Study on capillary electrophoresis enrichment and separation system based on field magnified injection-electric counter balance purge-trap and its application in iron ore detection
ZHANG Xiao-wei
School of Science, Qingdao Technological University, Qingdao 266033, China
Abstract：Combining with field magnified injection technology, the determination of six heavy metal elements (manganese, chromium, lead, copper, nickel and cobalt) in iron ore by on-line dual-enrichment capillary electrophoresis enrichment and separation system based on field magnified injection-electric counter balance purge-trap was established using EDTA as trap carrier. The metal ions were firstly accumulated on the interface between water plug and high-conductivity buffer solution via field magnified injection, and then trapped by oncoming negative charged EDTA. The sample region was further compressed, realizing the dual amplification of signal. By controlling the electro-osmotic flow, the metal-EDTA chelate was under quasi-static condition. Thus, the large volume injection and significant amplification of detection signal were realized. After dual-enrichment at 15 kV for 50 min, the sensitivity increased by 1.2×104-8.5×104 times than that of conventional capillary electrophoresis. The detection limits of six heavy metal ions in iron ore were 0.06-0.32 μg/L. The proposed method was applied to the determination of manganese, chromium, lead, copper, nickel and cobalt in iron ore. The relative error between determination results of proposed method and those of ICP-MS was between 5.3 %-11.5 %.
张效伟. 基于场放大进样-电动反平衡扫集的毛细管电泳富集分离系统的研究及其在铁矿石检测中的应用[J]. 冶金分析, 2013, 33(8): 1-5.
ZHANG Xiao-wei. Study on capillary electrophoresis enrichment and separation system based on field magnified injection-electric counter balance purge-trap and its application in iron ore detection. , 2013, 33(8): 1-5.
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