Research Center for Natural Medicine and Chemical Metrology, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China; University of Chinese Academy of Sciences, Beijing 100049, China.
Research Center for Natural Medicine and Chemical Metrology, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China.
Spectrochim Acta A Mol Biomol Spectrosc. 2025 Jan 15;325:125071. doi: 10.1016/j.saa.2024.125071. Epub 2024 Aug 31.
In this paper, a novel ratiometric fluorescent probe based on silicon quantum dots (SiQDs) has been developed for the sensitive detection of methyl parathion pesticide residues. The silicon quantum dots were prepared by a simple hydrothermal reaction process using 3-Aminopropyltriethoxysilane (APTES) as silicon resource and were characterized by the analysis of transmission electron microscopy, FTIR spectroscopy, and X-ray photoelectron spectroscopy. The silicon quantum dots displayed characteristic blue fluorescence emission at 440 nm. Tyrosinase can catalyze the oxidation of tyramine to form dopamine. Then, dopamine can interact with silicon quantum dots and effectively change the position of its fluorescence emission for redshifting to 540 nm. In the presence of organic phosphorus pesticides (OPPs), the activity of tyrosinase was inhibited, resulting in the inability to generate dopamine and the fluorescence emission at 440 nm remaining unchanged. As a model of organic phosphorus pesticides, methyl parathion (MP) was determined using this method, and the fluorescence intensity response values showed a good linear relationship with methyl parathion concentration in the range of 50-90 nM, with a detection limit of 0.149 nM. Due to its good performance of relative low detection limit, good selectivity and high reproducibility, this sensing system has been successfully applied to the detection of methyl parathion in environmental water samples and potato samples, which showed good prospects for application in the detection of organic phosphorus pesticide residues in more real samples.
本文报道了一种基于硅量子点（SiQDs）的新型比率荧光探针，用于灵敏检测甲基对硫磷农药残留。硅量子点通过简单的水热反应过程制备，使用 3-氨丙基三乙氧基硅烷（APTES）作为硅源，并通过透射电子显微镜、傅里叶变换红外光谱和 X 射线光电子能谱进行了分析。硅量子点在 440nm 处显示出特征的蓝色荧光发射。酪氨酸酶可以催化酪胺的氧化生成多巴胺。然后，多巴胺可以与硅量子点相互作用，并有效地改变其荧光发射位置，发生红移至 540nm。在有机磷农药（OPPs）存在下，酪氨酸酶的活性受到抑制，导致无法生成多巴胺，而 440nm 处的荧光发射保持不变。以甲基对硫磷（MP）作为有机磷农药的模型，采用该方法进行了测定，荧光强度响应值与甲基对硫磷浓度在 50-90nM 范围内呈现良好的线性关系，检测限为 0.149nM。由于其具有相对低的检测限、良好的选择性和高重现性等优异性能，该传感系统已成功应用于环境水样和土豆样品中甲基对硫磷的检测，在更真实的样品中检测有机磷农药残留方面具有良好的应用前景。
