Preparation of pNIPAM modified gold nanorods and their delivery.

T. Niidome A. Shiotani
T. Mori and Y. Katayama
Faculty of Engineering, Kyushu University, Fukuoka 819-0395, Japan
Center for Future Chemistry, Kyushu University, Fukuoka 819-0395, Japan
PRESTO, Japan Science and Technology Agency, Kawagushi 332-0012, Japan

Thermosensitive polymer gel-coated gold nanorods were prepared by precipitation polymerization of NIPAM and co-monomer (DMAA or AAm) that was added to tune phase transition temperature above body temperature. PNIPAM-DMAA and PNIPAM-AAm-coated gold nanorods showed phase transition temperature at 38ºC and 41ºC, respectively. After intravenous injection of the gel modified gold nanorods and irradiation of near infrared laser to a tumor, the larger amount of gold was detected in the irradiated tumor than in the non-irradiated tumor. It would be due to the hydrophobic interaction between cellular membrane or extracellular matrix and gel surfaces induced by the photothermal effect of gold nanorods.