RESUMO
AIM: Antibiotic resistance is an increasingly serious worldwide problem that needs to be addressed with alternative tools. Antimicrobial photodynamic therapy seems a promising approach but in some cases the synthesis of highly efficient photosensitizers requires laborious processes burdened by extensive chromatographic purifications. In this study, we evaluate the suitability of a formulation (Form-1) containing porphyrins bearing different charges, obtained during the synthesis of the highly efficient photosensitizer 5,10,15-tris(1-methylpyridinium-4-yl)-20-(pentafluorophenyl)porphyrin tri-iodide. RESULTS: Form-1 was equally effective in the photoinactivation of Escherichia coli and Staphylococcus aureus (reductions >5 log) as the best stand-alone photosensitizer. CONCLUSION: The effective reduction of bacteria with Form-1 provided promising indications supporting its use, leading to a substantial decrease in costs and production time.
Assuntos
Antibacterianos/farmacologia , Composição de Medicamentos , Escherichia coli/efeitos dos fármacos , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/química , Cátions/química , Relação Dose-Resposta a Droga , Farmacorresistência Bacteriana/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Humanos , Testes de Sensibilidade Microbiana , Modelos Moleculares , Estrutura Molecular , Processos Fotoquímicos , Fotoquimioterapia , Fármacos Fotossensibilizantes/química , Porfirinas/química , Staphylococcus aureus/crescimento & desenvolvimento , Relação Estrutura-AtividadeRESUMO
AIM: Conventional disinfection techniques, considered safe for plasma, are usually associated with collateral damages on concentrated platelets and erythrocytes. Alternative methods are required and antimicrobial photodynamic therapy (aPDT) seems promising. In this study the effectiveness of two photosensitizers (PS), a porphyrin and a phthalocyanine, to disinfect blood products was evaluated. RESULTS: The cationic porphyrin was more effective in the photoinactivation of bacteria. Also, no significant osmotic stress was found for samples treated with PS at 5.0 µM in isotonic conditions after antimicrobial photodynamic therapy. CONCLUSION: Effective reduction of Gram-positive bacteria at 5.0 µM of PS provided promising indications toward its safe use to disinfect blood samples. For Gram-negative bacteria, lower PS concentrations, between 5.0 and 10 µM, must be tested.
