Novel capacitively coupled contactless conductivity detector for capillary electrophoresis

ZIPFL, P.; KLER, PABLO A.; LUTZ, D.; MONIAK, A. ; HUHN, CAROLIN

Aalen

Conferencia; CE Forum; 2012

Capacitively coupled contactless conductivity detection (C4D) has been developed for detection in capillary electrophoresis (CE) and microfluidic applications by a number of groups [1,2]. However, only very few systems are commercially available. Beside the detection of non-UV-active compounds in CE separations, we wanted to apply a conductivity detector for capillary isotachophoresis in classical fused silica capillaries. With commercially available equipment (TraceDec®, eDAQ®), isotachophoretic steps were not sharp enough to allow precise quantification due to the relatively large detection volume comprised by the conductivity cell. We here present the characteristics of a novel C4D detector from CalvaSens which proved valuable for both capillary electrophoresis and capillary isotachophoresis. It provides a very low detection volume due to a reduced measuring distance along the capillary (integration length 1.5 mm) as well as a clearly improved range of resolvable conductivities. The excellent signal to noise ratio enables even shorter measuring distances as well as thinner capillary diameters. The detector can easily be incorporated into common cartridges of commercially available CE equipment. We here show its application to various CE and ITP analyses.