一种改进的方法,用于快速和安全的制备和测量二甲基,使用气相色谱-原子光谱法
Yingying Chen1, Qingzhe Zhang1, Lian Zhang1
1Shandong Key Laboratory of Environmental Processes and Health, Qingdao Key Laboratory of Marine Pollutant Prevention, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China.
Journal of chromatography. A
|November 4, 2023
概括
开发了一种新的,安全的二甲基 (DMHg) 生产器和测量方法,以解决 (Hg) 循环中的知识差距. 这允许在水样中精确量化DMHg.
科学领域:
- 环境化学环境化学
- 生物地质化学生物地质化学
- 分析化学 分析化学
背景情况:
- (Hg) 物种,特别是二甲基 (DMHg) 的转化在全球Hg生态化学循环中被了解得很少.
- DMHg的高毒性和挥发性对其制备和测量构成重大挑战.
- 现有的方法缺乏对DMHg进行详细研究所需的安全性和控制.
研究的目的:
- 开发一种新,安全和可控制的方法来制备高纯度二甲基 (DMHg).
- 建立一种敏感且可靠的分析方法,用于在水样中量化DMHg.
- 在环境分析中克服与DMHg的毒性和波动性相关的挑战.
主要方法:
- 发明了一种新的DMHg发生器,使其能够自发地挥发和扩散,以确保安全的制备.
- 优化的DMHg生成参数:pH值为4.0,MeCo/Hg2+摩尔比为10,温度为20°C.
- 开发并优化了一种气相色谱方法,以分离DMHg与其他Hg物种 (例如Hg0,单甲) 以特定的流量和柱体温度.
主要成果:
- 在最佳条件下使用新型发电机成功制备了高纯度的DMHg.
- 使用15mL min-1的载体气体流量率和30°C的柱体温度,实现了Hg0和DMHg的有效分离.
- 开发了一种检测极限较低的方法 (Hg0:0.03 ng L-1,MMHg:0.002 ng L-1,DMHg:0.024 ng L-1),相对标准偏差低于8.2%.
- 使用自然水样验证了该方法,证明了其可靠性用于微量DMHg的确定.
结论:
- 开发的DMHg发生器为制备这种有毒化合物提供了安全可控的策略.
- 优化的分析方法可以在环境矩阵中对DMHg进行敏感且可靠的量化.
- 这项工作通过为DMHg研究提供必要的工具,大大推进了对生物地质化学的研究.
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