Quenching effects of (-)-Epigallocatechin gallate for singlet oxygen production and its protection against oxidative damage induced by Ce6-mediated photodynamic therapy in vitro

BODIPY dyes have recently attracted attention as potential photosensitizers. In this work, commercial and novel photosensitizers (PSs) based on BODIPY chromophores (haloBODIPYs and orthogonal dimers strategically designed with intense bands in the blue, green or red region of the visible spectra and high singlet oxygen production) were covalently linked to mesoporous silica nanoparticles (MSNs) further functionalized with PEG and folic acid (FA). MSNs approximately 50 nm in size with different functional groups were synthesized to allow multiple alternatives of PS-PEG-FA decoration of their external surface. Different combinations varying the type of PS (commercial Rose Bengal, Thionine and Chlorine e6 or custom-made BODIPY-based), the linkage design, and the length of PEG are detailed. All the nanosystems were physicochemically characterized (morphology, diameter, size distribution and PS loaded amount) and photophysically studied (absorption capacity, fluorescence efficiency, and singlet oxygen production) in suspension. For the most promising PS-PEG-FA silica nanoplatforms, the biocompatibility in dark conditions and the phototoxicity under suitable irradiation wavelengths (blue, green, or red) at regulated light doses (10–15 J/cm2) were compared with PSs free in solution in HeLa cells in vitro.

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Combined effects of singlet oxygen and hydroxyl radical in photodynamic therapy with photostable bacteriochlorins: Evidence from intracellular fluorescence and increased photodynamic efficacy in vitro

Free Radical Biology and Medicine ◽

10.1016/j.freeradbiomed.2011.12.027 ◽

2012 ◽

Vol 52 (7) ◽

pp. 1188-1200 ◽

Cited By ~ 54

Author(s):

Janusz M. Dąbrowski ◽

Luis G. Arnaut ◽

Mariette M. Pereira ◽

Krystyna Urbańska ◽

Sérgio Simões ◽

...

Keyword(s):

Photodynamic Therapy ◽

Hydroxyl Radical ◽

Singlet Oxygen ◽

Combined Effects ◽

Intracellular Fluorescence

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The Photophysical Properties of Pyropheophorbide-a in Different Laser Light and PDT Efficiency for Eca-109 Cell In Vitro

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.393-395.1029 ◽

2011 ◽

Vol 393-395 ◽

pp. 1029-1032

Author(s):

Hui Jing Mao ◽

Zhi Long Chen ◽

Ying Ye

Keyword(s):

Singlet Oxygen ◽

Laser Light ◽

Photophysical Properties ◽

Oxygen Probe ◽

Oxygen Production ◽

Light Power ◽

Oxygen Generation ◽

Pyropheophorbide A ◽

Single Oxygen

Pyropheophorbid-a (PyroPheo) is one of the well-known photosensitizers which can be useful for future clinical applications. This work is aimed to compare and measure generation rates of single oxygen through activation of pyropheophorbide-a by four different wavelength, and observe the sensitivity of pyropheophorbide-a mediated photodynamic therapy for eca-109 cell. Methods: UV-vis spectrophotometrics was used to measure decrease of singlet oxygen probe 9,10-dimethylanthracene(DPBF) so as to evaluate singlet oxygen production generation. The Eca-109 cells were were exposed to light (650nm) with a constant light power of 200mW/cm2, at a distance of 5cm, for 25 to 200 seconds. The results were measured by MTT assay. Results: pyropheophorbide-a in DMF solution irradiation by different light power can produce singlet oxygen quickly. Comparison of single oxygen generation rate has proved that photodynamic effect at 532nm is fastest, followed by 650nm, 635nm, 690nm which has correlation with absorbance of pyropheophorbide-a. The survival rate of cells dropped after irradiation by light what was significantly different from other groups. Conclusion: pyropheophorbide-a is an excellent photosensitizer and prooxidant. Through activated by different wavelength it could be apply to different disease

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