XANTHENE DYES-MEDIATED IN VITRO PHOTODYNAMIC TREATMENT OF CANCER AND NON-CANCER CELL LINES

Rose bengal and erythrosin B are xanthene dyes mainly known and used as antimicrobial agents, but due to their photodynamic activity they are also potential photosensitizers for cancer photodynamic therapy. The aim of this work is to study a photodynamic efficacy of rose bengal and erythrosin B against human skin melanoma and mouse fibroblast cell lines, compare them with each other and find out their photodynamic properties induced by light emitting diodes with total light dose of 5 J/cm2. To fully identify and understand photodynamic properties of both potentially effective photosensitizers, a set of complex in vitro tests such as cell cytotoxic assay, measurement of reactive oxygen species production, mitochondrial membrane potential change assay, mode of cell death determination or comet assay were made. Although both photosensitizers proved to have similar properties such as increasing production of reactive oxygen species with the higher concentration, predominance of necrotic mode of death or genotoxicity, the more effective photosensitizer was rose bengal because its EC50 was over 20 times lower for both cell lines than in case of erythrosin B.

Facile One-Step Preparation and Efficient Photocatalytic Hydrogen Production of Composite MoS2/g-C3N4 Sensitized by Erythrosin B

MoS2/g-C3N4 (g-C3N4 [Formula: see text] graphitic carbon nitride) composite is considered as a promising photocatalyst for hydrogen production, while the preparation method still needs to be improved. Herein for the first time, nanosized MoS3 and melamine were used as starting materials and a facile one-pot calcination method was successfully applied for the synthesis of MoS2/g-C3N4. The physical and photophysical properties of the as-prepared MoS2/g-C3N4 were characterized by XRD, IR, SEM, TEM and XPS techniques. Sensitized by Erythrosin B (EB), the photocatalytic hydrogen production performance of MoS2/g-C3N4 was investigated and the amount of MoS2 was optimized. An excellent H2 production activity of 1091.2[Formula: see text][Formula: see text] was achieved for 43% MoS2/g-C3N4, which is about 330 times that of pure g-C3N4 (3.3[Formula: see text][Formula: see text]. In addition, its performance was compared with those of three other MoS2/g-C3N4 samples prepared by conventional methods and a possible mechanism of H2 production was proposed based on the photoluminescence and photoelectrochemical results.

Anionic Surfactant Sensing by Optical Properties of Erythrosin B

The nonlinear optical properties, absorbance and fluorescence spectra of Erythrosin B (ErB) aqueous solution in different CTAB concentration was studied. Z-scan technique under laser light excitation at 532 nm, was used for study reverse saturable absorption (RSA) of ErB. it was observed that the RSA of solution depend on CTAB concentration. A enhancing of absorbance and quenching of fluorescence is observed with increase of CTAB concentration in solution and the RSA can reduce the fluorescence intensity. It was proposed that the micelle can reduce the dye aggregation is solutions and it can affect on linear and nonlinear optical properties of ErB.

Titanate nanotube confined merger of organic photocatalysis and TEMPO catalysis for highly selective aerobic oxidation of sulfides

Here, it is discovered that titanate (H2Ti3O7) nanotubes can confine the merger of erythrosin B (ErB) photocatalysis and TEMPO catalysis for highly selective aerobic oxidation of sulfides under irradiation of green light-emitting diodes (LEDs).