Influence of the anodization process conditions and the microstructure on the photothermal effect of porous silicon used as a therapeutic agent in cancer thermotherapy

Recently it has been reported that porous silicon (PSi) can be used as a therapeutic agent for cancer thermotherapy based on near-infrared (NIR) light irradiation. It is more important than anything else to develop a nanomaterial thermal coupling agent with a high photothermal effect in order to secure irreversible destruction of cancer cells and high selectivity between tumor tissues and healthy tissues in thermotherapy. In this paper we report the influence of anodization process parameters or the microstructure of PSi on the photothermal effect of PSi during NIR light irradiation. As the HF concentration, current density and etching time in the anodization process for PSi synthesis increases, the photothermal effect is enhanced since the pore size or the nanocrystallite size of the PSi decreases and the porosity of the PSi increases. The influence of quantum size effect on the photothermal effect in PSi is also discussed.