Silicon nanocrystals: physical properties and potential biomedical applications

Abstract

Silicon (Si) nanocrystals (NCs) possess photoluminescence at room temperature and promising properties
for biomedical applications as bioimaging and various therapeutic modalities. The photodynamic therapy
application is based on an ability of Si-NCs to sensitize the generation of reactive oxygen species under
illumination. The sonodynamic therapy with Si-NCs can be realized due to their properties to activate the
cavitation followed by destruction of cancer cells and tumors. Furthermore, Si-NCs in aqueous media
under electromagnetic radiofrequency irradiation can activate the heat release that is promising for the
hyperthermia treatment of cancer. This paper reviews the physical properties of Si NCs, which are
essential for their applications both in medical diagnostics and therapy. In the paper the properties of Si-
NCs and nanoparticles (NPs) are analyzed to reveal their potential for biomedical applications. Besides
the data on physical properties of Si-NCs and NPs the results of biomedical investigations of these
nanomaterials are also discussed.