Chapter 6: Mechanism of Silver and Gold Nanoparticles Against Infectious Disease-causing Pathogens

Infections are caused by the growth or invasion of pathogenic microorganisms in the human body and infectious diseases, also called as communicable diseases, are a major burden to human health worldwide. Pathogens have developed resistance through various mechanisms, such as increasing the amount of time they stay in the intracellular environment, in which drugs are unable to reach therapeutic levels. Furthermore, there are a few issues that decrease the efficacy of drugs, including the use of high doses and frequent drug administrations that might have harmful side effects or can be toxic. Such issues can be resolved and therapeutic effectiveness can be improved with the use of nanoparticle systems. The mechanism of action provides knowledge about the pathway by which nanoparticles act on infectious pathogens. This, in turn, provides clarity about how the nanoparticles act against a particular group of pathogenic microbes in a more specific way. Numerous microorganisms, such as bacteria, fungi, and viruses, have been investigated with respect to the antimicrobial activity of nanoparticles. This chapter summarizes the effects of silver and gold nanoparticles against microbial infections along with the possible mechanism of action.