A chemiluminescence resonance energy transfer system composed of cobalt(II), luminol, hydrogen peroxide and CdTe quantum dots for highly sensitive determination of hydroquinone

This article describes a nonenzymatic chemiluminescence resonance energy transfer (CRET) system for highly sensitive determination of hydroquinone. It was found that the Co(II)-catalyzed luminescence of luminol in pH 11.5 solution is transferred to CdTe quantum dots (QDs) via a CRET mechanism. Hydroquinone is oxidized by H 2 O 2 to benzoquinone which quenches the fluorescence of the QDs. The enhancement is attributed to the adsorption of Co(II) on the surface of the negatively charged QDs. The CRET system was applied in an assay for hydroquinone that has a detection limit of 0.17 nmol L −1 . The detection limit was lower by factors between 100 and 250,000 than earlier reported methods. The assay was successfully applied to the quantitation of hydroquinone in (spiked) water samples, with recoveries ranging from 95 % to 106 %, and relative standard deviations between 0.5 % and 2.4 %. A Co(II)-luminol-H 2 O 2 -quantum dot chemiluminescence resonance energy transfer system was developed for highly sensitive detection of hydroquinone. Strong signals were observed due to energy transfer between luminol donor and CdTe quantum dots which is catalyzed by Co(II).