College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, PR China; Key Laboratory of Hunan Province for Water Environment and Agriculture Product Safety, Central South University, Changsha 410083, PR China.
College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, PR China.
Talanta. 2019 May 1;196:579-584. doi: 10.1016/j.talanta.2019.01.007. Epub 2019 Jan 3.
A facile and sensitive fluorescent sensor based on coating molecularly imprinted polymers onto the surface of CdTe quantum dots (CdTe-QDs@MIPs) was successfully fabricated for selective determination of p-coumaric acid (pCA) for the first time by the strategy of charge transfer principle. MIPs layer was synthesized by one-pot sol-gel reaction using 3-(aminopropyl) triethoxysilane (APTES) as functional monomer and tetraethyl orthosilicate (TEOS) as crosslinker. Controllable particle size of CdTe-QDs@MIPs was formed by simply adjusting the polymerization time. Smaller particle size (about 56 nm) at polymerization time of 5 min reduced embedded sites, and then resulted in fast response (within only 4 min), and high sensitivity (limit of detection, LOD low to 6.74 μg L) for pCA. Different parameters during synthesis and determination procedures affecting the fluorescent probe were optimized. The fluorescent intensity of CdTe-QDs@MIPs was remarkably quenched by pCA compared to CdTe-QDs@NIPs with an imprinting factor of 27.0. Finally, the fluorescence quenching analysis showed excellent linear ranges from 20 to 1000 μg L (R, 0.9964) with distinguished selectivity, and batch-to-batch relative standard deviation (RSD) was 3.8%. The proposed method was applied successfully for the determination of pCA in pineapple juice and kiwi juice with satisfactory recoveries from 92.7% to 106.0%, and precisions below 8.1%. The proposed fluorescent sensor exhibited simple and rapid preparation and detection procedures, high sensitivity and excellent selectivity. It is envisioned that the resultant CdTe-QDs@MIPs offered a new way of rapid and sensitive analysis of pCA in real complex samples.
一种基于在 CdTe 量子点（CdTe-QDs）表面涂覆分子印迹聚合物（MIPs）的简便灵敏荧光传感器，首次通过电荷转移原理策略成功制备，用于选择性测定对香豆酸（pCA）。MIPs 层通过一锅溶胶-凝胶反应合成，使用 3-（氨丙基）三乙氧基硅烷（APTES）作为功能单体和正硅酸乙酯（TEOS）作为交联剂。通过简单地调整聚合时间，可以形成可控粒径的 CdTe-QDs@MIPs。聚合时间为 5 分钟时，粒径较小（约 56nm），减少了嵌入位点，从而导致快速响应（仅需 4 分钟）和高灵敏度（检测限，LOD 低至 6.74μg/L）pCA。优化了合成和测定过程中影响荧光探针的不同参数。与 CdTe-QDs@NIPs 相比，pCA 显著猝灭了 CdTe-QDs@MIPs 的荧光强度，印迹因子为 27.0。最后，荧光猝灭分析显示，在 20 至 1000μg/L 的范围内具有出色的线性范围（R，0.9964），具有明显的选择性，批间相对标准偏差（RSD）为 3.8%。该方法成功应用于菠萝汁和猕猴桃汁中 pCA 的测定，回收率为 92.7%至 106.0%，精密度低于 8.1%。所提出的荧光传感器具有简单快速的制备和检测程序、高灵敏度和优异的选择性。预计所得的 CdTe-QDs@MIPs 为快速灵敏分析实际复杂样品中的 pCA 提供了一种新方法。
