Abstract
Microchip capillary electrophoresis with laser-induced fluorescence detection (μCE-LIF) enables sensitive analyses of a wide range of analytes employing small volumes of sample and reagent (nL to μL) on an instrument platform with minimal mass, volume, and power requirements. This technique has been used previously in the analysis of amino acids and other organic molecules of interest in the fields of astrobiology and planetary science. Here, we present a protocol for the analysis of thiols using μCE-LIF. This protocol utilizes Pacific Blue C5-maleimide for fluorescent derivatization of thiols, enabling limits of detection in the low nM range (1.4–15 nM). Separations are conducted in micellar electrokinetic chromatography mode with 25 mM sodium dodecyl sulfate in 15 mM tetraborate, pH 9.2. This method allows analysis of 12 thiols in less than 2 min following a labeling step of 2 h. A step-by-step protocol, including tips on microchip capillary electrophoresis, is described here.
Copyright 2012 California Institute of Technology. Government sponsorship acknowledged.
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Acknowledgments
The research described here was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. Financial support for this project was provided by ASTID (Project #104320) and the NASA Postdoctoral Program (NPP) at the Jet Propulsion Laboratory, administered by Oak Ridge Associated Universities through a contract with NASA.
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Mora, M.F., Stockton, A.M., Willis, P.A. (2015). Analysis of Thiols by Microchip Capillary Electrophoresis for In Situ Planetary Investigations. In: Van Schepdael, A. (eds) Microchip Capillary Electrophoresis Protocols. Methods in Molecular Biology, vol 1274. Humana Press, New York, NY. https://doi.org/10.1007/978-1-4939-2353-3_4
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DOI: https://doi.org/10.1007/978-1-4939-2353-3_4
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