2014 Volume 14 Issue 1 Pages 17-21
Gold nanorods have absorption bands in the near-infrared region. The absorbed light energy is converted into heat by gold nanorods. Therefore, drug delivery systems that can be controlled by the heat produced by near-infrared light irradiation will be constructed. First, we modified gold nanorods with double-stranded DNA. That is, release of single stranded DNA is induced by the produced heat from the gold nanorods. We also constructed a controlled release system of PEG chain mediated by retro Diels-Alder reaction induced by the photothermal effect. Next, we designed transdermal protein delivery system enhanced by the photothermal effect. We first casted gold nanorods, acting as a heating device in response to near-infrared light irradiation, onto the skin surface. After applying an aqueous solution of ovalbumin to the skin, the skin was irradiated by near-infrared laser light. The irradiation increased the skin temperature resulting in an efficient translocation of ovalbumin into the skin. Thus, the controlled-release systems and enhanced transdermal protein delivery system triggered by near-infrared light irradiation will be further expanded to development of functional drug delivery system.
