Method of mass spectrometric analysis from closely packed...

Chemistry: analytical and immunological testing – Nuclear magnetic resonance – electron spin resonance or other...

Reexamination Certificate

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C250S282000

Reexamination Certificate

active

07824920

ABSTRACT:
This application relates to a process for controllably placing two or more microspots on a target substrate in close proximity to one another. The microspots may then be simultaneously irradiated and the resulting ions detected by mass spectrometry, such as time of flight mass spectrometry. In one embodiment the size and spacing of the microspots on the substrate may be controlled by using an electrodynamic balance during the deposition step. The deposition procedure ensures that at least some of the microspots are spaced-apart on the substrate a distance less than the focused output of a single laser. Simultaneous irradiation of the adjacent microspots may cause desorption plumes of the microspots to interact in a gas phase, such as by ion-molecule reactions. The microspots may be configured to improve the ionization yield of the sample material in the gas phase and/or to increase the frequency of ion-molecule collisions in the gas phase. This allows for desorption of particular classes of compounds to be optimized independently of ionization. Different microspots could include different amounts or types of matrix compounds to enable simultaneously detection of compounds of varied physical and chemical properties within the same sample. One or more of the microspots may include calibrants or other additives for improving detecting accuracy or quantitation. Organized array of closely packed microspots may be created for use as standard reference materials or analyte detectors.

REFERENCES:
patent: 5041266 (1991-08-01), Fox
patent: 6287872 (2001-09-01), Schurenberg
patent: 7157234 (2007-01-01), Obremski et al.
patent: 2001/0008615 (2001-07-01), Little et al.
patent: 2002/0001853 (2002-01-01), Obremski et al.
patent: 2004/0063113 (2004-04-01), Agnes et al.
patent: 2008/0203289 (2008-08-01), Lemaire et al.
patent: 0235553 (2002-05-01), None
Little et al. “MALDI on a Chip: Analysis of Arrays of Low-Femtomole to Subfemtomole Quantities of Synthetic Oligonucleotides and DNA Diagnostic Products Dispensed by a Piezoelectric Pipet”, Anal. Chem. 1997, v. 69, pp. 4540-4546.
Sjödahl et al. “Chip with Twin Anchors for Reduced Ion Suppression and Improved Mass Accuracy in MALDI-TOF Mass Spectrometry”, Anal. Chem., 2005, v. 77, pp. 827-832.
Amiri-Eliasi, B., and Fenselau, C., “Characterization of protein biomarkers desorbed by MALDI from whole fungal cells”, Anal. Chem., 2001, 73:5228-5231.
Belov, Mikhail E., et al., “Chemical ionization of neutral peptides produced by matrix-assisted laser desorption”, Chemical Physics Letters, 1998, 284:412-418.
Berkenkamp, Stefan, et al., “Infrared MALDI mass spectrometry of large nucleic acids”, Science, 1998, 281:260-262.
Bogan, Michael J., and Agnes, George R., “MALDI-TOF-MS analysis of droplets prepared in an electrodynamic balance: wall-less sample preparation”, Anal. Chem., 2002, 74:489-496.
Bogan, Michael J. and Agnes, George R., “Poly(ethylene glycol) doubly and singly cationized by different alkali metal ions: relative cation affinities and cation-dependent resolution in a quadrupole ion trap mass spectrometer”, J. Am. Soc. Mass Spectrom., 2002, 13:177-186.
Bogan, Michael J. and Agnes, George R., “Time-of-flight mass spectrometric analysis of ions produced from adjacent sample spots irradiated simultaneously by a single 337 nm laser”, Rapid Commun. Mass Spectrom., 2003, 17:2557-2562.
Brivio, Monica, et al., “Integrated microfluidic system enabling (Bio)chemical reactions with on-line MALDI-TOF mass spectrometry”, Anal. Chem., 2002, 74:3972-3976.
Caprioli, Richard M., et al., “Molecular imaging of biological samples: localization of peptides and proteins using MALDI-TOF MS”, Analytical Chemistry, 1997, 69(23):4751-4760.
Chaurand, Pierre, et al., “Direction profiling of proteins in biological tissue sections by MALDI mass spectrometry”, Anal. Chem., 1999, 71:5263-5270.
Davis, E. James, et al., “The double-ring electrodynamic balance for microparticle characterization”, Rev. Sci. Instrum., 1990, 61(4):1281-1288.
Dreiswerd, Klaus, “The desorption process in MALDI”, Chem., Rev., 2003, 103:395-425.
Ekstrom, Simon, et al., “Integrated microanalytical technology enabling rapid and automated protein identification”, Anal. Chem., 2000, 72:286-293.
Ekstrom, Simon, et al., “Signal amplification using “spot-on-a-chip” technology for the identification of proteins via MALDI-TOF MS”, Anal. Chem., 2001, 73:214-219.
Feng, X. and Agnes, George R., “Single isolated droplets with net charge as a source of ions”, J. Am. Soc. Mass Spectrom, 2000, 11:393-399.
Feng, Xiao, et al., “Coulomb fission event resolved progeny droplet production from isolated evaporating methanol droplets”, Anal. Chem., 2001, 73:4499-4507.
Garden, Rebecca W. and Sweedler, Jonathan V., “Heterogeneity within MALDI samples as revealed by mass spectrometric imaging”, Anal. Chem., 2000, 72:30-36.
Gidden, Jennifer, et al., “Gas-phase conformations of synthetic polymers: poly(ethylene glycol), poly(propylene glycol), and poly(tetramethylene glycol)”, J. Am. Chem. Soc., 2000, 122:4692-4699.
Gluckman, Matthias, et al., “Mechanisms in MALDI analysis: surface interaction or incorporation of analytes?”, Int. J. Mass Spectrom., 2001, 210/211:121-132.
Gobom, Johan, et al., “Alpha-cyano-4-hydroxycinnamic acid affinity sample preparation. A protocol for MALDI-MS peptide analysis in proteomics”, Anal. Chem., 2001, 73:434-438.
Guan, Shenheng and Marshall, Alan G., “Equilibrium space charge distribution in a quadrupole ion trap”, J. Am. Soc. Mass Spectrom., 1994, 5:64-71.
Hillenkamp, Franz, et al., “Matrix-assisted laser desorption/ionization mass spectrometry of biopolymers”, Anal. Chem., 1991, 63(24):1193A-1203A.
Johnson, J.V. and Yost, R.A., “Tandem mass spectrometry for trace analysis”, Anal. Chem., 1985, 57:758A-768A.
Karas, M., et al., “Principles and applications of matrix-assisted UV-laser desorption/ionization mass spectrometry”, Analytica Chimica Acta, 1990, 241:175-185.
Karas, Michael, et al., “Matrix-assisted laser desorption ionization mass spectrometry”, Mass Spectrometry Reviews, 1991, 10(5):335-357.
Karas, M. and Hillenkamp, F., “Laser desorption ionization of proteins with molecular masses exceeding 10 000 daltons”, Anal. Chem., 1988, 60:2299-2301.
Keller, Bernd O. and Li, Liang, “Detection of 25,000 molecules of substance P by MALDI-TOF mass spectrometry and investigations into the fundamental limits of detection in MALDI”, J. Am. Soc. Mass Spectrom., 2001, 12:1055-1063.
Kinsel, Gary R., et al., “Investigation of the dynamics of matrix-assisted laser desorption/ionization formation using an electrostatic analyzer/time-of-flight mass spectrometer”, J. Mass Spectrom., 1999, 34:684-690.
Knochenmuss, Richard and Vertes, Akos, “Time-delayed 2-pulse studies of MALDI matrix ionization mechanisms”, J. Phys. Chem. B, 2000, 104:5406-5410.
Knochenmuss, R., et al., “Secondary ion-molecule reactions in matrix-assisted laser desorption/ionization”, J. Mass Spectrom., 2000, 35:1237-1245.
Knochenmuss, Richard, “A quantitative model of ultraviolet matrix-assisted laser desorption/ionization including analyte ion generation”, Anal. Chem., 2003, 75:2199-2207.
Kruse, Rebecca and Sweedler, Jonathan V., “Spatial profiling invertebrate ganglia using MALDI MS”, J. Am. Soc. Mass Spectrom, 2003, 14:752-759.
Leary, James J. and Schmidt, Rebecca L., “Quadrupole mass spectrometers: an intuitive look at the math”, Journal of Chemical Education, 1996, 73(12):1142-1144.
Ledford, Edward E., et al., “Space charge effects in fourier transform mass spectrometry. Mass calibration”, Anal. Chem., 1984, 56:2744-2748.
Li, Liang, et al.,

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