A capillary electrophoresis system with dual capacitively coupled contactless conductivity detection and electrospray ionization tandem mass spectrometry

Abstract

A commercial system that is comprised of a CE coupled to an ESI triple quadrupole mass spectrometer was equipped with two capacitively coupled contactless conductivity detectors (C(4) Ds). The first C(4) D was positioned inside the original cartridge, and the second C(4) D was positioned as close as possible to the ESI probe entrance by using a 3D-printed support. The C(4) Ds electropherograms were matched to the ESI-MS electropherogram by correcting their timescales by the factor LT /LD , where LT and LD are the total capillary length and the length until the C(4) D, respectively. A general approach for method development supporting the simultaneous conductivity and MS detection is discussed, while application examples are introduced. These examples include the use of C(4) D as a simple device that dismiss the use of an EOF marker, a low-selectivity detector that continuously provide information about unexpected features of the sample, and even a detector that can be more sensitive than ESI-MS. The C(4) D used in this setup proved to have a smaller contribution to the peak broadening than ESI-MS, which allowed that a C(4) D, positioned at 12 cm from the inlet of an 80-cm-long capillary, could be used to foresee position and shape of the peaks being formed 6.8 times slower at the ESI-MS electropherogram.

Application of capillary electrophoresis combined with conductometric and UV detection to monitor meteorite simulant bioleaching by Acidithiobacillus ferrooxidans

“…Because the detectors are 10 cm apart from each other, species reach each detector at different time. Thus, just for comparison purpose, the migration times of all analytes in CE–UV were adjusted as described elsewhere (Fig. ).…”

Low‐cost and versatile analytical tool with purpose‐made capillary electrophoresis coupled to contactless conductivity detection: Application to antibiotics quality control in Vietnam

“…The appearance of their first oscillometric detector in 1998 [40] was followed by the second generation with hardware improvement in 2002 [42]. This group then moved toward the direction of open C 4 D [43,44] and 3Dbased CE-C 4 D design [45]. All these developments from both directions (i.e., purpose-made C 4 D and open C 4 D) aim at affordable analytical instrumentation for the population to the authors' viewpoint.…”

Contactless conductivity detection for analytical techniques: Developments from 2016 to 2018

“…Simultaneous detection of separated zones by two or even more unique detectors usually offers higher characterization power/improved analytical information. New detection systems combining C 4 D with mass spectrometry and C 4 D with mass spectrometry and amperometry were described recently. Data processing for CE‐C 4 D is usually carried out automatically on commercial CE instruments.…”

“…They found the two detectors to be complementary in that the C 4 D allowed the quantification of inorganic ions which were not accessible with the MS system while organic ions showed better sensitivity with the latter. Francisco and do Lago also combined C 4 D with mass‐spectrometric detection as an aid in optimizing the operating conditions. Müller et al.…”