Water-Soluble Dicationic Deuteroporphyrin Derivative for Antimicrobial PDT: Singlet Oxygen Generation, Passive Carrier Interaction and Nosocomial Bacterial Strains Photoinactivation

Multidrug resistance of pathogenic microflora is a serious threat to the modern community looking for new approaches treating superinfections. In this sense, antimicrobial photodynamic therapy (aPDT) an effective and safe technique considered be promising alternative or important supplement traditional clinically applied methods inactivating antibiotic resistant pathogens. Macroheterocyclic photosensitizers (PS) three generations are proposed clinical practice. They known as key compounds PDT able localized selectively in microbial cells activated with red light producing toxic reactive oxygen species (ROS). However, these neutral anionic PSs possess low affinity towards outer lipopolysaccharide membrane Gram-negative bacteria and, consequently, poor ability kill pathogens under irradiation. contrast, cationic containing one more charged groups, especially those bound appropriate carrier, provide efficient inactivation microorganisms. paper, we focus on study photophysics, aggregation photoinduced activity water-soluble derivative deuteroporphyrin-IX, blood group porphyrin, bearing two trialkylammonium fragments. This potential photosensitizing agent found generate singlet non-polar environment forms stable nano-sized molecular complexes passive non-ionic carrier Tween 80, localizing aqueous surfactant solution non-aggregated form surface micellar layer. Two different modes PS/Tween 80 binding characterized by their own stability constants interaction stoichiometry observed. Microbiological experiments clearly demonstrate that increased permeability bacterial caused application intramicellar photosensitizer addition some potentiation agents leads pronounced phototoxicity pigment against antibiotic-resistant nosocomial strains