Hydroquinone-quinone oxidation by molecular oxygen: a simple tool for signal amplification through auto-generation of hydrogen peroxide.

Signal amplification methods are of obvious importance for various diagnostic assays. We have developed a new small-molecule-based probe that, upon activation with sub-stoichiometric amounts of hydrogen peroxide, produces an auto-inductive amplification reaction. The signal is produced through the oxidation reaction of hydroquinone to the corresponding quinone derivative by molecular oxygen. This oxidation is accompanied by the formation of hydrogen peroxide, which can enter the amplification sequence and initiate a new diagnostic cycle. The generated quinone is composed of a donor-acceptor conjugated pair and fluoresces at a distinct wavelength, allowing the formation to be monitored by a convenient fluorescence assay.