title: Nanoliter segmented-flow sampling mass spectrometry with online compartmentalization.
abstract: We report a microfluidic device, using segmented flow in a two-phase system of immiscible liquids, which delivers aqueous droplets into a modified commercial mass spectrometer. The interface coupling the microfluidics to the mass spectrometer achieves up to 96% sample transfer efficiency to the vacuum chamber. Sample ionization is assisted by multipass infrared laser beam in the interface. The system achieves low femtomole detection limits of several analytes ranging from drugs to proteins. Sample ionization in this segmented-flow sampling was found to be remarkably insensitive to the presence of buffer salts and other matrices.
authors.affiliation: Department of Chemistry, University of Washington , Seattle, Washington 98195, United States.
authors.forename: Michael
authors.initials: M
authors.lastname: Volný
authors.forename: Joelle
authors.initials: J
authors.lastname: Rolfs
authors.forename: Bejan
authors.initials: B
authors.lastname: Hakimi
authors.forename: Petr
authors.initials: P
authors.lastname: Fryčák
authors.forename: Thomas
authors.initials: T
authors.lastname: Schneider
authors.forename: Dingsheng
authors.initials: D
authors.lastname: Liu
authors.forename: Gloria
authors.initials: G
authors.lastname: Yen
authors.forename: Daniel T
authors.initials: DT
authors.lastname: Chiu
authors.forename: František
authors.initials: F
authors.lastname: Tureček
mesh_terms: D006801:Humans; D061986:MCF-7 Cells; D013058:Mass Spectrometry; D036103:Nanotechnology