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In the present study, a lanthanide fluorescence sensor array was developed for the discrimination of honey’s botanical origin. Dipicolinic acid (DPA) was used as the antenna ligand for sensitizing the fluorescence of Tb3+ and Eu3+ to prepare the DPA-Tb3+/Eu3+ complex. This lanthanide fluorescence sensor showed a cross-reactive response to the major constituents of honey, which led to the result that different classes of honey solution exhibited distinct quenching effects on the fluorescence of the DPA-Tb3+/Eu3+ complex. Furthermore, a fluorescence sensor array composed of ten sensors was constructed by adjusting the pH and the component of the DPA-Tb3+/Eu3+ complex to show multivariate responses towards honey. The visual fluorescence image of the sensor array was recorded by using a smartphone under excitation with portable UV lamp. Results indicated that the pattern of the visual image was related with the botanical origin. After extracting the RGB value of each sensor in 96-well plate, the ratio of R/G was used for principal component analysis (PCA). The results showed that three classes of honey (astragalus, logan, and litchi) were well distinguished. Moreover, the value of principal component 1 (PC1) showed good linearity with the composition of mixing honey and could be used for semi-quantitative analysis. The proposed lanthanide fluorescence sensor array presents a visual and portable method for the discrimination of a honey’s origin without the use of analytical instruments, and might provide a novel and simple strategy for the measurement of food origin.

In the present work, a novel sample preparation method, micro salting-out assisted matrix solid-phase dispersion (μ-SOA-MSPD), was developed for the determination of bisphenol A (BPA) and bisphenol B (BPB) contaminants in bee pollen. The proposed method was designed to combine two classical sample preparation methodologies, matrix solid-phase dispersion (MSPD) and homogenous liquid-liquid extraction (HLLE), to simplify and speed-up the preparation process. Parameters of μ-SOA-MSPD were systematically investigated, and results indicated the significant effect of salt and ACN-H2O extractant on the signal response of analytes. In addition, excellent clean-up ability in removing matrix components was observed when primary secondary amine (PSA) sorbent was introduced into the blending operation. The developed method was fully validated, and the limits of detection for BPA and BPB were 20 μg/kg and 30 μg/kg, respectively. Average recoveries and precisions were ranged from 83.03% to 94.64% and 1.76% to 5.45%, respectively. This is the first report on the analysis of bisphenol contaminants in bee pollen sample, and also on the combination of MSPD and HLLE. The present method might provide a new strategy for simple and fast sample preparation of solid and semi-solid samples.