Facile synthesis of Au@PNIPAM-b-PPy nanocomposites with thermosensitive and photothermal effects

In this article, we reported a facile method to in-situ synthesize Au@PNIPAM-b-PPy nanocomposites with thermosensitive and photothermal effects using amphiphilic poly(N-isopropylacrylamide)-block-poly(pyrrolylmethylstyrene) (PNIPAM-b-PPMS) diblock copolymers as ligands. The hydrophobic PPMS block can in-situ reduce AuCl^-₄ to zero-valent gold and simultaneously be oxidatively copolymerized with the free pyrrole monomers to form a crosslinked and conjugated polypyrrole (PPy) layer. The hydrophilic PNIPAM block as a stabilizer can produce highly thermosensitive effect. Moreover, the resultant Au@PNIPAM-b-PPy nanomaterials show a strong absorption in the near infrared (NIR) region, which endowed the system excellent photothermal effect. On the basis of the PPy photothermal and PNIPAM thermosensitive effects, the above Au@PNIPAM-b-PPy nanomaterials show a reversible, soluble-precipitate transition upon the NIR irradiation off-on.