Souza, Beatriz Müller NunesPinto, Juliana GuerraPereira, André Henrique CorreiaMiñán, Alejandro GuillermoStrixino, Juliana Ferreira2025-06-092025-06-09https://repositorio.univap.br/handle/123456789/983Staphylococccus aureus is a ubiquitous and opportunistic bacteria associated with high mortality rates. Antimicrobial photodynamic therapy (aPDT) is based on the application of a light source and a photosensitizer that can interact with molecular oxygen, forming Reactive Oxygen Species (ROS) that result in bacterial inactivation. This study aimed to analyze, in vitro, the action of aPDT with Photodithazine® (PDZ) in methicillin-sensitive Staphylococcus aureus (MSSA) and methicillin-resistant Staphylococcus aureus (MRSA) strains. The strains were incubated with PDZ at 25, 50, 75, and 100 mg/L for 15 min and irradiated with fluences of 25, 50, and 100 J/cm2. The internalization of PDZ was evaluated by confocal microscopy, the bacterial growth by counting the number of colony-forming units, as well as the bacterial metabolic activity post-aPDT and the production of ROS. In both strains, the photosensitizer was internalized; the production of ROS increased when the aPDT was applied; there was a bacterial reduction compared to the control at all the evaluated fluences and concentrations; and, in most parameters, it was obtained complete inactivation with significant difference (p < 0.05). The implementation of aPDT with PDZ in clinical strains of S. aureus has resulted in its complete inactivation, including the MRSA strains.pdfenArtigos de PeriódicosBeatriz Müller Nunes SouzaJuliana Guerra PintoAndré Henrique Correia PereiraAlejandro Guillermo MiñánJuliana Ferreira-Strixino<http://doi.org/10.3390/antibiotics10070869>Antimicrobial photodynamic therapyMRSAMSSAPhotodithazine®Souza, B.M.N.; Pinto, J.G.; Pereira, A.H.C.; Miñán, A.G.; Ferreira-Strixino, J. Efficiency of Antimicrobial Photodynamic Therapy with Photodithazine® on MSSA and MRSA Strains. Antibiotics 2021, 10, 869. https://doi.org/10.3390/ antibiotics10070869University of Vale do ParaíbaUniversity of Vale do ParaíbaUniversity of Vale do ParaíbaUniversidad Nacional de La PlataUniversity of Vale do Paraíba