Chitosan gel incorporated peptide-modified AuNPs for sustained drug delivery with smart pH responsiveness

In this study, gold nanoparticles (AuNPs) were modified with a negatively charged peptide, Fmoc-GCE, for use as nanocarriers of a positively charged anti-tumor drug, doxorubicin hydrochloride (DOX). The Fmoc-GCE-modified AuNPs were further used to load DOX through electrostatic interaction. A temperature-sensitive gel, chitosan (CS) gel, was chosen to act as an appropriate platform to incorporate the modified AuNPs as a drug carrier. The incorporation of AuNPs makes the complex gel exhibit SERS characteristic, showing application prospects for the detection of cancer. More importantly, this drug delivery system with rather good biocompatibility can significantly extend the release time of the incorporated drugs and possesses pH responsiveness, exhibiting the advantages of controlled release and reduced side effects.