The detection sensitivity of commonly used singlet oxygen probes in aqueous environments.

The sensitivity for singlet oxygen (O) of two convenient O probes, 1,3-diphenylisobenzofuran (DPBF) and 9,10-Anthracenediyl-bis(methylene)dimalonic acid (ABDA), has been investigated in different aqueous environments. Both probes are commercially available at reasonable cost and can be used with standard UV-vis spectrometers. Although DPBF is not soluble in neat water and is not specific to the detection of O, it has very high, essentially diffusion-limited, reactivity towards O; it can trap up to 50% of all O created in alcohol/water or micellar solution, and even more when replacing HO by DO, which makes it highly useful when the process under investigation does not yield much O.