Disulfide cross-linked polypeptide nanogel conjugated with a fluorescent probe as a potential image-guided drug-delivery agent

摘要

A disulfide cross-linked PEGylated polypeptide nanogel with a near infrared fluorescence (NIRF) group has been synthesized. At first, a NIRF nanogel precursor is prepared by a ring-opening polymerization of L-cystine-N-carboxy anhydride with azide-functionalized poly(ethylene glycol) methyl ether. Alkyne cyanine is then conjugated to the nanogel by a click chemical reaction. The formation of the targeted nanogel is confirmed by a series of characterizations. The anticancer drug doxorubicin can be loaded into the NIRF nanogel by physical encapsulation, and the obtained drug-loaded NIRF nanoparticle shows reduction-promoted drug-release behavior in the presence of 10 mM glutathione. The as-prepared drug-loaded NIRF nanoparticle has potential applications in the real-time imaging of drug delivery in vivo.