Disulfide core cross-linked PEGylated polypeptide nanogel prepared by a one-step ring opening copolymerization of N-carboxyanhydrides for drug delivery.

A novel disulfide core cross-linked PEGylated polypeptide nanogel has been synthesized by a one-step ring opening copolymerization of γ-benzyl L-glutamate N-carboxyanhydride and L-cystine N-carboxyanhydride using an amino group-terminated poly(ethylene glycol) methyl ether as initiator. Characterization of products confirms the formation of a core cross-linked PEGylated nanogel with disulfide linkages with a size of about 250 nm, and these studies also confirm that this nanogel can easily be broken by glutathione. Cell viability experiments show the good biocompatibility of the as-prepared polymer. Studies relating to loading and controlled release of indomethacin under reduction-sensitive conditions reveal that the nanogel is a good candidate for drug delivery systems.