TMPyP‐mediated photoinactivation of Pseudomonas aeruginosa improved in the presence of a cationic polymer

CAMPAGNO, LUCIANA PAULA; QUIROGA; EZEQUIEL D.; DURANTINI, EDGARDO; ALOVERO, FABIANA L.

PHOTOCHEMISTRY AND PHOTOBIOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2023

0031-8655

seudomonas aeruginosa is one of the most refractory organisms to antibiotic treatment and appears to be one of the least susceptible to photodynamic treatment. TMPyP is effective in the photoinactivation of P.aeruginosa, and the coadministration with the cationic polymer EudragitE100 (Eu) potentiates this effect against isolates both sensitive and resistant to antibiotics. The fluorescentpopulation (>98%) observed by flow cytometry after exposure to Eu+TMPyP remained unchanged after successive washings, indicating a stronger interaction/internalization of TMPyP in the bacteria, which could be attributed to the rapid neutralization of surface charges. TMPyP and Eu produced depolarization of the cytoplasmic membrane, which increased when both cationic compounds were combined. Using confocal laser scanning microscopy, heterogeneously distributed fluorescent areas were observed after TMPyP exposure, while homogeneous fluorescence and enhanced intensity were observed with Eu+TMPyP. The pol