Radiant energy – Ionic separation or analysis – With sample supply means
Reexamination Certificate
2000-06-14
2003-10-07
Berman, Jack (Department: 2881)
Radiant energy
Ionic separation or analysis
With sample supply means
C250S42300F, C250S382000
Reexamination Certificate
active
06630664
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a monitor that can detect trace molecules from a sample. By way of example, the monitor may be a mass spectrometer.
2. Background Information
Mass spectrometers are typically used to detect one or more trace molecules from a sample. For example, a mass spectrometer can be used to detect the existence of toxic or otherwise dangerous compounds in a room. Mass spectrometers are also used to analyze drug compounds in solvents. Mass spectrometers typically ionize trace molecules from a gas sample and then deflect the ionized molecules into a detector. The detector may detect the mass of the ionized molecule by measuring the time required for the molecule to travel across a chamber or by other means. The identity of the molecule can then be determined from the mass.
U.S. Pat. No. 5,808,299 issued to Syage discloses a mass spectrometer that contains a photoionizer. The photoionizer includes a light source that can emit a light beam into a gas sample. The light beam has an energy that will ionize constituent molecules without creating an undesirable amount of fragmentation. The molecules are ionized at low pressures. Low pressure ionization is not as effective in detecting small concentrations of molecules.
U.S. Pat. No. 4,849,628 issued to McLuckey et al. (“McLuckey”) discloses a mass detection system that can detect relatively low concentrations of a trace molecule. McLuckey utilizes a glow discharge ionizer that ionizes an “atmospheric” sample. Providing an air sample at atmospheric pressures increases the density of the sample and the number of ionized molecules. Increasing the number of ions improves the sensitivity of the detector. Although McLuckey uses the term atmospheric, ionization actually occurs in an ionization chamber having a pressure between 0.1 to 1.0 torr.
It is generally desirable to provide a mass spectrometer that can detect a number of different compounds; provides a strong molecular ion signal with minimal fragmentation; is not susceptible to interference and gives a linear response with concentration.
It would be desirable to provide a photoionizer that can handle large quantities of sample in order to use with various liquid flow sources such as liquid chromatography and separation columns. It would also be desirable to provide a photoionizer that ionizes analyte in liquid samples by a means other than thermal vaporization.
BRIEF SUMMARY OF THE INVENTION
One embodiment of the present invention is a monitor that can detect a trace molecule in a sample provided by an inlet at approximately one atmosphere. The trace molecule can be ionized by a photoionizer coupled to the inlet. The trace molecule can be detected by a detector.
REFERENCES:
patent: 3555272 (1971-01-01), Munson et al.
patent: 4239967 (1980-12-01), Carr et al.
patent: 4365157 (1982-12-01), Unsöld et al.
patent: 4433241 (1984-02-01), Boesl et al.
patent: 4531056 (1985-07-01), Labowsky et al.
patent: 4540884 (1985-09-01), Stafford et al.
patent: 4733073 (1988-03-01), Becker et al.
patent: 4780608 (1988-10-01), Cross et al.
patent: 4804846 (1989-02-01), Hall
patent: 4849628 (1989-07-01), McKuckey et al.
patent: 4855594 (1989-08-01), Kimock et al.
patent: 4861988 (1989-08-01), Henion et al.
patent: 4931640 (1990-06-01), Marshall et al.
patent: 4982097 (1991-01-01), Slivon et al.
patent: 5032721 (1991-07-01), Bacon et al.
patent: 5070240 (1991-12-01), Lee et al.
patent: 5153672 (1992-10-01), Globig et al.
patent: 5206594 (1993-04-01), Zipf
patent: 5234838 (1993-08-01), Bacon, Jr.
patent: 5283436 (1994-02-01), Wang
patent: 5294797 (1994-03-01), Frey et al.
patent: 5311016 (1994-05-01), Villa-Aleman
patent: 5338931 (1994-08-01), Spangler et al.
patent: 5343488 (1994-08-01), Guyot et al.
patent: 5381006 (1995-01-01), Wells et al.
patent: 5393979 (1995-02-01), Hsi
patent: 5397895 (1995-03-01), Leone et al.
patent: 5412207 (1995-05-01), Micco et al.
patent: 5469323 (1995-11-01), Kanayama
patent: 5504328 (1996-04-01), Bonser
patent: 5527731 (1996-06-01), Yamamoto et al.
patent: 5554846 (1996-09-01), Regiec et al.
patent: 5569917 (1996-10-01), Buttrill, Jr. et al.
patent: 5631462 (1997-05-01), Reentz, Jr.
patent: 5808299 (1998-09-01), Syage
patent: 5826214 (1998-10-01), Lieb et al.
patent: 5854431 (1998-12-01), Linker et al.
patent: 5869832 (1999-02-01), Wang et al.
patent: 5906946 (1999-05-01), Sausa et al.
patent: 6011259 (2000-01-01), Whitehouse et al.
patent: 6040575 (2000-03-01), Whitehouse et al.
patent: 6140638 (2000-10-01), Tanner et al.
patent: WO 01/33605 (2001-05-01), None
Revel'skii et al., Mass Spectrometry With Photoionization at Atmospheric Pressure and the Analysis of Multicomponent Mixtures Without Separation, Chemical and Physicochemical Methods of Analysis, 1991, Plenum Publishing Corporation, pp. 243-248.*
“Tunable VUV Radiation Generated by Two-Photon Resonant Frequency Mixing in Zenon,” IEEE Journal of Quantum Electronics, vol. QE-19, No. 2, Feb. 1983.
“Real-Time Detection of Chemical Agents Using Molecular Beam Laser Mass Spectrometry,” Jack A. Syage, Aerophysics Laboratory, Reprinted from Analytical Chemistry, 1990, 62.
“New Developments in Molecular Detection by Supersonic Moecular Beam, Laser Mass Spectrometry,” Jack A. Syage, pp. 469-489.
“Cyclic Ketone Mixture Analysis Using 2 + 1 Resonance-Enhanced Multiphoton Ionization Mass Spectrometry, ” Dale R. Nesselrodt et al., Anal. Chem. 1994, 66, 2497-2504.
“Pulsed Laser Desorption of Biological Molecules in Supersonic Beam Mass Spectrometry W/Resonant Two-Photon Ionization Detection,” R. Tembreull, Anal. Chem. 1987, 59, 1082-1088.
“A Hybrid Instrument that Combines TOF With the Ion Trap Yields Excellent Sensitivity for Small Samples,” Anal. Chem. vol. 67, No. 7, Apr. 1, 1995.
“An Ion Trap Storage/Time-of-Flight Mass Spectrometer,” S.M. Michael et al., Rev. Sci. Instrum. 63 (10), Oct. 1992, pp. 4277-4284.
“Third-Harmonic Generation in Argon, Krypton, & Xenon: Bandwidth Limitations in the Vicinity of Lyman-a,” R. Mahon IEEE Journal of Quantum Electronics, vol. QE-15, No. 6, 6/79.
Pulsed Free Jets: Novel Nonlinear Media for Generation of Vacuum Ultraviolet and Extreme Ultraviolet Radiation,: J. Phys. Chem. 1984, 88,4459-4465.
“Compact Vacuum Ultraviolet Source for Photoelectron Spectroscopy,” Rev. Sci. Instrum. 60(7), Jul. 1989.
“Generation of Narrowband Tunable VUV Radiation at the Lyman-a Wavelength,” Optics Communications, vol. 33, No. 1, Apr. 1980.
R. Frey, et al. “Real-Time Vehicle Exhaust Analysis Using a Laser TOF Mass Spectrometer” Proc. 40thAnal. Conf. Mass Spectrom & Allied Topics, 1992, pp 678-679.
E.R. Rohwer, R.C. Beavis,C. Koster, J. Lindner, J. Grotemeyer and E.W. Schlag, “Fast Pulsed Laser Induced Electron Generation for Electron Impact Mass Spectrometry”, Nov. 23, 1988, pp. 1151-1153.
J.G. Boyle, L.D. Pfefferle, E.E. Gulcicek, S.D. Colson, “Laser-driven Electron Ionization for a VUV Photoionization Time-Of-Flight Mass Spectrometer”, (11) pp.; American Institute of Physics.
P.Y. Cheng and H.L. Dai, “A Photoemitted Electron-Impact Ionization Method For Time-Of-Flight Mass Spectrometers”, pp. 2211-2214, American Institute of Physics.
U. Boesl et al. “Laser Ion Sources For Time-Of-Flight Mass Spectrometry”, Int. J. Mass Spectrom. Ion Processes 131 (1994) 87-124.
Evans Matthew D.
Hanold Karl A.
Liu Yong
Syage Jack A.
Berman Jack
Irell & Manella LLP
Syagen Technology
LandOfFree
Atmospheric pressure photoionizer for mass spectrometry does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Atmospheric pressure photoionizer for mass spectrometry, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Atmospheric pressure photoionizer for mass spectrometry will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3130827