Assi Navid, Rypar Tomas, Macka Mirek, Adam Vojtech, Vaculovicova Marketa
Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, CZ 613 00, Brno, Czech Republic.
Central European Institute of Technology, Brno University of Technology, Purkynova 123, CZ-612 00, Brno, Czech Republic.
Talanta. 2023 Apr 1;255:124185. doi: 10.1016/j.talanta.2022.124185. Epub 2023 Jan 6.
Microfluidic paper-based analytical devices modified with molecularly imprinted polymers (μPADs@MIPs) were developed for fluorescent detection of targeted thiols via in situ UV-induced formation of quantum dots (μPADs@MIPs@QDs). The selectivity enhancement by the MIP layer formed on the filter paper surface was demonstrated for the isolation of L-homocysteine from wine. Followed by the addition of metal precursors solution (Zn/Cd/Cu) and UV irradiation, fluorescent quantum dots were formed thus enabling quantitative detection of the thiol (serving as a QD capping agent). The effect of different semiconductors was investigated to achieve a lower band gap and higher fluorescence intensity. Increasing fluorescence intensity in the presence of thiol groups was obtained for the following precursors mixture composition: ZnCdCu/S > ZnCd/S > ZnCu/S > ZnS. The proposed method has a good relationship between the fluorescence intensity of ZnCdCu/S QDs and L-homocysteine in a linear range from 0.74 to 7.40 μM with a limit of detection (LOD) and quantification (LOQ) of 0.51 and 1.71 μM respectively. This method was applied for the determination of L-homocysteine in white wine with RSD under 6.37%.
开发了用分子印迹聚合物修饰的基于微流控纸的分析装置（μPADs@MIPs），用于通过原位紫外诱导量子点的形成（μPADs@MIPs@QDs）对目标硫醇进行荧光检测。通过在滤纸表面形成的MIP层提高选择性，证明了从葡萄酒中分离L-同型半胱氨酸的可行性。加入金属前驱体溶液（锌/镉/铜）并进行紫外照射后，形成荧光量子点，从而能够对硫醇进行定量检测（硫醇作为量子点封端剂）。研究了不同半导体的影响，以实现更低的带隙和更高的荧光强度。对于以下前驱体混合物组成，在存在硫醇基团的情况下荧光强度增加：ZnCdCu/S > ZnCd/S > ZnCu/S > ZnS。所提出的方法在0.74至7.40 μM的线性范围内，ZnCdCu/S量子点的荧光强度与L-同型半胱氨酸之间具有良好的关系，检测限（LOD）和定量限（LOQ）分别为0.51和1.71 μM。该方法用于测定白葡萄酒中的L-同型半胱氨酸，相对标准偏差（RSD）低于6.37%。
