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Capillary array isoelectric focusing with laser-induced fluorescence detection: milli-pH unit resolution and yoctomole mass detection limits in a 32-channel system

Chemistry Department, University of Washington, Seattle, WA 98195-1700, USA.
Analytical and Bioanalytical Chemistry (Impact Factor: 3.58). 03/2010; 397(8):3305-10. DOI: 10.1007/s00216-010-3595-x
Source: PubMed

ABSTRACT We report a multiplexed capillary electrophoresis system employing an array of 32 capillaries with a micromachined sheath-flow cuvette as the detection chamber. The sample streams were simultaneously excited with a 473-nm laser beam, and the fluorescence emission was imaged on a CCD camera with a pair of doublet achromat lens. The instrument produced mass detection limits of 380 +/- 120 yoctomoles for fluorescein in zone electrophoresis. Capillary isoelectric focusing of fluorescent standards produced peaks with an average width of 0.0029 +/- 0.0008 pH. Capillary coating stability limits the reproducibility of the analysis.

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