A Novel Chemiluminescent Probe for Effective Discrimination and Ultrasensitive Detection of Hydroquinone from Its Isomers Based on a Dihydroacridine Derivative

Abstract

The discovery of novel luminescent molecules could inject new vitality into the field of chemiluminescent (CL) techniques, including unexpected analytical performance, a unique detection mechanism, and promising applications. Herein, a superselective and sensitive CL probe based on a dihydroacridine derivative (i.e., CMDA) was developed for the first time to detect hydroquinone (HQ). In the design, CMDA was encapsulated into the micelles, which could improve the solubility of CMDA and provide a suitable microenvironment for the CL reaction of CMDA with HQ. Meanwhile, in a buffer solution rich in amino groups, HQ, with the strongest reducing property, could easily autoxidize to generate semiquinone radicals, which facilitated the generation of O2•– in the presence of oxygen. Furthermore, a disproportionation reaction of O2•– occurred, resulting in the formation of H2O2, which could react with CMDA to yield the excited ketone group with maximum emission wavelength at 440 nm. Notably, in comparison with commercial acridinium ester, the CMDA-based CL probe with stable and long-lasting CL emission exhibited a lower detection limit of 2.4 nM and a wider linear range of 0.02–1.00 μM. The proposed CL probe successfully detected HQ from different environmental scenarios with recoveries of 96.2–112.6%. Potentially, the proposed CL probe with high selectivity, outstanding sensitivity, excellent stability, and good reproducibility characteristics could not only offer a reliable method for HQ detection, but also enable the efficient detection of HQ in complex samples.