Silicon nanoparticles produced by femtosecond laser ablation in water as novel contamination-free photosensitizers

Abstract

We report the synthesis of novel inorganic contamination-free photosensitizers based on colloidal silicon nanoparticles prepared by laser ablation in pure deionized water. We show that such nanoparticles are capable of generating singlet oxygen (1O2) under laser irradiation with a yield estimated at 10% of that of photofrin, which makes them a potential candidate for therapeutics, antiseptics, or disinfectants. We also discuss a model of 1O2 generation and the possibility for optimizing its release. Potential advantages of such novel inorganic photosensitizers include stable and nonphotobleaching 1O2 release, easy removal, and low dark toxicity. © 2009 Society of Photo-Optical Instrumentation Engineers.