Decomposition of methyl orange using C-60 fullerene adsorbed on silica gel as a photocatalyst via visible-light induced electron transfer

Visible-light induced electron transfer reactions of C60 fullerene adsorbed on silica gel (C60/SiO2 powder) to methyl orange in water have been studied. The C60/SiO2 powder was simply prepared by mixing a toluene solution of the C60 fullerene with silica gel followed by evaporating the toluene. Irradiation by visible light (>420 nm) of the methyl orange aqueous solution (25 μM) in the presence of the C60/SiO2 powder and ascorbic acid resulted in the decomposition of the methyl orange. These results showed that the degradation conversion reached 96% after a 25-min visible light irradiation. The reaction also occurred by the irradiation of sunlight. The reductive products of methyl orange, N,N-dimethyl-p-phenylenediamine and sulfanilic acid, were ascertained and monitored by liquid chromatography/mass spectrometry (LC/MS). The reaction did not occur in the dark and in the absence of C60/SiO2 or ascorbic acid. The possible mechanism of the reaction is discussed. Furthermore, the C60/SiO2 powder was applied to a continuous flow system for the photodecomposition of methyl orange. C60/SiO2 powder was packed in a glass tube. The methyl orange solution was pumped into the glass tube, and the tube was irradiated by visible light or sunlight. The continuous decomposition of methyl orange was achieved by this method.ArticleAPPLIED CATALYSIS B-ENVIRONMENTAL. 166:544-550 (2015)journal articl

Decomposition of methyl orange using C60 fullerene adsorbed on silica gel as a photocatalyst via visible-light induced electron transfer

Visible-light induced electron transfer reactions of C60 fullerene adsorbed on silica gel (C60/SiO2 powder) to methyl orange in water have been studied. The C60/SiO2 powder was simply prepared by mixing a toluene solution of the C60 fullerene with silica gel followed by evaporating the toluene. Irradiation by visible light (>420 nm) of the methyl orange aqueous solution (25 μM) in the presence of the C60/SiO2 powder and ascorbic acid resulted in the decomposition of the methyl orange. These results showed that the degradation conversion reached 96% after a 25-min visible light irradiation. The reaction also occurred by the irradiation of sunlight. The reductive products of methyl orange, N,N-dimethyl-p-phenylenediamine and sulfanilic acid, were ascertained and monitored by liquid chromatography/mass spectrometry (LC/MS). The reaction did not occur in the dark and in the absence of C60/SiO2 or ascorbic acid. The possible mechanism of the reaction is discussed. Furthermore, the C60/SiO2 powder was applied to a continuous flow system for the photodecomposition of methyl orange. C60/SiO2 powder was packed in a glass tube. The methyl orange solution was pumped into the glass tube, and the tube was irradiated by visible light or sunlight. The continuous decomposition of methyl orange was achieved by this method.ArticleAPPLIED CATALYSIS B-ENVIRONMENTAL. 166:544-550 (2015)journal articl

Involvement of I-BAR protein IRSp53 in tumor cell growth via extracellular microvesicle secretion

Cellular protrusions mediated by the membrane-deforming I-BAR domain protein IRSp53 are involved in cell migration, including metastasis. However, the role of IRSp53 in cell proliferation remains unclear. Here, we examined the role of IRSp53 in cell proliferation and found that it acts through secretion. Coculture of gingiva squamous carcinoma Ca9-22 cells and their IRSp53-knockout cells restored proliferation to parental Ca9-22 cell levels, suggesting possible secretion dependent on IRSp53. Notably, the amounts of microvesicle fraction proteins that were secreted into the culture medium were reduced in the IRSp53-knockout cells. The IRSp53-knockout cells exhibited decreased phosphorylation of mitogen-activated protein kinase, suggesting the decrease in the proliferation signals. The phosphorylation was restored by the addition of the microvesicles. In mice xenograft Ca9-22 cells, IRSp53-containing particles were secreted around the xenograft, indicating that IRSp53-dependent secretion occurs in vivo. In a tumor mice model, IRSp53 deficiency elongated lifespan. In some human cancers, the higher levels of IRSp53 mRNA expression was found to be correlated with shorter survival years. Therefore, IRSp53 is involved in tumor progression and secretion for cellular proliferation