Simultaneous measurements of Cr, Cd, Hg and Pb species in ng L−1 levels by interfacing high performance liquid chromatography and inductively coupled plasma mass spectrometry

• Published in: Analytica chimica acta 2022-06, Vol.1212, p.339935-339935, Article 339935
• Main Authors: Song, Yihuan, Guo, Feng, Zeng, Pingxiu, Liu, Jinhua, Wang, Yuanchao, Cheng, Heyong
• Format: Article
• Language: English
• Subjects: Cadmium - analysis; Chromatography, High Pressure Liquid - methods; Drinking Water - analysis; Heavy metals; HPLC-ICP-MS; Lead - analysis; Mass Spectrometry - methods; Mercury - analysis; Multi-elemental speciation; Online SPE; Water
• ISSN: 0003-2670; 1873-4324
• DOI: 10.1016/j.aca.2022.339935

Toxicity, mobility, bioavailability and biofunctions of chromium, cadmium, mercury and lead are heavily dependent upon their specific chemical forms, leading to a high demand to metal speciation analysis rather than total quantification. Simultaneous speciation analysis of multiple metal(loid)s is attractive to a large sample capacity containing unstable analytes due to its economic and environmental advantages over the conventional single elemental strategies. In this work, an analytical method integrating online solid phase extraction into high performance liquid chromatography interfaced with inductively coupled plasma mass spectrometry (ICP-MS) to simultaneously preconcentrate and quantify Cr, Cd, Hg and Pb forms in pg L−1 levels in water was developed. Cr(III + VI), Cd(II), Hg(II), Pb(II), methylmercury (MeHg), ethylmercury (EtHg), and trimethyl (TML) and triethyl lead (TEL) were captured by the C18 adsorbent (equilibrated with 10 mL of 1.0 mM 2-hydroxyethanethiol at 10 mL min−1) and eluted by mobile phase (5.0 mM Cys at pH 2.0), then completely separated on the C18 column within 8.0 min and eventually determined by ICP-MS. Low limits of detection (0.001–0.007 ng L−1) and quantification (0.003–0.023 ng L−1), good relative standard deviations (