State Key Laboratory of Separation Membranes and Membrane Processes/National Center for International Joint Research on Separation Membranes, School of Chemistry and Chemical Engineering, Tiangong University, Tianjin, 300387, People's Republic of China.
Mikrochim Acta. 2020 May 23;187(6):344. doi: 10.1007/s00604-020-04318-3.
Based on WS quantum dots (QDs) as fluorescent signals and MnO nanosheets as second-order scattering (SOS) signals, a combination of fluorescence and scattered light was used to construct a ratio sensing platform for glutathione (GSH) detection. When MnO nanosheets are added to WS QDs, the fluorescence of WS QDs is quenched by MnO nanosheets through IFE. Large-sized MnO nanosheets increase the SOS of the system and gradually approach the fluorescence. After adding GSH to WS QDs-MnO, the MnO nanosheets were decomposed into Mn. The disappearance of the characteristic absorption peak of the MnO nanosheets suppressed the IFE to WS QDs, resulting in the fluorescence recovery of WS QDs. The reduction in size of MnO nanosheets after decomposition results in a decrease in the SOS of the system. Therefore, the ratio detection of GSH is obtained through the fluorescence and SOS dual signal response. Under optimal experimental conditions, the value of F/S is linearly related to the GSH concentration in the range 0 to 60 μM, and the limit of detection (LOD) of GSH is 0.12 μM. In addition, the system is also used for the determination of GSH in real water samples and human serum, with good analytical results. Graphical abstract Schematic principle of fluorescence/scattered light system based on WS QDs-MnO for GSH ratiometric detection.
基于 WS 量子点 (QD) 作为荧光信号和 MnO 纳米片作为二次散射 (SOS) 信号，结合荧光和散射光构建了用于谷胱甘肽 (GSH) 检测的比率传感平台。当 MnO 纳米片添加到 WS QD 时，MnO 纳米片通过内滤效应 (IFE) 猝灭 WS QD 的荧光。大尺寸的 MnO 纳米片增加了系统的 SOS，并逐渐接近荧光。向 WS QD-MnO 中加入 GSH 后，MnO 纳米片分解为 Mn。MnO 纳米片特征吸收峰的消失抑制了对 WS QD 的 IFE，导致 WS QD 的荧光恢复。分解后 MnO 纳米片的尺寸减小导致系统 SOS 降低。因此，通过荧光和 SOS 双重信号响应实现了 GSH 的比率检测。在最佳实验条件下，F/S 值与 0 至 60 μM 范围内 GSH 浓度呈线性关系，GSH 的检测限 (LOD) 为 0.12 μM。此外，该系统还用于实际水样和人血清中 GSH 的测定，具有良好的分析结果。
