Mechanism of action:
Gram-positive bacteria have a thicker cell wall(~30-~100 nm thick) than gram-negative bacteria (a few nanometers).
- The silver nanoparticles, stick to the surface of the gram-positive bacteria
- Silver ions (Ag+) are released by silver nanoparticles
- Silver ions denature ribosomes and inhibit protein synthesis
- The generation of reactive oxidation species (ROS) leads to lipid peroxidation, which disrupts the membranes of cell organelles.
- Nanoparticles enter the cell and cause adverse effects like inhibition of DNA replication, disruption of signal transduction, etc.
- Cell death
Reference:
Mikhailova EO. Silver Nanoparticles: Mechanism of Action and Probable Bio-Application. J Funct Biomater. 2020 Nov 26;11(4):84. doi: 10.3390/jfb11040084. PMID: 33255874; PMCID: PMC7711612.
Anjum, S., Jacob, G. & Gupta, B. Investigation of the herbal synthesis of silver nanoparticles using Cinnamon zeylanicum extract. emergent mater. 2, 113–122 (2019). https://doi.org/10.1007/s42247-019-00023-x