A microfluidic reactor for rapid, low-pressure proteolysis with on-chip electrospray ionization
Article first published online: 4 JAN 2010
Copyright © 2010 John Wiley & Sons, Ltd.
Rapid Communications in Mass Spectrometry
Volume 24, Issue 3, pages 315–320, 15 February 2010
How to Cite
Liuni, P., Rob, T. and Wilson, D. J. (2010), A microfluidic reactor for rapid, low-pressure proteolysis with on-chip electrospray ionization. Rapid Commun. Mass Spectrom., 24: 315–320. doi: 10.1002/rcm.4391
- Issue published online: 4 JAN 2010
- Article first published online: 4 JAN 2010
- Manuscript Accepted: 18 NOV 2009
- Manuscript Revised: 29 OCT 2009
- Manuscript Received: 7 SEP 2009
A microfluidic reactor that enables rapid digestion of proteins prior to on-line analysis by electrospray ionization mass spectrometry (ESI-MS) is introduced. The device incorporates a wide (1.5 cm), shallow (10 µm) reactor ‘well’ that is functionalized with pepsin-agarose, a design that facilitates low-pressure operation and high clogging resistance. Electrospray ionization is carried out directly from a short metal capillary integrated into the chip outlet. Fabrication, involving laser ablation of polymethyl methacrylate (PMMA), is exceedingly straightforward and inexpensive. High sequence coverage spectra of myoglobin (Mb), ubiquitin (Ub) and bovine serum albumin (BSA) digests were obtained after <4 s of residence time in the reactor. Stress testing showed little loss of performance over ∼2 h continuous use at high flow rates (30 µL/min). The device provides a convenient platform for a range of applications in proteomics and structural biology, i.e. to enable high-throughput workflows or to limit back-exchange in spatially resolved hydrogen/deuterium exchange (HDX) experiments. Copyright © 2010 John Wiley & Sons, Ltd.