CdSe/ZnS quantum dots based fluorescence quenching method for determination of paeonol

Aqueous polymethylmethacrylate (PMMA)-capped CdSe/ZnS quantum dots were used as fluorescence probes for paeonol determination. Based on the fluorescence quenching of aqueous CdSe/ZnS quantum dots caused by paeonol, a simple, sensitive and rapid method was developed. Under the optimal conditions, with excitation and emission wavelengths at 350 nm and 620 nm, respectively, the calibration plot of F-0 - F with concentration of paeonol was linear in the range of 25.04-175.2 mg L-1 with correlation coefficient of 0.9986. The limit of detection was 0.017 mg L-1. The concentration of paeonol in paeonol ointment was determined by the proposed method and the result agreed with the claimed value. Furthermore, the possible fluorescence quenching mechanism was discussed. (C) 2010 Elsevier B.V. All rights reserved.