Singlet Oxygen Luminescence
Steady-state and time-resolved singlet oxygen luminescence
Singlet oxygen is a highly reactive species that can be generated by illuminating organic dyes (called photosensitizers) under aerobic conditions. This reactive species plays an important role in many photoinduced oxidative processes in both biology and chemistry, and is responsible, for example, for photochemical degradation of various materials or for destroying cancer cells during photodynamic therapy.
An excellent way to detect the presence of singlet oxygen are steady-state or time-resolved measurements of its characteristic phosphorescence at around 1270 nm. However, such measurements can be quite challenging due to the rather weak phosphorescence intensities (i.e. low emission quantum yield of singlet oxygen). The phosphorescence lifetime of singlet oxygen is solvent dependent and can therefore be used to gain information about the environment of the emitting oxygen molecules.