Chemiluminescence resonance energy transfer between CdS quantum dots and lucigenin and its sensing application

Weak chemiluminescence (CL) of lucigenin was obtained in alkaline solution in the absence of H2O2, which could be apparently enhanced in the presence of CdS, CdSe, and CdTe quantum dots (QDs), and the most intense CL signal was obtained in the CdS QDs involved CL system. The CL spectrum revealed that the light emitter of lucigenin/CdS CL system is the excited state of CdS QDs. The overlap of the lucigenin CL spectrum and the UV–vis absorption spectrum of CdS QDs suggested that CL resonance energy transfer (CRET) could occur between them. The excited state of lucigenin can act as energy donor, and transfer its energy to CdS QDs, resulting in the strong CL emission. Ascorbic acid (AA) could further increase CL intensity, and the increased CL intensities were proportional to the concentrations of AA in the range of 1.0×10−10 mol L−1 to 5.0×10−6 mol L−1 with the detection limit of 6.7×10–11 mol L−1. The proposed CRET system could be successfully applied in the sensitive detection of the level of AA in juice samples.