SPECIATION OF ORGANOMERCURIALS BY CAPILLARY ELECTROPHORESIS WITH PRE-COLUMN UV DERIVATIZATION AND ON-LINE CONCENTRATION

摘要

Simultaneous separation and detection of methylmercury (MeHg), ethylmercury (EtHg) and phenylmercury (PhHg) was investigated by capillary electrophoresis with UV detection using thiosalicylic acid as derivatization reagent. The separation parameters such as buffer pH, ion strength were investigated. A baseline separation was obtained by using 30 mmol L-1 of borate as buffer at pH 9.2. Then an on-line concentration method was used to improve the detection sensitivity. Parameters such as concentration of NaCl in sample matrix and injection time were optimized. The limits of detection were 76.9, 83.0 and 76.4 μg L-1 for PhHg, EtHg and MeHg, respectively.