Singlet oxygen production by a polypyridine ruthenium (II) complex with a perylene monoimide derivative: A strategy for photodynamic inactivation of Candida albicans

Author(s)

Sousa Maia, Paulo Jose ^{[1, 2, 3]} ; de Aguiar, Inara ^[2] ; Velloso, Marisol dos Santos ^[4] ; Zhang, Dong ^[3] ; dos Santos, Edjane Rocha ^[2] ; de Oliveira, Jonatas Rafael ^[4] ; Junqueira, Juliana Campos ^[4] ; Selke, Matthias ^[3] ; Carlos, Rose Maria ^[2]

Affiliation

^[1] Univ Fed Amazonas, Inst Exact Sci & Technol, BR-69103128 Itacoatiara, AM - Brazil

^[2] Univ Fed Sao Carlos, Dept Chem, CP 676, BR-13565905 Sao Carlos, SP - Brazil

^[3] Calif State Univ Los Angeles, Dept Chem & Biochem, Los Angeles, CA 90032 - USA

^[4] Univ Estadual Paulista, UNESP, Dept Biosci & Oral Diag, Av Engenheiro Francisco Jose Longo 777, BR-12245000 Sao Jose Dos Campos, SP - Brazil

• Document type: Journal article
• Source: JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY; v. 353, p. 536-545, FEB 15 2018.
• Web of Science Citations: 4

Abstract

We report the synthesis, optical, electrochemical and electronic properties of a new perylene derivative and its Ru(II) complex, namely N,-(5-amino-1,10-phenantroline)perylene-3,4,9,10-tetracarboximonoimide (pPDI) and Bis(1,10-phenanthroline)(N-(5-amin-1,10-phenantroline)perylene-3,4,9,10- tetracarboxi monoimide)ruthenium(II) hexafluorophosphate, {[}Ru(phen)(2)(pPDI](2+) ({[}PF6](-))(2). The molecular structures of the compounds were elucidated by FTIR, mass spectrometry, elemental analysis (CHN) and DFT calculations. Their optical and electrochemical properties were investigated by absorption and fluorescence spectroscopy and cyclic voltammetry. The spectroscopic and electrochemical studies for both the pPDI and the perylene monoimide metal complex show that Ru2+ coordination does not affect the optical and electrochemical properties of the free perylene bisimide ligand. The Ru complex exhibits emission lifetimes of 5.06 ns (48.1%) and 156 ns (51.9%), resulting from emission of the pPDI ligand and (MLCT)-M-3, respectively. The pPDI triplet excited state in the title chromophore is able to sensitize the production of singlet oxygen (O-1(2)). Using a time-resolved laser system, we measured the quantum yield for the production of singlet oxygen (Phi Delta) to be 0.26 for cis-{[}Ru(phen)(2)(pPDI)](2+). Carzdida albicans is recognized as the most common fungal pathogens, causing superficial infections of the skin and mucous membranes. Resistance of C. albicans strains against classical antifungal agents such as fluconazole has increased considerably, which drives the search for new therapeutic alternatives. In the present study, we report that our new Ru-perylene complex can indeed be used to kill the bacterium C. albicans. The fungicidal activity of cis-{[}Ru(phen)(2)(pPDI)](2+) against C. albicans was evaluated in the presence of C. albicans cultures in the dark and in the presence of light. After exposure to 12.5 mu M of cis-{[}Ru (phen)(2)(pPDI)](2) in the presence of light for 180 s, C. albicans showed a decrease of 50% in its concentration compared to the same experimental conditions in the dark. (C) 2017 Elsevier B.V. All rights reserved. (AU)

• FAPESP's process: 14/17476-0 - Green photochemistry: development of transition metal complexes for activation of luminescent singlet oxygen and its application in the disinfection of wastewaters contaminated with pathogenic microorganisms (Escherichia coli and Enterococcus faecalis)
• Grantee: Paulo José de Sousa Maia
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• FAPESP's process: 12/09449-8 - Photochemistry "green": Development of transition metal complexes for activation of luminescent singlet oxygen and its application in the disinfection of water contaminated with pathogenic microorganisms (Escherichia coli and Enterococcus faecalis)
• Grantee: Paulo José de Sousa Maia
• Support Opportunities: Scholarships in Brazil - Doctorate