Dissolved organic matter (DOM) is both a promoter and an inhibitor of triplet-induced organic contaminant oxidation. This dual role was systematically investigated through photochemical experiments with three types of DOM of terrestrial and aquatic origins that were preoxidized to varying extents by ozonation. The inhibitory effect of DOM was assessed by determining the 4-carboxybenzophenone ph...

The association of PhotoSensitizer (PS) molecules with nanoparticles (NPs) forming photosensitizing NPs, has emerged as a therapeutic strategy to improve PS tumor targeting, to protect PS from deactivation reactions and to enhance both PS solubility and circulation time. Since association with NPs usually alters PS photophysical and photochemical properties, photosensitizing NPs are an importan...

BACKGROUND Many commonly used medications, including both medications for long-term (daily) use and short-term use (treatment courses of finite duration), have photosensitizing properties. Whether use of these medications affects skin cancer risk, however, is unclear. METHODS Using a cohort of all Danish residents ≥15 years old in 1995 to 2006 (n = 4,761,749) and information from Danish natio...

ownload kground: Many commonly used medications, including both medications for long-term (daily) use and term use (treatment courses of finite duration), have photosensitizing properties. Whether use of these ations affects skin cancer risk, however, is unclear. thods: Using a cohort of all Danish residents ≥15 years old in 1995 to 2006 (n = 4,761,749) and inforfrom Danish national registers, ...

The Authors have studied the capacity to photoreact with native DNA and r-RNA using six coumarins and four 4',5'-dihydro-furo-coumarins. Six of these substances have shown a definite photoreactivity both with DNA and r-RNA, even if in a very much lower extent in respect to that of skin-photosensitizing furocoumarins. The low capacity to photoreact with nucleic acids of these substances is discu...

Photodynamic therapy (PDT) is a treatment that uses light-sensitive drugs and light source to destroy cancer cells. Methylene blue (MB) an efficient photosensitizing agent has been widely used in PDT. However, MB suffers from the hypochromic effect caused by self-aggregation DNA binding vivo. It also easily reduced ineffective leucomethylene hypoxic environments surrounding solid tumors. In thi...

The cell-permeable anthracene analog diethyl-3-3'-(9,10-anthracenediyl)bis acrylate (DADB) was recently identified as a highly selective probe for singlet oxygen ((1)O(2)). Now, we show that DADB can be used to monitor (1)O(2) formation in cell culture during photodynamic therapy. An atypical property of DADB is that fluorescence emission is decreased upon oxidation. Using photosensitizers that...