Wu Ning, Guo Hao, Wang Mingyue, Peng Liping, Chen Yuan, Liu Bingqing, Pan Zhilan, Liu Yinsheng, Yang Wu
College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070, PR China.
College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070, PR China.
Spectrochim Acta A Mol Biomol Spectrosc. 2022 Apr 5;270:120858. doi: 10.1016/j.saa.2022.120858. Epub 2022 Jan 5.
Ratio fluorescence has attracted much attention because of its self-calibration properties. However, it is difficult to obtain suitable fluorescent materials with well-resolved signals simultaneously under one excitation. In this work, we report a different strategy, using MIL-68(In)-NH as both the fluorescence element and the scattered light unit, and coupling the fluorescence and the scattered light to construct the fluorescence and scattered light ratio system. Based on the optical properties and the second-order scattering (SOS) of the material nanoparticles, the synthesized MIL-68(In)-NH can be used to realize the ratio detection of Hg. Because the scattering intensity of small particle MIL-68(In)-NH is weak, SOS is not obvious. When Hg is introduced the coordination reaction between the amino nitrogen atoms of MIL-68(In)-NH and Hg make the particles larger, resulting in the decrease of fluorescence and the enhancement of SOS. As a result, a novel Hg ratiometric detection method is developed by using the dual signal responses of the fluorescence and scattering. Under the optimal conditions (pH = 6, reaction time 5 min, room temperature, and the maximum excitation wavelength 365 nm), the linear range of the method is 0-100 μM, and the detection limit is 5.8 nM (Ksv = 9.89 × 10 M). In addition, the probe is successfully used to evaluate Hg in actual water samples. Compared with the traditional method of recording only the fluorescence signal, the proposed fluorescence-scattering method provides a new strategy for the design of ratiometric sensors.
比率荧光因其自校准特性而备受关注。然而，在单一激发下同时获得具有良好分辨信号的合适荧光材料却很困难。在这项工作中，我们报道了一种不同的策略，使用MIL-68(In)-NH作为荧光元素和散射光单元，并将荧光和散射光耦合以构建荧光与散射光比率系统。基于该材料纳米颗粒的光学性质和二次散射（SOS），合成的MIL-68(In)-NH可用于实现汞的比率检测。由于小颗粒MIL-68(In)-NH的散射强度较弱，SOS不明显。当引入汞时，MIL-68(In)-NH的氨基氮原子与汞之间的配位反应使颗粒变大，导致荧光减弱和SOS增强。结果，利用荧光和散射的双重信号响应开发了一种新型汞比率检测方法。在最佳条件下（pH = 6，反应时间5分钟，室温，最大激发波长365 nm），该方法的线性范围为0 - 100 μM，检测限为5.8 nM（Ksv = 9.89 × 10 M）。此外，该探针成功用于评估实际水样中的汞。与仅记录荧光信号的传统方法相比，所提出的荧光 - 散射方法为比率传感器的设计提供了一种新策略。
