Capillary electrophoresis-contactless conductivity detection – a tool for sample suitability testing in liquid chromatography-mass spectrometry separations

Abstract

High performance liquid chromatography coupled with mass spectrometry is a useful analytical technique, however it faces difficulties when separating biological and high inorganic content containing samples. In this case, special sample preparation with effective desalting procedure is needed. In this work capillary electrophoresis coupled with capacitance-to-digital based contactless conductivity detection was used for determination of inorganic cations in biological nisin containing samples. The procedure allows rapid separation and determination of inorganic cations in biological samples. Capillary electrophoresis separations before and after solid phase extraction – sample preparation of nisin containing samples indicate dramatic decrease of inorganic compounds, which allow further analysis using high performance liquid chromatography – mass spectrometry. Additionally, after sample processing, nisin is still present and can be quantified