Specifically and Visually Detect Methyl-Mercury and Ethyl-Mercury in Fish Sample Based on DNA-Templated Alloy Ag-Au Nanoparticles
Specifically and Visually Detect Methyl-Mercury and Ethyl-Mercury in Fish Sample Based on DNA-Templated Alloy Ag-Au Nanoparticles
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基于 DNA 模板化合金银金纳米颗粒特异性、直观地检测鱼样品中的甲基汞和乙基汞
DOI：
10.1021/acs.analchem.8b01100
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发表时间：
2018-04-17
影响因子：
7.4
通讯作者：
Fu, FengFu
中科院分区：
文献类型：
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作者：
Chen, Zhiqiang;Wang, Xusheng;Fu, FengFu
甲基汞（CH3Hg+）和乙基汞（C2H5Hg+）的毒性比Hg2+高得多，并且更容易被生物体积累，形成严重的生物放大作用。因此，对海鲜中CH3Hg+和C2H5Hg+进行特异性现场检测具有重要意义和艰巨的挑战。我们在此设计了两个富含T的适体（H-T5和H-T7），分别用于特异性识别CH3Hg+以及CH3Hg+和C2H5Hg+的总和。在所有 Au3+、Ag+ 和富含 T 适配体存在的情况下，CH3Hg+ 和 C2H5Hg+ 特异性且优先地与适配体结合，从而诱导还原后形成合金 Ag-Au 纳米粒子，从而导致溶液颜色变化。这为无仪器视觉辨别和检测CH3Hg+和C2H5Hg+提供了传感平台。该方法以H-T5为探针，肉眼观察可检测低至5.0μM（相当于1.0μg Hg/g）的CH3Hg+，紫外-可见光谱法可检测低至0.5μM（相当于100ng Hg/g）的CH3Hg+。该方法以H-T7为探针，可检测CH3Hg+和C2H5Hg+的总浓度，目视检出限为5.0μM（相当于1.0μg Hg/g），紫外可见光谱检出限为0.6μM（相当于120ng Hg/g）。该方法已成功用于检测鱼肌肉样品中的 CH3Hg+ 和 C2H5Hg+，回收率为 101-109%，RSD (n = 6) < 8%。这项研究的成功为仅通过肉眼观察来特异性现场检测海鲜中的CH3Hg+和C2H5Hg+提供了一种潜在的方法。
Methyl-mercury (CH3Hg+) and ethyl-mercury (C2H5Hg+) have much higher toxicity than Hg2+ and can be more easily accumulated by organisms to form severe bioamplification. Hence, the specific and on-site detection of CH3Hg+ and C2H5Hg+ in seafood is of great significance and a hard challenge. We herein designed two T-rich aptamers (H-T5 and H-T7) for specifically recognizing CH3Hg+ and the total of CH3Hg+ and C2H5Hg+, respectively. In the presence of all Au3+, Ag+, and T-rich aptamer, CH3Hg+ and C2H5Hg+ specifically and preferentially bind with aptamer and thus induced the formation of alloy Ag-Au nanoparticles after reduction, which led to the color change in solution. This provided a sensing platform for the instrument-free visual discrimination and detection of CH3Hg+ and C2H5Hg+. By using H-T5 as probe, the method can be used to detect as low as 5.0 mu M (equivalent to 1.0 mu g Hg/g) of CH3Hg+ by bare eye observation and 0.5 mu M (equivalent to 100 ng Hg/g) of CH3Hg+ by UV-visible spectrometry. By using H-T7 as probe, the method can be used to detect the total concentration of CH3Hg+ and C2H5Hg+ with a visual detection limit of 5.0 mu M (equivalent to 1.0 mu g Hg/g) and a UV-visible spectrometry detection limit of 0.6 mu M (equivalent to 120 ng Hg/g). The proposed method has been successfully used to detect CH3Hg+ and C2H5Hg+ in fish muscle samples with a recovery of 101-109% and a RSD (n = 6) < 8%. The success of this study provided a potential method for the specific and on-site detection of CH3Hg+ and C2H5Hg+ in seafood by only bare eye observation.