Influence of the matrix on analyte fragmentation in atmospheric pressure MALDI

J Am Soc Mass Spectrom. 2006 Jul;17(7):1005-1013. doi: 10.1016/j.jasms.2006.03.009. Epub 2006 May 19.

Abstract

In this paper, we report the measurement of the degree of analyte fragmentation in AP-MALDI as a function of the matrix and of the laser fluence. The analytes include p-OCH3-benzylpyridinium, three peptides containing the sequence EEPP (which cleave very efficiently at the E-P site), and three deoxynucleosides (dA, dG, and dC), which lose the neutral sugar to give the protonated base. We found that the matrix hardness/softness was consistent when comparing the analytes, with a consensus ranking from hardest to softest: CHCA >> DHB > SA approximately THAP > ATT > HPA. However, the exact ranking can be fluence-dependent, for example between ATT and HPA. Our goal here was to provide the scientific community with a detailed dataset that can be used to compare with theoretical predictions. We tried to correlate the consensus ranking with different matrix properties: sublimation or decomposition temperature (determined using thermogravimetry), analyte initial velocity, and matrix proton affinity. The best correlation was found with the matrix proton affinity.

Publication types

  • Evaluation Study

MeSH terms

  • Atmospheric Pressure
  • Biocompatible Materials / chemistry*
  • Nucleosides / chemistry*
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / methods*

Substances

  • Biocompatible Materials
  • Nucleosides