Chen Zu Liang, Lin Jin-Ming, Naidu Ravendra
Adelaide Laboratory, CSIRO Land and Water, PMB2, 5064 Glen Osmond, SA, Australia.
Anal Bioanal Chem. 2003 Mar;375(5):679-84. doi: 10.1007/s00216-003-1777-5. Epub 2003 Feb 18.
A simple capillary zone electrophoresis procedure was developed for the separation of arsenic species (AsO(2)(2-), AsO(4)(2-), and dimethylarsinic acid, DMA). Both counter-electroosmotic and co-electroosmotic (EOF) modes were investigated for the separation of arsenic species with direct UV detection at 185 nm using 20 mmol L(-1) sodium phosphate as the electrolyte. The separation selectivity mainly depends on the separation modes and electrolyte pH. Inorganic anions (Cl(-), NO(2)(-), NO(3)(-) and SO(4)(2-)) presented in real samples did not interfere with arsenic speciation in either separation mode. To improve the detection limits, sample-stacking techniques, including large-volume sample stacking (LVSS) and field-amplified sample injection (FASI), were investigated for the preconcentration of As species in co-CZE mode. Less than 1 micromol L(-1) of detection limits for As species were achieved using FASI. The proposed method was demonstrated for the separation and detection of As species in water.
开发了一种简单的毛细管区带电泳方法用于分离砷的各种形态（亚砷酸根离子AsO₂²⁻、砷酸根离子AsO₄²⁻和二甲基砷酸DMA）。研究了反电渗和共电渗（电渗流，EOF）模式，以20 mmol L⁻¹磷酸钠为电解质，在185 nm处采用直接紫外检测法分离砷的各种形态。分离选择性主要取决于分离模式和电解质pH值。实际样品中存在的无机阴离子（Cl⁻、NO₂⁻、NO₃⁻和SO₄²⁻）在两种分离模式下均不干扰砷的形态分析。为了提高检测限，研究了样品堆积技术，包括大体积样品堆积（LVSS）和场放大进样（FASI），用于在共毛细管区带电泳模式下对砷形态进行预富集。采用FASI实现了砷形态低于1 μmol L⁻¹的检测限。该方法用于水中砷形态的分离和检测。
