One-pot synthesis of pH-responsive PEGylated nanogels containing gold nanoparticles by autoreduction of chloroaurate ions within nanoreactors

One-pot synthesis of pH-responsive PEGylated nanogels (diameter < 100 nm) containing gold nanoparticles (AuNPs) was successfully carried out through the autoreduction of HAuC14 with PEGylated nanogels constructed from cross-linked poly[2-(NN-diethylamino) ethyl methacrylate] (PDEAA/IA) core and tethered PEG chains. Transmission electron microscopy image of the nanogel containing AuNPs prepared at N/Au ratio = 8 revealed that the average number of AuNPs in a single nanogel and average diameter of the AuNPs were about 10 particles/nanogel and 6 nm, respectively. The surface plasmon band of the PEGylated nanogel containing AuNPs was shifted in response to pH, indicating that the cross-linked PDEAMA core of the nanogels acts as not only nanoreactor but also pH-sensitive matrix.