Key Laboratory of Luminescent and Real-Time Analytical Chemistry, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, PR China.
Chongqing Fiber Inspection Bureau, Chongqing 401121, PR China.
Talanta. 2019 Mar 1;194:1-6. doi: 10.1016/j.talanta.2018.09.106. Epub 2018 Oct 9.
A photoluminescence (PL) sensor based on core-shell quantum dots (QDs) coated with molecularly-imprinted polymer (MIP) shell was designed for the determination of perfluorooctanoic acid (PFOA) in water. PFOA is a persistent and bioaccumulating water contaminant whose detection is of great importance for ensuring safe water supplies. We demonstrate a simple method to fabricate CdTe@CdS QDs and then encapsulate them with a molecularly-imprinted silica film in a one-pot sol-gel reaction. The final composite was created by anchoring the MIP layer on the CdTe@CdS QDs using 3-aminopropyltriethoxysilane (APTES) as functional monomer and tetraethoxysilane (TEOS) as crosslinker in the presence of aqueous ammonia. The combination of QDs and MIP showed stable photoluminescence and good selectivity. The PL of the MIP-coated QDs composite was efficiently quenched when PFOA molecules occupied the templated binding sites. The composite was applied to the detection of PFOA and exhibited a good linearity in range of 0.25-15.00 µmol/L with a detection limit of 25 nmol/L (~10 ppb by mass). The proposed method has been applied successfully for the determination of trace PFOA in environmental water samples and has demonstrated its robustness in the presence of other molecules and ions.
基于核壳量子点（QDs）的光致发光（PL）传感器，其表面涂有分子印迹聚合物（MIP）壳，用于测定水中的全氟辛酸（PFOA）。PFOA 是一种持久性和生物累积的水污染物，其检测对于确保安全的供水非常重要。我们展示了一种简单的方法来制备 CdTe@CdS QDs，然后在一锅溶胶-凝胶反应中将其封装在分子印迹的硅石膜中。最后，通过在氨水溶液中使用 3-氨丙基三乙氧基硅烷（APTES）作为功能单体和四乙氧基硅烷（TEOS）作为交联剂，将 MIP 层锚定在 CdTe@CdS QDs 上，从而制备出最终的复合材料。QDs 和 MIP 的结合表现出稳定的光致发光和良好的选择性。当 PFOA 分子占据模板结合位点时，MIP 涂覆的 QDs 复合材料的 PL 被有效猝灭。该复合材料已成功应用于 PFOA 的检测，在 0.25-15.00 µmol/L 的范围内表现出良好的线性关系，检测限为 25 nmol/L（按质量计约为 10 ppb）。该方法已成功应用于环境水样中痕量 PFOA 的测定，并在存在其他分子和离子的情况下表现出其稳健性。
