Abstract
Large signals from α-cyano-4-hydroxycinnamic acid (CHCA) matrix complexes with sodium and potassium ions were found to interfere with sensitive matrix-assisted laser desorption/ionization (MALDI) analysis of a hydrochloric acid digest of gelatine preparations. The nature of some selected matrix clusters was investigated by conventional post-source decay and LIFT-TOF/TOF experiments. The matrix clusters fragmented readily by neutral evaporation to give smaller sized matrix cluster species without matrix disintegration. Their characterization distinguished them from peptide signals, in particular from those that had the same nominal mass and differed only in the fractional part of the mass as encountered for gelatine-derived peptides. Knowledge of the molecular composition of these cluster species allowed using them for internal calibration of the MALDI mass spectra. The hydrolytic peptides could be analyzed with increased sensitivity when using 2,5-dihydroxy benzoic acid (DHB) as the MALDI matrix.
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References
Aebersold, R.; Goodlett, D. R. Mass Spectrometry in Proteomics. Chem. Rev. 2001, 101, 269–295.
Keller, B. O.; Li, L. 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.
Dreisewerd, K. The Desorption Process in MALDI. Chem. Rev. 2003, 103, 395–425.
Krutchinsky, A. N.; Chait, B. T. On the Nature of the Chemical Noise in MALDI Mass Spectra. J. Am. Soc. Mass Spectrom. 2002, 13, 129–134.
Beavis, R. C.; Chait, B. T. High-Accuracy Molecular Mass Determination of Proteins Using Matrix-Assisted Laser Desorption Mass Spectrometry. Anal. Chem. 1990, 62, 1836–1840.
O’Connor, P. B.; Mirgorodskaya, E.; Costello, C. E. High Pressure Matrix-Assisted Laser Desorption/Ionization Fourier Transform Mass Spectrometry for Minimization of Ganglioside Fragmentation. J. Am. Soc. Mass Spectrom. 2002, 13, 402–407.
Karas, M.; Glückmann, M.; Schäfer, J. Ionization in Matrix-Assisted Laser Desorption/Ionization: Singly Charged Molecular Ions are the Lucky Survivors. J. Mass Spectrom. 2000, 35, 1–12.
Karas, M.; Krüger, R. Ion Formation in MALDI: The Cluster Ionization Mechanism. Chem. Rev. 2003, 103, 427–439.
Keller, B. O.; Li, L. Discerning Matrix-Cluster Peaks in Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectra of Dilute Peptide Mixtures. J. Am. Soc. Mass Spectrom. 2000, 11, 88–93.
Harris, W. A.; Janecki, D. J.; Reilly, J. P. Use of Matrix Clusters and Trypsin Autolysis Fragments as Mass Calibrants in Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry. Rapid Commun. Mass Spectrom. 2002, 16, 1714–1722.
Karty, J. A.; Ireland, M. M. E.; Brun, Y. V.; Reilly, J. P. Artifacts and Unassigned Masses Encountered in Peptide Mass Mapping. J. Chromatogr. B. 2002, 782, 363–383.
Fernandez Ocaña, M.; Neubert, H.; Parker, R.; Bramley, P.; Halket, J.; Patel, R. BSE Control: Detection of Gelatine-Derived Peptides in Animal Feed by Mass Spectrometry. Analyst, in press
Gobom, J.; Müller, M.; Egelhofer, V.; Theiss, D.; Lehrach, H.; Nordhoff, E. A Calibration Method that Simplifies and Improves Accurate Determination of Peptide Molecular Masses by MALDI-TOF MS. Anal. Chem. 2002, 74, 3915–3923.
La Rotta, A.; Holle, A. E.; Hillenkamp, F. LIFT: High Sensitivity Single Scan MALDI-TOF MS/MS. Proceedings of the 49th ASMS Annual Conference on Mass Spectrometry and Allied Topics; Chicago, IL, May, 2001
Suckau, D.; Resemann, A.; Schürenberg, M.; Hufnagel, P.; Franzen, J.; Holle, A. A Novel MALDI LIFT-TOF/TOF Mass Spectrometer for Proteomics. Anal. Bioanal. Chem. 2003, 376, 952–965.
Schürenberg, M.; Lübbert, C.; Eickhoff, H.; Kalkum, M.; Lehrach, H.; Nordhoff, E. Prestructured MALDI-MS Sample Supports. Anal. Chem. 2000, 72, 3436–3442.
Gobom, J.; Schürenberg, M.; Müller, M.; Theiss, D.; Lehrach, H.; Nordhoff, E. α-Cyano-4-Hydroxycinnamic Acid Affinity Aample Preparation. A Protocol for MALDI-MS Peptide Analysis in Proteomics. Anal. Chem. 2001, 73, 434–438.
Karas, M.; Bahr, U.; Strupat, K.; Hillenkamp, F.; Tsarbopoulos, A.; Pramanik, B. N. Matrix Dependence of Metastable Fragmentation of Glycoproteins in MALDI TOF Mass Spectrometry. Anal. Chem. 1995, 67, 675–679.
Gay, S.; Binz, P. A.; Hochstrasser, D. F.; Appel, R. D. Modeling Peptide Mass Fingerprinting Data Using the Atomic Composition of Peptides. Electrophoresis. 1999, 20, 3527–3534.
Lee, S. W.; Kim, H. S.; Beauchamp, J. L. Salt Bridge Chemistry Applied to Gas-Phase Peptide Sequencing: Selective Fragmentation of Sodiated Gas-Phase Peptide Ions Adjacent to Aspartic Acid Residues. J. Am. Chem. Soc. 1998, 120, 3188–3195.
Lin, T.; Payne, A. H.; Glish, G. L. Dissociation Pathways of Alkali-Cationized Peptides: Opportunities for C-terminal Peptide Sequencing. J. Am. Soc. Mass Spectrom. 2001, 12, 497–504.
Cerda, B. A.; Cornett, L.; Wesdemiotis, C. Probing the Interaction of Alkali and Transition Metal Ions with Bradykinin and its des-Arginine Derivatives via Matrix-Assisted Laser Desorption/Ionization and Postsource Decay Mass Spectrometry. Int. J. Mass Spectrom. 1999, 193, 205–226.
Dreisewerd, K.; Schürenberg, M.; Karas, M.; Hillenkamp, F. Influence of the Laser Intensity and Spot Size on the Desorption of Molecules and Ions in Matrix-Assisted Laser-Desorption Ionization with a Uniform Beam Profile. Int. J. Mass Spectrom. Ion Processes. 1995, 141, 127–148.
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Published online January 15, 2004
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Neubert, H., Halket, J.M., Fernandez Ocaña, M. et al. MALDI post-source decay and LIFT-TOF/TOF investigation of α-cyano-4-hydroxycinnamic acid cluster interferences. J Am Soc Mass Spectrom 15, 336–343 (2004). https://doi.org/10.1016/j.jasms.2003.11.002
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DOI: https://doi.org/10.1016/j.jasms.2003.11.002