Does Singlet Oxygen Contribute to the Oxygen Effect?

Singlet Oxygen

Singlet oxygen (O2) is a higher energy state molecular oxygen species. It is one of the most active intermediates involved in chemical and biochemical reactions. To fully appreciate the reactivity of O2, it is necessary to understand its physical and chemical nature. This paper reviews the generation, quenching and detection of O2. Its properties, possible chemical reactions are presented as we...

Singlet Oxygen Trapping Porphyrins

Fiber-optic Singlet Oxygen

Traditionally, Type II heterogeneous photo-oxidations produce singlet oxygen via external irradiation of a sensitizer and external supply of ground-state oxygen. A potential improvement is reported here. A hollow-core fiber-optic device was developed with an ‘‘internal’’ supply of light and flowing oxygen, and a porous photosensitizer-end capped configuration. Singlet oxygen was delivered throu...

Singlet Oxygen-Induced Arrhythmias

In a study of aerobically perfused rat hearts, the in situ photoactivation (530-590 nm) of rose bengal (a process that leads to the production of singlet oxygen and superoxide) has been shown to lead to the rapid development of electrocardiographic abnormalities and arrhythmias. With rose bengal concentrations of 1,000, 500, 250, 100, and 50 nmol/l (n =6/group), photoactivation (3,600 lx) led t...

SINGLET OXYGEN RESISTANT 1 links reactive electrophile signaling to singlet oxygen acclimation in Chlamydomonas reinhardtii.

Acclimation of Chlamydomonas reinhardtii cells to low levels of singlet oxygen, produced either by photoreactive chemicals or high light treatment, induces a specific genetic response that strongly increases the tolerance of the algae to subsequent exposure to normally lethal singlet oxygen-producing conditions. The genetic response includes the increased expression of various oxidative stress ...