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DOE OSTI · 1031427

Accelerated High-Resolution Differential Ion Mobility Separations Using Hydrogen

Abstract

The resolving power of differential ion mobility spectrometry (FAIMS) was dramatically increased recently by the introduction of carrier gases comprising up to 75% He or various vapors, enabling many new applications. However, the gains were often at the expense of analysis speed, in particular making high-resolution FAIMS incompatible with online liquid-phase separations. Here, we report FAIMS employing hydrogen, specifically in mixtures with N2 containing up to 98.4% H2. Such compositions raise the mobilities of all ions and thus resolving power, while avoiding the electrical breakdown inevitable in He-rich mixtures. The increases of resolving power and ensuing peak resolution are especially significant at the greatest H2 fractions - above {approx}80 - 90%. Higher resolution can be exchanged for acceleration of the analyses by up to {approx}20 times. For more mobile species such as multiply-charged peptides, this exchange is presently forced by the constraints of existing FAIMS devices, but future designs optimized for H2 should consistently improve resolution for all analytes.

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BibTeXRIS

Shvartsburg, Alexandre A, Smith, Richard D. 2011-11-10. Accelerated High-Resolution Differential Ion Mobility Separations Using Hydrogen. https://doi.org/10.1021/ac202386w

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