Bio-distribution and toxicity of noble metal nanoparticles in humans

Abstract

Nanotechnology is attracting the interest of scientists since the last few decades and is the technology of twenty-first century. It deals with the materials having at least one dimension in the range of nanometre scale. There is developing enthusiasm towards the application of nanotechnology in diverse fields. Carbon nanotubes, dendrimers, quantum dots and metal nanoparticles are mostly preferred for applications in various fields. Among them metal nanoparticles, especially the noble metallic nanoparticles, are of great importance due to their ease of synthesis, characterization, surface functionalization and size- and shape-dependent unique optoelectronic properties. They include silver, gold, platinum, palladium and rhodium nanoparticles. But with their increased use and likelihood of potential exposure, the concerns over their potential risk are also rising. Many studies have highlighted the toxicological considerations of those nanoparticles. The present chapter showcases some of the key studies on the in vitro toxicity of noble metal nanoparticles by using human cell lines. It is general observation that toxicity of noble nanoparticles occurs due to exposure mainly via three routes, i.e. through injection or damaged skin, ingestion with food so as to reach gastrointestinal tract and inhalation causing accumulation in the respiratory tract. Hence, in vitro systems representing each of these exposure routes are generally exploited for finding the risk. Here, we discuss several critical investigations exploring the nanoparticle- wise toxicity. The goal is to explore the current knowledge about the potential risk of noble nanoparticles while drawing the general cytosolic and molecular mechanism lying behind the induction of harmful effects on various cell models.