Microemulsions are highly effective anti-biofilm agents

Aims: The demonstration of the antibiofilm effects of pharmaceutical microemulsions. Methods and Results: Microemulsions were prepared as physically stable oil/water systems. Previous work by this group has shown that microemulsions are highly effective antimembrane agents that result in rapid losses of viability in planktonic populations of Pseudomonas aeruginosa and Staphylococcus aureus . In this experiment a microemulsion preparation was used upon established biofilm cultures of Ps. aeruginosa PA01 for a period of 4 h. The planktonic MIC of sodium pyrithione and the planktonic and biofilm MICs of cetrimide were used as positive controls and a biofilm was exposed to a volume of normal sterile saline as a treatment (negative) control. Results indicate three log-cycle reductions in viability within the microemulsion treated biofilm, as compared to those observed in control treatments of similar biofilms (one log-cycle reduction in viabilities). Conclusions: The results indicate that the microemulsions are highly effective antibiofilm agents. Significance and Impact of the Study: This study suggests that microemulsions may have a role in the treatment of industrial and environmental biofilms.