Estudo da potencialidade da terapia fotodinâmica antimicrobiana (TFDA) na desinfecção de água

Abstract

Water is a fundamental element for the existence of all living beings. However, it's possible compromise it quality by anthropogenic influence, making the water carrier diseases due to the existence of microorganisms (many of these, pathogenic). To end these problems, the treatment of water has being done in various ways, such as using chemical or physical processes, for example. Antimicrobial Photodynamic Therapy (APDT) is based on the combination of these two procedures: a light source (physical) and a photo sensitizer (chemical). The FS added to the sample prepared in beakers was irradiated from LED bulbs, which excites and generates reactive oxygen species and these, in turn, generate an oxidative stress causing microbial death. Aiming to verify the potential of antimicrobial photodynamic therapy in the disinfection of water contaminated with Escherichia coli, using different photosensitizers, were performed tests to determine optimal concentrations for experimental use. From the radiation exposure times, compared to the concentrations used, the best results were obtained with concentrations of 1000μMol/L of methylene blue and 250μMol/L of malaquite green at the time of 15 minutes.