Chemiluminescence detection of hydroquinone with flow-injection analysis of luminol-hydrogen peroxide system catalyzed by Jacobsen's catalyst

In this research, an ultrasensitive, rapid and novel flow injection chemiluminescence (FI-CL) strategy has been validated for the determination of hydroquinone (HQ). It was found that the CL intensity of the luminol-hydrogen peroxide system could be enhanced sharply by Jacobsen's catalyst in alkaline solution and the joining of HQ was found to restrain the CL signal of the luminol-hydrogen peroxide reaction catalyzed by the Jacobsen's catalyst, which made it possible for the determination of HQ. Possible mechanism and series of instrumental and chemical arguments were discussed in detail. Under the selected experimental conditions, the relative CL intensity was linear with the concentration of HQ ranging from 6.0×10^-10 to 1.0×10 ^-8 g/mL. The detection limit, at the signal-to-noise ratio of 3 (3σ), was 1.0×10^-10 g/mL. The relative standard deviation (RSD) for 2.0×10^-9 g/mL HQ was 2.7% (n=11). The presented CL methodology has been applied for the determination of HQ in water samples with satisfactory results.