Abstract
Aim: To investigate the effect of manipulation of the electrochemical environment around metallic implants on bacterial biofilm formation.
Background: The inability to prevent and treat prosthetic bacterial infection is a significant orthopaedic problem. Current antimicrobials are ineffective against bacterial biofilm communities. It is hypothesised that the alteration of the micro-environment could inhibit bacterial adhesion sufficiently to prevent biofilm formation allowing normal tissue integration to occur. Previous work by this group using zinc caused increased bacterial biofilm formation. Platinum being at the opposite end of the galvanic spectrum should cause the opposite effect.
Materials and Methods: Titanium 2mm Kirschner (K) wires (N=14) and Stainless Steel K wires (N=14) were cut into 50mm segments and sterilised. These were inoculated with either Staphylococcus Epidermitis (NC011047) or Staphylococcus Aureus (NC012973) suspensions. Superficial, non-adherent bacteria were removed by serial rinsing in phosphate buffered solution (PBS).
The K wires were added to either the culture media alone or the culture media containing platinum and incubated at 37 degrees for 24 hours. The wires were then removed from the media and rinsed in PBS. Samples were subjected to sonication, to fragment biofilms thereby releasing the bacteria, which were then quantified by serial log dilution technique and manual counting.
The presence of platinum reduced the adhesion of both Staph Aureus and Staph Epidermidis to stainless steel. This reduction was statistically significant using paired t-test (SPSS version 6.0). There was a significant reduction of adhesion with platinum in the Staph Aureus and titanium group while the reduction in the Staph Epidermidis and titanium group did not reach statistical significance.
Conclusion: The use of platinum to manipulate the microcurrent around metallic implants reduces bacterial biofilm formation in vitro. This has obvious clinical implications in prevention of implant infections.
The abstracts were prepared by Mr Ray Moran. Correspondence should be addressed to him at Irish Orthopaedic Associaton, Secretariat, c/o Cappagh National Orthopaedic Hospital, Finglas, Dublin 11.
