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Title: Microfabricated quadrupole ion trap for mass spectrometer applications

Authors:
 [1];  [2];  [2];  [3];  [4];  [4];  [5]
  1. University of Arizona/Bell Labs
  2. Lucent Technologies/Bell Laboratories
  3. {nmn} [ORNL
  4. ORNL
  5. University of North Carolina
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
Work for Others (WFO)
OSTI Identifier:
1003290
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 96; Journal Issue: 12
Country of Publication:
United States
Language:
English

Citation Formats

Pau, Dr. Stanley, Pai, C. S., Low, Y., Moxom, Jeremy, Reilly, Pete, Whitten, William B, and Ramsey, Dr. John Michael. Microfabricated quadrupole ion trap for mass spectrometer applications. United States: N. p., 2006. Web. doi:10.1103/PhysRevLett.96.120801.
Pau, Dr. Stanley, Pai, C. S., Low, Y., Moxom, Jeremy, Reilly, Pete, Whitten, William B, & Ramsey, Dr. John Michael. Microfabricated quadrupole ion trap for mass spectrometer applications. United States. doi:10.1103/PhysRevLett.96.120801.
Pau, Dr. Stanley, Pai, C. S., Low, Y., Moxom, Jeremy, Reilly, Pete, Whitten, William B, and Ramsey, Dr. John Michael. Sun . "Microfabricated quadrupole ion trap for mass spectrometer applications". United States. doi:10.1103/PhysRevLett.96.120801.
@article{osti_1003290,
title = {Microfabricated quadrupole ion trap for mass spectrometer applications},
author = {Pau, Dr. Stanley and Pai, C. S. and Low, Y. and Moxom, Jeremy and Reilly, Pete and Whitten, William B and Ramsey, Dr. John Michael},
abstractNote = {},
doi = {10.1103/PhysRevLett.96.120801},
journal = {Physical Review Letters},
number = 12,
volume = 96,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
  • An array of miniaturized cylindrical quadrupole ion traps, with a radius of 20 {mu}m, is fabricated using silicon micromachining using phosphorus doped polysilicon and silicon dioxide for the purpose of creating a mass spectrometer on a chip. We have operated the array for mass-selective ion ejection and mass analysis using Xe ions at a pressure of 10{sup -4} Torr. The scaling rules for the ion trap in relation to operating pressure, voltage, and frequency are examined.
  • We present a laboratory-constructed mass spectrometer optimized for recording infrared multiple photon dissociation (IRMPD) spectra of mass-selected ions using a benchtop tunable infrared optical parametric oscillator/amplifier (OPO/A). The instrument is equipped with two ionization sources, an electrospray ionization source, as well as an electron ionization source for troubleshooting. This hybrid mass spectrometer is composed of a quadrupole mass filter for mass selection, a reduced pressure ({approx}10{sup -5} Torr) quadrupole ion trap (QIT) for OPO irradiation, and a reflectron time-of-flight drift tube for detecting the remaining precursor and photofragment ions. A helium gas pulse is introduced into the QIT to temporarilymore » increase the pressure and hence enhance the trapping efficiency of axially injected ions. After a brief pump-down delay, the compact ion cloud is subjected to the focused output from the continuous wave OPO. In a recent study, we implemented this setup in the study of protonated tryptophan, TrpH{sup +}, as well as collision-induced dissociation products of this protonated amino acid [W. K. Mino, Jr., K. Gulyuz, D. Wang, C. N. Stedwell, and N. C. Polfer, J. Phys. Chem. Lett. 2, 299 (2011)]. Here, we give a more detailed account on the figures of merit of such IRMPD experiments. The appreciable photodissociation yields in these measurements demonstrate that IRMPD spectroscopy of covalently bound ions can be routinely carried out using benchtop OPO setups.« less
  • Positive-mode atmospheric pressure chemical ionization tandem mass spectrometry (APCI-MS n ) was tested for the differentiation of regioisomeric aromatic ketocarboxylic acids. Each analyte forms exclusively an abundant protonated molecule upon ionization via positive-mode APCI in a commercial linear quadrupole ion trap (LQIT) mass spectrometer. Energy-resolved collision-activated dissociation (CAD) experiments carried out on the protonated analytes revealed fragmentation patterns that varied based on the location of the functional groups. Unambiguous differentiation between the regioisomers was achieved in each case by observing different fragmentation patterns, different relative abundances of ion-molecule reaction products, or different relative abundances of fragment ions formed at differentmore » collision energies. The mechanisms of some of the reactions were examined by H/D exchange reactions and molecular orbital calculations.« less