Structure-activity studies of di-cationic imidazolyl porphyrins for PDI of E. coli

• Published in: Photodiagnosis and photodynamic therapy 2024-04, Vol.46, p.104110, Article 104110
• Main Authors: Silva, Madalena F.C., Aroso, Rafael T., Arnaut, Zoe A., Dabrowski, Janusz M., Pucelik, Barbara, Barzowska, Agata, da Silva, Gabriela J., Arnaut, Luís G., Pereira, Mariette M.
• Format: Article
• Language: English
• Subjects: cationic imidazolyl porphyrins; E. coli; photodynamic inactivation; photosensitizers; structure/activity effects
• ISSN: 1572-1000; 1873-1597
• DOI: 10.1016/j.pdpdt.2024.104110

Several studies have underlined the potential use of cationic imidazolyl porphyrins as photosensitizers for PDI, specially for gram-negative bacteria, being the structure/activity effects one of the most important areas of study. This work incorporates the synthesis of di-cationic imidazolyl porphyrin-based photosensitizers, whose amphiphilicity was modulated in attempt to develop molecules with optimized structures and properties for the inactivation of E. coli. The developed family of cationic porphyrins was obtained with good yields and the photophysical and photochemical characterization of the synthesized compounds was performed, as well as biological studies in planktonic E. coli. The most promising results were observed for the photosensitizer bearing a bigger alkyl chain and OH groups at the end of the chain. These findings suggest that hydrophilic groups at the end of an alkyl chain promotes a higher inactivation of E. coli when compared to lipophilic groups and smaller alkyl chains.