Direct Electrical Current Reduces Bacterial and Yeast Biofilm Formation

Abstract

New strategies are needed for prevention of biofilm formation. We have previously shown that 24 hr of 2,000 µ A of direct current (DC) reduces Staphylococcus epidermidis biofilm formation in vitro . Herein, we examined the effect of a lower amount of DC exposure on S. epidermidis , Staphylococcus aureus , Escherichia coli , Pseudomonas aeruginosa , Propionibacterium acnes , and Candida albicans biofilm formation. 12 hr of 500 µ A DC decreased S. epidermidis , S. aureus , E. coli , and P. aeruginosa biofilm formation on Teflon discs by 2, 1, 1, and 2 log 10 cfu/cm 2 , respectively ( p < 0.05 ). Reductions in S. epidermidis , S. aureus , and E. coli biofilm formation were observed with as few as 12 hr of 200 µ A DC (2, 2 and 0.4 log 10 cfu/cm 2 , resp.); a 1 log 10 cfu/cm 2 reduction in P. aeruginosa biofilm formation was observed at 36 hr. 24 hr of 500 µ A DC decreased C. albicans biofilm formation on Teflon discs by 2 log 10 cfu/cm 2 . No reduction in P. acnes biofilm formation was observed. 1 and 2 log 10 cfu/cm 2 reductions in E. coli and S. epidermidis biofilm formation on titanium discs, respectively, were observed with 12 hr of exposure to 500 µ A. Electrical current is a potential strategy to reduce biofilm formation on medical biomaterials.