Control of bacterial biofilms formed on pacifiers by antimicrobial solutions in spray

The aim was to evaluate the use of vinegar, hydrogen peroxide and sodium bicarbonate solutions for the disinfection of pacifiers.

Different types and concentrations of the substances were screened in planktonic and biofilm for antimicrobial activity on Streptococcus mutans, Staphylococcus pyogenes, Staphylococcus aureus and Escherichia coli. Also, the effect of the most effective substance was tested against polymicrobial biofilms aiming to mimic the multispecies colonization found in a pacifier.

Based on the agar diffusion test, minimal inhibitory concentration (MIC) and minimal microbicide concentration assays, 70% apple vinegar (70%AV) and 70% hydrogen peroxide (70%HP) were selected (P < 0.05). All tested solutions were able to significantly reduce viable cells of S. pyogenes, S. mutans and E. coli from the biofilms A statistically significant reduction of viable cells in S. aureus biofilms were observed after treatment with 70%AV in comparison to the other treatments. When compared to other microbial species, it was found that 70%HP was particularly effective against E. coli. The solution of 70%HP was able to reduce the viable cells of Enterobacteriaceae/pseudomonas of a polymicrobial biofilm formed from a pacifier. The other solutions were not effective in relation to control group.

Solutions of 70% HP showed to be a good alternative for chlorhexidine digluconate for the disinfection of pacifiers.