Efeito antimicrobiano de formulações de azul de metileno com carreador de oxigênio em diferentes pHs

Abstract

The aim of this study was to evaluate the antimicrobial photodynamic effect of methylene blue (MB) formulations containing oxygen carrier at different pHs in antimicrobial photodynamic therapy (PDT). Biofilms of Pseudomonas aeruginosa PA01 formed about acrylics specimens during five days were treated PDT with the different formulations: AM 7.4; AM 5.6; AM/carrier 7.4; AM/carrier 5.6. Biofilms not exposed to treatment was used as control. A blind examiner for the experimental groups performed the counting of colonies formed on the plates and calculating of colony forming unit (CFU) per ml suspension (CFU/mL). Two-factor ANOVA was used to determine the effect of factors solvent (carrier versus water) and pH (7.4 versus 5.6). One factor ANOVA and post hoc Tukey test was used to evaluate differences among the five comparator groups (control, AM/carrier 7.4, AM 7.4; AM/carrier 5.6, AM 5.6). The Statistica 8.0 software was used for all analyzes. Significace level of 5 % was used to all such assessments. All of photodynamic therapy groups showed a statistically significant reduction in P. aeruginosa compared to the control group. When the carrier has been used, AM formulation at pH 7.4 presented a statistically greater reduction of P. aeruginosa than the formulation with pH 5.6.