title: A mechanical nanomembrane detector for time-of-flight mass spectrometry.
abstract: We describe here a new principle for ion detection in time-of-flight (TOF) mass spectrometry in which an impinging ion packet excites mechanical vibrations in a silicon nitride (Si(3)N(4)) nanomembrane. The nanomembrane oscillations are detected by means of time-varying field emission of electrons from the mechanically oscillating nanomembrane. Ion detection is demonstrated in the MALDI-TOF analysis of proteins varying in mass from 5729 (insulin) to 150,000 (Immunoglobulin G) daltons. The detector response agrees well with the predictions of a thermomechanical model in which the impinging ion packet causes a nonuniform temperature distribution in the nanomembrane, exciting both fundamental and higher order oscillations.
authors.affiliation: Electrical and Computer Engineering, University of Wisconsin, Madison, Wisconsin 53706, United States.
authors.forename: Jonghoo
authors.initials: J
authors.lastname: Park
authors.forename: Hua
authors.initials: H
authors.lastname: Qin
authors.forename: Mark
authors.initials: M
authors.lastname: Scalf
authors.forename: Ryan T
authors.initials: RT
authors.lastname: Hilger
authors.forename: Michael S
authors.initials: MS
authors.lastname: Westphall
authors.forename: Lloyd M
authors.initials: LM
authors.lastname: Smith
authors.forename: Robert H
authors.initials: RH
authors.lastname: Blick
mesh_terms: D000465:Algorithms; D000818:Animals; D001703:Biophysics / Q000379:methods; D015374:Biosensing Techniques / Q000379:methods*; D002417:Cattle; D006801:Humans; D007074:Immunoglobulin G / Q000737:chemistry; D007477:Ions; D015233:Models, Statistical; D053758:Nanoparticles / Q000737:chemistry; D036103:Nanotechnology / Q000379:methods*; D009991:Oscillometry / Q000379:methods; D012710:Serum Albumin, Bovine / Q000737:chemistry; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*
chemical_list: D007074:Immunoglobulin G; D007477:Ions; D012710:Serum Albumin, Bovine