Unraveling the Photodynamic Activity of Cationic Benzoporphyrin-Based Photosensitizers against Bladder Cancer Cells

Abstract

In this study, we report the preparation of new mono-charged benzoporphyrin complexes by reaction of the appropriate neutral benzoporphyrin with (2,2′-bipyridine)dichloroplatinum(II) and of the analogs’ derivatives synthesized through alkylation of the neutral scaffold with iodomethane. All derivatives were incorporated into polyvinylpyrrolidone (PVP) micelles. The ability of the resultant formulations to generate reactive oxygen species was evaluated, mainly the singlet oxygen formation. Then, the capability of the PVP formulations to act as photosensitizers against bladder cancer cells was assessed. Some of the studied formulations were the most active photosensitizers causing a decrease in HT-1376 cells’ viability. This creates an avenue to further studies related to bladder cancer cells.

New Bis-Cyclometalated Iridium(III) Complexes with β-Substituted Porphyrin-Arylbipyridine as the Ancillary Ligand: Electrochemical and Photophysical Insights

“…The structures of derivatives 2 were unambiguously established by spectroscopic data, namely NMR spectroscopy ( 1 H, 13 C, and COSY) and mass spectrometry techniques (Figures S1-S14 in Supplementary Information). The asymmetry of the bipyridine moiety was confirmed by the 1 H NMR spectra with two distinguishing duplets at ca.…”

“…The monitorization of the reaction progress by TLC showed, after 2 h, the total consumption of the starting porphyrin-bipyridine derivatives 2, with the formation of a more polar product. After the work-up, chromatographic purification, and crystallization (see details in Materials and Methods), compounds 4a-c were isolated in excellent yields (93-96%) and their structures were confirmed by NMR spectroscopy ( 1 H, 13 C, and COSY) and mass spectrometry techniques (Figures S16-S39 in Supplementary Information).…”

“…1 H and 13 C solution NMR spectra were recorded on Bruker Avance 300 (300.13 and 75.47 MHz, respectively), 500 (500.13 and 125.76 MHz, respectively), and 700 (700.13 MHz) spectrometers. CDCl 3 was used as solvent and tetramethylsilane (TMS) as internal reference; the chemical shifts are expressed in δ (ppm) and the coupling constants (J) in Hertz (Hz).…”

“…More recently, this type of compounds shows promising features to be used as alternatives to the platinum-based anti-tumor drugs, like cisplatin, which have demonstrated several disadvantages such as neurotoxicity, elevated blood pressure, induce hearing, kidney damage, nauseas, among others. However, development of cancer cell resistance is the major drawback related to the used of platinum-based drugs [ 13 , 14 , 15 , 16 , 17 , 18 ].…”

“…Our interest is centered on the functionalization of β-pyrrolic positions of meso -tetraarylporphyrins aiming to prepare new porphyrinic derivatives with adequate properties to be used in different fields [ 57 ], namely as photosensitizers in Photodynamic Therapy (PDT) or antimicrobial PDT [ 13 , 58 , 59 , 60 , 61 , 62 , 63 , 64 ]. We then report here an efficient synthetic approach to obtain a novel series of mononuclear heteroleptic porphyrin-iridium(III) complexes 4 and 5 via porphyrin derivatives 2 bearing a bipyridine unit (see Scheme 1 and Scheme 2 ).…”