Abstract
A two-infrared laser desorption/ionization method is described. A first laser, which was either an Er:YAG laser or an optical parametric oscillator (OPO), served for ablation/vaporization of small volumes of analyte/matrix sample at fluences below the ion detection threshold for direct matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). A second IR-laser, whose beam intersected the expanding ablation plume at a variable distance and time delay, was used to generate biomolecular ions out of the matrix-assisted laser desorption (MALD) plume. Either one of the two above lasers or an Er:YSGG laser was used for post-ionization. Glycerol was used as IR-MALDI matrix, and mass spectra of peptides, proteins, as well as nucleic acids, some of which in excess of 105 u in molecular weight, were recorded with a time-of-flight mass spectrometer. A mass spectrum of cytochrome c from a water ice matrix is also presented. The MALD plume expansion was investigated by varying the position of the post-ionization laser beam above the glycerol sample surface and its delay time relative to the desorption laser. Comparison between the OPO (pulse duration, τL=6 ns) and the Er:YAG laser (τL∼120 ns) as primary excitation laser demonstrates a significant effect of the laser pulse duration on the MALD process.
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References
Karas, M.; Bachmann, D.; Bahr, U.; Hillenkamp, F. Int. J. Mass Spectrom. Ion Processes 1987, 78, 53.
Karas, M.; Hillenkamp, F. Anal. Chem. 1988, 60, 2299.
Dreisewerd, K. Chem. Rev. 2003, 103, 395.
Dreisewerd, K.; Berkenkamp, S.; Leisner, A.; Rohlfing, A.; Menzel, C. Int. J. Mass Spectrom. 2003, 226, 189.
Zenobi, R.; Knochenmuss, R. Mass Spectrom. Rev. 1998, 17, 337.
Beavis, R. C.; Chait, B. T. Rapid Commun. Mass Spectrom. 1989, 3, 233.
Overberg, A.; Karas, M.; Bahr, U.; Kaufmann, R.; Hillenkamp, F. Rapid Commun. Mass Spectrom. 1990, 4, 293.
Overberg, A.; Karas, M.; Hillenkamp, F. Rapid Commun. Mass Spectrom. 1991, 5, 128.
Boesl, U.; Weinkauf, R.; Weickhardt, C.; Schlag, E. W. Int. J. Mass Spectrom. Ion Processes 1994, 131, 87, and references therein.
Schlag, E. W.; Grotemeyer, J.; Levine, R. D. Chem. Phys. Lett. 1992, 190, 521.
Morris, G. B.; Johnston, J. J. Phys. Chem. 1985, 89, 5399.
Rizzo, T. R.; Park, Y. D.; Petenau, L. A.; Levy, D. H. J. Chem. Phys. 1985, 83, 4990.
Von Helden, G.; Van Heijnsbergen, D.; Mejer, G. J. Phys. Chem. A 2003, 107, 1671.
Little, M. W.; Kim, J. K.; Murray, K. K. J. Mass Spectrom. 2003, 38, 772.
Noble, C. A.; Prather, K. A. Mass Spectrom. Rev. 2000, 19, 248.
Johnston, M. V. J. Mass Spectrom. 2000, 35, 585.
Murphy, D. M.; Thomson, D. S. Aerosol Sci. Res. 1995, 22, 237.
Hinz, K.-P.; Kaufmann, R.; Spengler, B. Anal. Chem. 1994, 66, 2071.
He, L.; Murray, K. K. J. Mass Spectrom. 1999, 34, 909.
Thomson, D. S.; Murphy, D. M. Appl. Opt. 1993, 32, 6818.
Dessiaterik, Y.; Nguyen, T.; Baer, T.; Miller, R. E. J. Phys. Chem. A 2003, 107, 11245.
Kleinekofort, W.; Avdiev, J.; Brutschy, B. Int. J. Mass Spectrom. Ion Processes 1996, 152, 135.
Wattenberg, A.; Sobott, F.; Brutschy, B. Rapid Commun. Mass Spectrom. 2000, 14, 859.
Wattenberg, A.; Sobott, F.; Barth, H. D.; Brutschy, B. Int. J. Mass Spectrom. 2000, 203, 49.
Hiraoka, K.; Saito, S.; Katsurawa, J.; Kudaka, I. Rapid Commun. Mass Spectrom. 1998, 12, 1170.
Menzel, C.; Dreisewerd, K.; Berkenkamp, S.; Hillenkamp, F. Int. J. Mass Spectrom. 2001, 207, 73.
Rohlfing, A.; Menzel, C.; Kukreja, L. M.; Hillenkamp, F.; Dreisewerd, K. J. Phys. Chem. B 2003, 107, 12275.
NIST Chemistry WebBook (http://webbook.nist.gov/chemistry).
Berkenkamp, S.; Menzel, C.; Karas, M.; Hillenkamp, F. Rapid Commun. Mass Spectrom. 1997, 11, 1399.
Kirpekar, F.; Berkenkamp, S.; Hillenkamp, F. Anal. Chem. 1999, 71, 2334.
Berkenkamp, S.; Karas, M.; Hillenkamp, F. Proc. Natl. Acad. Sci. U.S.A. 1996, 93, 7003.
Leisner, A. Dissertation, University of Münster, 2004.
Berkenkamp, S.; Menzel, C.; Hillenkamp, F.; Dreisewerd, K. J. Am. Soc. Mass Spectrom. 2002, 13, 209.
Menzel, C.; Dreisewerd, K.; Berkenkamp, S.; Hillenkamp, F. J. Am. Soc. Mass Spectrom. 2002, 13, 975.
Spengler, B.; Huber, M. J. Am. Soc. Mass Spectrom. 2002, 13, 735.
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Published online May 10, 2004
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Leisner, A., Rohlfing, A., Berkenkamp, S. et al. Infrared laser post-ionization of large biomolecules from an IR-MALD(I) plume. J Am Soc Mass Spectrom 15, 934–941 (2004). https://doi.org/10.1016/j.jasms.2004.03.010
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DOI: https://doi.org/10.1016/j.jasms.2004.03.010