Key Laboratory of Land Resources Evaluation and Monitoring in Southwest, Ministry of Education, College of Chemistry and Material Science, Sichuan Normal University, Chengdu, Sichuan 610068, China.
State Key Laboratory of Southwestern Chinese Medicine Resources, School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu 611137, China.
Sci Total Environ. 2024 Dec 1;954:176416. doi: 10.1016/j.scitotenv.2024.176416. Epub 2024 Sep 19.
Developing rapid and sensitive methods for monitoring inorganic mercury (Hg) and methylmercury (CHHg) in crayfish is crucial for understanding the environmental impact of these contaminants. In this work, a novel tri-mode strategy was developed for highly sensitive monitoring of Hg and CHHg bioaccumulation in crayfish by inductively coupled plasma mass spectrometry (ICP-MS)/ fluorescence /smartphone colorimetric (RGB) analysis without chromatographic separation. Cation exchange reaction (CER) was performed between Hg and luminescent CdTe quantum dots (QDs), while CHHg unrealizable CER. The CHHg can be transformed to Hg by simple UV irradiation, speciation analysis can be realized by detecting the fluorescence of CdTe QDs after incubation by Hg and total Hg. In addition, the filtration of reacted CdTe QDs was carried out, ICP-MS was performed to detect exchanged Cd by Hg and total Hg, as well the smartphone RGB analysis was performed for membrane colorimetry. The limits of detection (LODs) of Hg and CHHg for ICP-MS, fluorescence, and colorimetric (RGB) modes were 0.03 ng mL, 18 ng mL, and 0.9 μg mL respectively. Density Functional Theory (DFT) was employed to validate the mechanism of the CER reaction. CdTe QDs array analysis with five different ligands was performed to eliminate potential ion interferences of Ag and Cu that could occur during the CER reaction. The well-designed system was successfully utilized for monitoring trace Hg and CHHg in crayfish fed Hg and CHHg contaminative food over a two-week "uptake" period and a three-week "depuration" period. The results indicated that the Hg uptake in different tissues was significantly different from that of CHHg in all tissues. There was evidence of Hg uptake from water via leaching from food, although the principal source of uptake was from food.
开发快速、灵敏的方法来监测水生生物体内的无机汞（Hg）和甲基汞（CHHg）对于了解这些污染物的环境影响至关重要。在这项工作中，开发了一种新颖的三模式策略，通过电感耦合等离子体质谱（ICP-MS）/荧光/智能手机比色（RGB）分析，无需色谱分离，对螯合反应（CER）前后的 Hg 和 CHHg 进行高灵敏度监测。Hg 与发荧光的 CdTe 量子点（QDs）发生 CER，而 CHHg 不能发生 CER。简单的紫外辐照可将 CHHg 转化为 Hg，孵育后通过检测 CdTe QDs 的荧光可进行 Hg 和总 Hg 的形态分析。此外，进行了反应后的 CdTe QDs 的过滤，通过 ICP-MS 检测 Hg 交换的 Cd 和总 Hg，以及智能手机 RGB 分析进行膜比色。ICP-MS、荧光和比色（RGB）模式下 Hg 和 CHHg 的检出限（LOD）分别为 0.03 ng mL、18 ng mL 和 0.9 μg mL。密度泛函理论（DFT）被用于验证 CER 反应的机制。通过 CdTe QDs 与五种不同配体的阵列分析，消除了在 CER 反应中可能发生的 Ag 和 Cu 的潜在离子干扰。该设计良好的系统成功用于监测两周“摄入”期和三周“净化”期内喂食 Hg 和 CHHg 污染食物的螯合生物体内痕量 Hg 和 CHHg。结果表明，不同组织中 Hg 的摄取与所有组织中 CHHg 的摄取有显著差异。有证据表明，Hg 是通过从食物中浸出从水中摄取的，尽管摄取的主要来源是食物。
