Antimicrobial activity and toxicity of gold nanoparticles: research progress, challenges and prospects

Gold nanoparticles are emerging materials that exhibit characteristics distinct from those of traditional materials and that have promising potential for application in the fields of chemistry, physics, biology and medicine. During the past decades, numerous studies on the antimicrobial activity and toxicity of gold nanoparticles have been published. With respect to antimicrobial activity, gold nanoparticles conjugated with small molecules, such as antibiotics, drugs, vaccines and antibodies, are more efficient than individual nanoparticles and molecules. Regarding the toxicity effects, results are often unclear and conflicting because of the lack of a standard experimental method; various studies have used different approaches, administration routes and doses, and similar experiments may lead to different conclusions. To provide a systematic overview of and insight in the current knowledge for researchers committed to this filed, we discuss the recent research advances related to the antimicrobial activity and toxicity of gold nanoparticles, both in vitro and in vivo, and identify major issues that require further study.