Role of Silver Ions in Destabilization of Intermolecular Adhesion Forces Measured by Atomic Force Microscopy in Staphylococcus epidermidis Biofilms
In this study published in the journal Antimicrobial Agents and Chemotherapy (Dec. 2005, American Society for Microbiology) it was revealed that Staphylococci epidermis biofilms have been found to be “markedly impaired” by very low, non-inhibitory levels of silver ions. This is important news, since biofilms give communities of microorganisms a distinct ability to resist antibiotic drugs.
If low levels of silver ions can impair biofilms, then its use may well help resolve one factor in the growing problem of antibiotic-resistant microorganisms. According to the study authors, “Our AFM studies on the intermolecular forces within the EPSs of S. epidermidis RP62A and S. epidermidis 1457 biofilms suggest that the silver ions can destabilize the biofilm matrix by binding to electron donor groups of the biological molecules. This leads to reductions in the number of binding sites for hydrogen bonds and electrostatic and hydrophobic interactions and, hence, the destabilization of the biofilm structure… After the addition of silver ions and within 60 min of contact, the overall structure of the biofilm became partially destroyed and the inner structure of biofilm was exposed. There were also significant amounts of EPSs around the damaged biofilm colony, confirming the effect of silver ions on the grown biofilm matrix.”