title: Membrane-based emitter for coupling microfluidics with ultrasensitive nanoelectrospray ionization-mass spectrometry.
abstract: An integrated poly(dimethylsiloxane) (PDMS) membrane-based microfluidic emitter for high-performance nanoelectrospray ionization mass spectrometry has been fabricated and evaluated. The ∼100-μm-thick emitter was created by cutting a PDMS membrane that protrudes beyond the bulk substrate. The reduced surface area at the emitter enhances the electric field and reduces wetting of the surface by the electrospray solvent. As such, the emitter enables highly stable electrosprays at flow rates as low as 10 nL/min and is compatible with electrospray solvents containing a large organic component (e.g., 90% methanol). This approach enables facile emitter construction and provides excellent stability, reproducibility, and sensitivity as well as compatibility with multilayer soft lithography.
authors.affiliation: Biological Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, United States.
authors.forename: Xuefei
authors.initials: X
authors.lastname: Sun
authors.forename: Ryan T
authors.initials: RT
authors.lastname: Kelly
authors.forename: Keqi
authors.initials: K
authors.lastname: Tang
authors.forename: Richard D
authors.initials: RD
authors.lastname: Smith
mesh_terms: D004129:Dimethylpolysiloxanes / Q000737:chemistry; D008567:Membranes, Artificial; D044085:Microfluidics / Q000295:instrumentation*; D015203:Reproducibility of Results; D021241:Spectrometry, Mass, Electrospray Ionization / Q000295:instrumentation*
chemical_list: D004129:Dimethylpolysiloxanes; D008567:Membranes, Artificial; C013830:baysilon