A novel mesoporous fluorescent molecularly imprinted sensor for selective detection of bisphenol A (BPA) in food materials was fabricated via a semi-covalent imprinting method. The imprinting precursor that served as an alternative template molecule for BPA was prepared via thermally reversible isocyanate bonding, which effectively improved the imprinting efficiency for the molecularly imprinted sensor. Carbon dots (CDs) were embedded in mesoporous silica as signal recognition elements that exhibited quenching upon BPA binding. Subsequently, through the sol–gel process, the molecularly imprinted layer was coated on the CDs silica layer and provided specific recognition sites for BPA. The composite of CDs embedded in the mesoporous molecularly imprinted polymer (CDs@MIP) was characterized with scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, Brunauer–Emmett–Teller measurements and thermogravimetric analysis. The mechanism of carbon dots quenching and the high selectivity of CDs@MIP towards BPA were explored. The linear response range of the sensor was from 0.025 mg L⁻¹ to 2 mg L⁻¹ with a limit of detection of 0.016 mg L⁻¹. The method was successfully applied for the determination of food samples and recoveries ranged from 92.5% to 101.1%. The BPA contents in actual samples were determined using high performance liquid chromatography and the proposed sensor, showing no significant difference between the two methods.

中文翻译：

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半共价分子印迹荧光传感器，用于双酚A的高度特异性识别和感光

通过半共价压印法制备了一种新型的介孔荧光分子印迹传感器，用于选择性检测食品中的双酚A（BPA）。压印前体充当了BPA替代模板分子来制备通过热可逆的异氰酸酯键，有效提高了分子印迹传感器的印迹效率。碳点（CD）嵌入在介孔二氧化硅中，作为信号识别元素，在BPA结合时表现出猝灭作用。随后，通过溶胶-凝胶工艺，将分子印迹层涂覆在CD二氧化硅层上，并为BPA提供特定的识别位点。通过扫描电子显微镜，透射电子显微镜，傅里叶变换红外光谱，Brunauer-Emmett-Teller测量和热重分析，对嵌入到介孔分子印迹聚合物（CDs @ MIP）中的CD复合材料进行了表征。探索了碳点猝灭的机理和CDs @ MIP对BPA的高选择性。传感器的线性响应范围从0开始。^-1至2 mg L ^-1，检出限为0.016 mg L ^-1。该方法成功地用于食品样品的测定，回收率在92.5％至101.1％之间。使用高效液相色谱法和拟议的传感器测定实际样品中的BPA含量，显示两种方法之间无显着差异。