Improving sensitivity for microchip electrophoresis interfaced with inductively coupled plasma mass spectrometry using parallel multichannel separation

Abstract

We reported sensitivity enhancement using multichannel parallel separation for microchip electrophoresis hyphenated with inductively coupled plasma mass spectrometry (MCE-ICP-MS) in this study. By using 2-20 array lanes for parallel separation, the sensitivity of the MCE-ICP-MS system was proportionally improved by 2-20 folds. No significantly adverse effect of parallel separation on column efficiency and resolution was observed. Rapid separation of Hg2+ and methylmercuric (MeHg) ion within 36s under an electric field of 800Vcm−1 was achieved in the 2-cm twenty-channels with a background electrolyte of 5mmolL−1 borate buffer (pH 9.2). Detection limits of Hg2+ and MeHg by the proposed system were decreased to 6.8–7.1ngL−1. Good agreement between determined values and certified values of a certified reference fish was obtained with recoveries ranged between 94–98%. All results prove its advantages including high sensitivity, high efficiency and low operation cost, which are beneficial to routine analysis of metal speciation in environmental, biological and food fields.