An overview on nanoparticles used in biomedicine and their cytotoxicity

Abstract Nanotechnology is the development of engineered nanoparticles to use in biomedical applications. Nanoparticles have unique physicochemical properties for use in biomedicine, however, their cytotoxicity has demonstrated in some situations that have caused concern about their clinical application. Nanoparticles must be non-toxic and biocompatible in order to be successful in biomedical applications. Nanoparticles can easily enter the body due to their small size and reach very sensitive organs through different routes. Cytotoxicity of nanoparticles is dependent on various parameters such as size, shape, charge of surface, chemistry, and surface modifications. There are several in vitro cytotoxicity assays for nanoparticle cytotoxicity assessment that is discussed briefly in this review. The generation of reactive oxygen species due to the higher surface area to volume ratio of nanoparticles is the main mechanism responsible for their cytotoxicity that can result in oxidative stress and consequent damage to cell functions and cell death. This review discusses a number of commonly used nanoparticles in biomedical, including carbon-based nanoparticles, metallic nanoparticles, and quantum dots, and their possible cytotoxicity mechanisms.