Screen-printed digital microfluidics combined with surface acoustic wave nebulization for hydrogen-deuterium exchange measurements

J Chromatogr A. 2016 Mar 25:1439:161-166. doi: 10.1016/j.chroma.2015.12.048. Epub 2015 Dec 21.

Abstract

An inexpensive digital microfluidic (DMF) chip was fabricated by screen-printing electrodes on a sheet of polyimide. This device was manually integrated with surface acoustic wave nebulization (SAWN) MS to conduct hydrogen/deuterium exchange (HDX) of peptides. The HDX experiment was performed by DMF mixing of one aqueous droplet of angiotensin II with a second containing various concentrations of D2O. Subsequently, the degree of HDX was measured immediately by SAWN-MS. As expected for a small peptide, the isotopically resolved mass spectrum for angiotensin revealed that maximum deuterium exchange was achieved using 50% D2O. Additionally, using SAWN-MS alone, the global HDX kinetics of ubiquitin were found to be similar to published NMR data and back exchange rates for the uncooled apparatus using high inlet capillary temperatures was less than 6%.

Keywords: Hydrogen-deuterium exchange; Mass spectrometry; Screen-printed digital microfluidics; Surface acoustic wave nebulization.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Angiotensins / chemistry
  • Deuterium Exchange Measurement
  • Kinetics
  • Mass Spectrometry
  • Microfluidic Analytical Techniques
  • Peptides / chemistry*
  • Ubiquitin / chemistry

Substances

  • Angiotensins
  • Peptides
  • Ubiquitin