A flexible magnetic and fluorescent sensing for the recognition and detection of bisphenol A (BPA) based on a hybrid magnetic Fe₃O₄@silica nanoparticle@Mn:ZnS quantum dots@molecularly imprinted polymers nanoparticles (Fe₃O₄@SiO₂@QDs@MIPs NPs) has been designed. Because of the high selectivity of MIPs, the strong fluorescence property of Mn:ZnS QDs, good magnetism of Fe₃O₄ and good water solubility of SiO_2, the Fe₃O₄@SiO₂@QDs@MIPs NPs can effectively detect BPA effectively in human urine. In the presence of BPA, a new compound is produced via the amino group of Fe₃O₄@SiO₂@QDs@MIPs NPs and the hydroxyl group of BPA, the energy of the QDs is transferred to the compound, which led to fluorescence quenching. The relative fluorescence intensity has decreased linearly with the increasing of BPA concentration in the range 50 to 700 ng/mL and the detection limit is found to be 1.6 ng/mL. In addition, the sensor has shown a strong selectivity with an imprinting factor of 8.7 and distinguished selectivity is also exhibited to BPA over other possibly competing molecules. On the basis of the merits of the Fe₃O₄@SiO₂@QDs@MIPs NPs, the sensor can be applied to detect BPA in human urine sample successfully.

中文翻译：

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基于磁性Fe3O4 @ SiO2 @ QDs @ MIPs纳米粒子的双酚A灵敏和选择性荧光传感

基于混合磁性Fe ₃ O ₄ @二氧化硅纳米粒子@Mn：ZnS量子点@分子印迹聚合物纳米粒子（Fe ₃ O ₄ @SiO ₂ @QDs ）的用于识别和检测双酚A（BPA）的柔性磁和荧光传感@MIP NPs）。由于MIP的高选择性，Mn：ZnS QDs的强荧光特性，Fe ₃ O _4的良好磁性以及SiO _{2 ，} Fe ₃ O ₄ @SiO _2的良好水溶性@ QDs @ MIPs NP可以有效地检测人尿中的BPA。在双酚A的存在下，通过Fe ₃ O ₄ @SiO ₂ @ QDs @ MIPs NPs的氨基和双酚A的羟基生成新的化合物，量子点的能量转移到该化合物上，从而导致荧光淬火。在50至700 ng / mL范围内，相对荧光强度随BPA浓度的增加呈线性下降，并且检出限为1.6 ng / mL。此外，该传感器显示出了极高的选择性，印迹因子为8.7，并且对BPA的选择性也优于其他可能竞争的分子。基于Fe ₃ O ₄ @SiO ₂的优点@ QDs @ MIPs NPs，该传感器可用于成功检测人尿液样品中的BPA。