Metal nanoparticles: The protective nanoshield against virus infection

Abstract

Re-emergence of resistance in different pathogens including viruses are the major cause of human disease and death, which is posing a serious challenge to the medical, pharmaceutical and biotechnological sectors. Though many efforts have been made to develop drug and vaccines against re-emerging viruses, researchers are continuously engaged in the development of novel, cheap and broad-spectrum antiviral agents, not only to fight against viruses but also to act as a protective shield against pathogens attack. Current advancement in nanotechnology provides a novel platform for the development of potential and effective agents by modifying the materials at nanolevel with remarkable physicochemical properties, high surface area to volume ratio and increased reactivity. Among metal nanoparticles, silver nanoparticles have strong antibacterial, antifungal and antiviral potential to boost the host immunity against pathogen attack. Nevertheless, the interaction of silver nanoparticles with viruses is a largely unexplored field. The present review discusses antiviral activity of the metal nanoparticles, especially the mechanism of action of silver nanoparticles, against different viruses such HSV, HIV, HBV, MPV, RSV, etc. It is also focused on how silver nanoparticles can be used in therapeutics by considering their cytotoxic level, to avoid human and environmental risks.

Silver Nanoparticles as Potential Antibacterial Agents

“…Silver has always been used against various diseases; in the past it found use as an antiseptic and antimicrobial against Gram-positive and Gram-negative bacteria [14][15][16] due to its low cytotoxicity [17]. AgNPs were considered, in recent years, particularly attractive for the production of a new class of antimicrobials [4,[18][19][20][21][22][23][24][25] opening up a completely new way to combat a wide range of bacterial pathogens. Although the highly antibacterial effect of AgNPs has been widely described, their mechanism of action is yet to be fully elucidated.…”

Nanoparticle-Mediated Delivery of Therapeutic Drugs

“…Metal nanoparticles have been also studied for their antiviral efficacy. Metal-based nanoparticles inhibit viral replication or prevent the entry of virus inside the host cell [25]. It has been demonstrated by Lara et al [29] that silver nanoparticles inhibit HIV-1 by interacting with the CD4 binding domain of the gp120 glycoprotein receptor present on the envelope of HIV-1 virus and prevents interaction between the glycoprotein envelope and target cell membrane receptors, thus, effectively inhibiting viral fusion and infectivity [29].…”

“…Silver nanoparticles have been extensively studied for their toxic effects on different microorganisms, including Gram-negative and Gram-positive bacteria, fungi and virus [23][24][25]. The antibacterial activity of metal-based nanoparticles has been mainly attributed to the pore-forming ability of nanoparticles in bacterial membranes, resulting in increased membrane permeability of the bacterial cells and subsequent cell death [26].…”

Advances in Biogenic Nanoparticles and the Mechanisms of antimicrobial Effects

“…Although antioxidant defence of the cell (glutathione/glutathione disulfide GSH/GSSG ratio) guards the cells to some extent from ROS, excess ROS production may produce oxidative stress [8] and can assault membrane lipids, consequently, leads to impairment of membrane and mitochondrial dysfunction and DNA damage [90] . Metals can act as catalysts and generate ROS in the presence of dissolved oxygen [91] . Therefore, AgNPs may catalyse the reaction with oxygen directing to release excess free radicals.…”