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Efficient electrospray ionization from polymer microchannels using integrated hydrophobic membranes.

Ying-Xin Wang·Jon W Cooper·Cheng S Lee·Don L DeVoe
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Abstract

A simple process for realizing stable and reliable electrospray ionization (ESI) tips in polymer microfluidic systems is described. The process is based on the addition of a thin hydrophobic membrane at the microchannel exit to constrain lateral dispersion of the Taylor cone formed during ESI. Using this approach, ESI chips are shown to exhibit well-defined Taylor cones at flow rates as low as 80 nL min(-1) through optical imaging. Furthermore, stable electrospray current has been measured for flow rates as low as 10 nL min(-1) over several hours of continuous operation. Characterization of the electrospray process by optical and electrical monitoring of fabricated ESI chips is reported, together with mass spectrometry validation using myoglobin as a model protein. The novel process offers the potential for low-cost, direct interfacing of disposable polymer microfluidic separation platforms to mass spectrometry.

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Membrane ProteinsMicrofluidicsMyoglobinPolymersSpectrometry, Mass, Electrospray IonizationJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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Ying-Xin Wang, Jon W Cooper, Cheng S Lee, Don L DeVoe. 2004-04-28. Efficient electrospray ionization from polymer microchannels using integrated hydrophobic membranes.. https://doi.org/10.1039/b402825b

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