poly(ethylene glycol) - b-poly(D,L-lactic acid) diblock copolymer (PEDLLA) and Methoxy poly(ethylene glycol) - b-poly(L-lactic acid) diblock copolymer(PELLA), PEG-b-polycaprolactone-b-PEG triblock copolymer(PECL),PEG grafted poly(ethylene-cyanoacrylate)(PECA),PEG-b-poly(adipic anhydride) copolymer (PEAA), Poly(ethylene glycol) grafted chitosan(PECS)?These block or graft copolymers can self-assemble into nano-micelles, which present excellent properties as hydrophobic drug or biomedcine carriers. This paper prepared hydrophobic drug loaded micelles by solid melting dispersion method, self-emulsification/solvent evaporation method and dialysis technique. The insulin nanoparticles were made by multi-emulsification method. The study results indicated that these drug loaded micelles or nanoparticles were stable, small sized with narrow particle size distribution, and had high drug entrapment efficiency. A kind of effective and convenient technique for controlling drug release by assembled micelles using different kinds of amphiphilic copolymers was developed. The results of the transdermal drug release of drug loaded polymer micelles through mouse skin indicated that PEDLLA assembly micelles can went through the mouse skin with drug at a whole micelle, which can carry drug through the skin and release the drug.