Synthesis and photodynamic effects of new porphyrin/4-oxoquinoline derivatives in the inactivation of S. aureus

New porphyrin/4-oxoquinoline conjugates were synthesized and shown to be excellent photosensitizing agents in the inactivation of S. aureus by the antimicrobial photodynamic therapy protocol.

Photodynamic effect of glycochlorin conjugates in human cancer epithelial cells

The effect of glycochlorins in HeLa cells shows that the galactose conjugate is the most efficient photosensitizer.

Selective photodynamic therapy induced by preirradiation of galactopyranosyl Zn(II) phthalocyanines with UV and red lights

The challenging task in the photodynamic therapy is the optimization of the procedure in a way to reach maximal selectivity of the phototoxic effect to tumor vs. non-neoplastic cells. The present study explores the impact of the light exposure with harmless UV 365 nm and low intensity visible red 637 nm light during incubation period on the uptake, primary localization, re-localization and photocytotoxic effect of tetra-galactopyranosyl substituted Zn ( II ) phthalocyanines. The studies were carried out on cancer cells (MDA-MB-231) and on non-tumorigenic cells (Balb/c 3T3, clone 31). The experimentals suggested that in addition to the favorable chemical structure of the applied amphiphilic protected galactose Zn ( II ) phthalocyanines, the pretreatment with UV 365 nm and visible red 637 nm light applied prior therapeutic light, lead to selective phototoxic effects on tumor cells.

Tumor targeting in photodynamic therapy. From glycoconjugated photosensitizers to glycodendrimeric one. Concept, design and properties

In this paper, we discuss the evolution over the last 15 years in the Curie Institute of the concept, the development of the design and some properties of glycoconjugated photosensitizers with the aim to optimize the tumor targeting in photodynamic therapy. By this research, we have shown that specific interactions between a mannose-lectin and trimannosylglycodendrimeric porphyrins contributed to a larger extent than non-specific ones to the overall interaction of a glycosylated tetraarylporphyrin with a membrane. The studies of in vitro photocytotoxicity showed the relevance of the global geometry of the photosensitizer, the number and position of the linked glycopyranosyl groups on the chromophore and their lipophilicity. The two best compounds appeared to be porphyrins bearing three α-glycosyl groups on para-position of meso-phenyl via a flexible linker. Compound bearing α-manosyl moieties was evaluated successfully in two in vivo xenografted animal models of human retinoblastoma and colorectal cancers. Conversely, the presence on the chromophore of three sugars via a glycodendrimeric moiety induced a potential cluster effect, but decreased the in vitro photoefficiency despite a good affinity for a mannose-lectin.

Synthesis and photophysical properties of thioglycosylated chlorins, isobacteriochlorins, and bacteriochlorins for bioimaging and diagnostics

The facile synthesis and photophysical properties of three nonhydrolyzable thioglycosylated porphyrinoids are reported. Starting from meso-perfluorophenylporphyrin, the nonhydrolyzable thioglycosylated porphyrin (PGlc₄), chlorin (CGlc₄), isobacteriochlorin (IGlc₄), and bacteriochlorin (BGlc₄) can be made in 2-3 steps. The ability to append a wide range of targeting agents onto the perfluorophenyl moieties, the chemical stability, and the ability to fine-tune the photophysical properties of the chromophores make this a suitable platform for development of biochemical tags, diagnostics, or as photodynamic therapeutic agents. Compared to the porphyrin in phosphate buffered saline, CGlc₄ has a markedly greater absorbance of red light near 650 nm and a 6-fold increase in fluorescence quantum yield, whereas IGlc₄ has broad Q-bands and a 12-fold increase in fluorescence quantum yield. BGlc₄ has a similar fluorescence quantum yield to PGlc₄ (<10%), but the lowest-energy absorption/emission peaks of BGlc₄ are considerably red-shifted to near 730 nm with a nearly 50-fold greater absorbance, which may allow this conjugate to be an effective PDT agent. The uptake of CGlc₄, IGlc₄, and BGlc₄ derivatives into cells such as human breast cancer cells MDA-MB-231 and K:Molv NIH 3T3 mouse fibroblast cells can be observed at nanomolar concentrations. Photobleaching under these conditions is minimal.