chlorin-p6 and phytochlorin

The effect of photodynamic therapy (PDT) is dependent on the localization of photosensitizer in the treatment volume at the time of illumination. Investigation of photosensitizer pharmacokinetics in and around the treatment volume aids in determining the optimal drug light interval for PDT.. In this paper we have investigated the distribution of the photosensitizers chlorin e6 and Bremachlorin in the oral squamous cell carcinoma cell-line OSC19-Luc-Gfp in a tongue tumor, tumor boundary, invasive tumor boundary, and normal tongue tissue by the use of confocal microscopy of frozen sections. Tongues were harvested at t = [3, 4.5, 6, 24, 48] hours after injection.. Both photosensitizers showed a decreasing fluorescence with increasing incubation time, and at all time points higher fluorescence was measured in tumor boundary than in tumor itself. For short incubation times, a higher fluorescence intensity was observed in the invasive tumor border and normal tissue compared to tumor tissue. Bremachlorin showed a small increase in tumor to normal ratio at 24 and 48 hours incubation time. Ce6 was undetectable at 48 hours. We did not find a correlation between photosensitizer localization and the presence of vasculature.. The modest tumor/tumor boundary to normal selectivity of between 1.2 and 2.5 exhibited by Bremachlorin 24 and 48 hours after administration may allow selective targeting of tongue tumors. Further studies investigating the relationship between Bremachlorin concentration and therapeutic efficacy PDT with long incubation times are warranted.

Topics: Animals; Carcinoma, Squamous Cell; Chlorophyllides; Drug Combinations; Mice; Mice, Inbred BALB C; Microscopy, Confocal; Photochemotherapy; Photosensitizing Agents; Porphyrins; Random Allocation; Tongue Neoplasms

The use of photoactivated disinfection has had a significant medical and technological effect in bacterial inactivation, as an alternative to conventional antimicrobial methods. The main goal of this study was to investigate the effect of photoactivated disinfection on Streptococcus mutans, when Radachlorin(®) was used as a photosensitizer.. Streptococcus mutans samples of two different initial concentrations were treated with Radachlorin(®) gel (0.1%), irradiated by the light of a He-Ne laser (633nm), with energy density of 6J/cm(2), and cell viability was evaluated after culturing.. It was observed that the combination of Radachlorin(®) and laser was more effective than Radachlorin(®) or laser alone (p<0.05), in reduction of S. mutans and Radachlorin(®) was cytotoxic, in the dark, only for the lower concentration of bacteria. Lower concentration of S. mutans resulted in higher amount of killing, in the case of using Radachlorin(®) with or without laser.. The photoactivation of Radachlorin(®) using a He-Ne laser could inactivate S. mutans to a significant level. In addition Radachlorin(®) might be cytotoxic in the dark, for the lower concentration of bacteria.

Topics: Anti-Bacterial Agents; Bacterial Load; Chlorophyllides; Darkness; Disinfection; Drug Combinations; Humans; Lasers, Gas; Materials Testing; Microbial Viability; Photosensitizing Agents; Porphyrins; Radiation Dosage; Streptococcus mutans

Novel benzochloroporphyrin derivatives (BCPDs) were designed, synthesized, and characterized. In vitro dark cytotoxicity and photodynamic efficacy of BCPDs were evaluated by MTT assay on human hepatoma BEL-7402 cells. The experimental results showed that BCPDs 15, 16, 17, and 18 have strong long wavelength absorptions around 670 nm and exhibit significantly lower dark cytotoxicity than BPDMA and possess potent photocytotoxicity, IC50 values 1.32 microg/mL for 15, 0.26 microg/mL for 16, 0.47 microg/mL for 17 of 0.27 microg/mL for 18, and 0.23 microg/mL for BPDMA. Among them, BCPDs 16 and 18 are more effective and promising PDT photosensitizers based on the studies with BEL-7402 cells and show nearly the same photodynamic efficacy as BPDMA. MG-P staining qualitative analysis also indicated that PDT with BCPDs 16 can induce apoptosis in BEL7402 cells.

Topics: Carcinoma, Hepatocellular; Cell Line, Tumor; Chlorophyllides; Drug Design; Humans; Liver Neoplasms; Photochemotherapy; Photosensitizing Agents; Porphyrins; Protoporphyrins; Spectrophotometry, Ultraviolet