College of Material Chemistry and Chemical Engineering, Hangzhou Normal University, Hangzhou 311121, China; Key Laboratory of Organosilicon Chemistry and Material Technology, Hangzhou Normal University, Hangzhou 311121, China.
College of Material Chemistry and Chemical Engineering, Hangzhou Normal University, Hangzhou 311121, China.
J Chromatogr A. 2018 Nov 9;1575:59-65. doi: 10.1016/j.chroma.2018.09.023. Epub 2018 Sep 17.
Metal speciation analysis of microsamples in the clinical, biological and forensic fields is important for elucidating the metals' toxicity, mobility and metabolic behaviors of metals. Such analysis may be achieved by nanoliter high-performance liquid chromatography (nanoHPLC) hyphenated with inductively coupled plasma mass spectrometry (ICP-MS). In this work, an in-column high-pressure nebulizer (ICHPN) was developed to enhance the sensitivity and the separation efficiency of the sheathless nanoHPLC-ICP-MS coupling. The ICHPN consists of two concentric fused-silica capillaries with tapered tips connected via a PEEK tee, where C silica particles with a size of 5 μm were packed in the tapered inner capillary based on the keystone effect. Combining a heated single pass spray chamber with a makeup gas, the ICHPN was capable of independently optimizing the nebulization efficiency and the transport efficiency. The ICHPN offered high sensitivities, low detection limits and good precision at nanoflow rates. Compared with commercial nebulizers, the ICHPN fabrication was simple, rapid, reproducible and inexpensive. By implementing the ICHPN, we achieved rapid separation of four mercury species, i.e., Hg and methyl-, ethyl- and phenylmercuric chloride, within 8.0 min with good resolution (2.0-13.9). Detection limits of 0.044-0.13 μg L were obtained with precisions of peak heights and areas ranging from 1.5 to 3.5% for a 50 μg L standard solution. Good agreement between the determined and certified values of mercury species in a certified reference material of caprine blood (SRM 955c) together with good recoveries (93-101%) validated the accuracy of the method.
用于阐明金属的毒性、迁移性和代谢行为，对临床、生物和法医领域中的微样本进行金属形态分析非常重要。这种分析可以通过纳升高效液相色谱（nanoHPLC）与电感耦合等离子体质谱（ICP-MS）联用实现。在本工作中，开发了一种柱内高压雾化器（ICHPN），以提高无鞘 nanoHPLC-ICP-MS 联用的灵敏度和分离效率。ICHPN 由两个带有锥形尖端的同心熔融石英毛细管组成，通过 PEEK 三通连接，在锥形内毛细管中填充了尺寸为 5 μm 的 C 硅胶颗粒，基于尖顶石效应。结合加热的单通道喷雾室和补充气体，ICHPN 能够独立优化雾化效率和传输效率。ICHPN 在纳流率下提供了高灵敏度、低检测限和良好的精密度。与商业雾化器相比，ICHPN 的制造简单、快速、可重复且成本低廉。通过实施 ICHPN，我们在 8.0 min 内实现了四种汞形态（即 Hg 和甲基、乙基和苯基氯化汞）的快速分离，具有良好的分辨率（2.0-13.9）。对于 50 μg L 标准溶液，获得了 0.044-0.13 μg L 的检测限，峰高和峰面积的精密度在 1.5-3.5%范围内。在山羊血标准参考物质（SRM 955c）中，汞形态的测定值与认证值之间以及良好的回收率（93-101%）非常吻合，验证了该方法的准确性。
