Facts about the antimicrobial properties of silver

Silver in history

For thousands of years, silver has been known for its antimicrobial activity. The ancient Romans treated their water with silver coins to maintain its purity. In medicine, silver has played an important role since the 19th century when silver nitrate solution was dripped into the eyes of newborn infants as a prophylactic treatment for bacterial infections often causing blindness. Silver sulfadiazine cream has been used in hospitals for decades as a standard highly effective treatment to prevent infection of burn wounds.

Antimicrobial effect against bacteria and other microbes

While silver metal is historically recognized as being antimicrobial, it is not the pure silver that is active, but the liberated silver ions. The effect of silver ions stems from 3 key mechanisms:

1. Binding and damage to the bacterial cell surface.
2. Inhibition of respiration by suppressing transport of vital Ca²⁺ and Zn²⁺ ions across the cell membrane.
3. Binding strongly to electron donor groups on constituent bacterial molecules containing sulphur, oxygen, or nitrogen.