An algorithm for baseline correction of MALDI mass spectra

ABSTRACT

Visualization and differentiation of proteins in tissue are problems of increasing interest in computational systems biology, bioinformatics, and image processing. A platform for generating such proteomic information is matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS). In imaging MALDI-MS, spatial information and protein expression can be created. However, data from imaging MALDI-MS spectra require considerable signal processing to generate quantitative results and to provide input to later classification algorithms. To compare MALDI-MS spectra at different spatial locations (sample-to-sample comparisons) or classify parts of the spectra, a processing step called baseline correction is essential. This paper reports a robust algorithm for computing the baseline correction of MALDI-MS spectra. The algorithm requires few user inputs and is suitable for automatically processing a large number of spectra, as is the case when generating images. The results of our algorithm are validated on a dataset of spectra available for comparison purposes.

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INDEX TERMS

Primary Classification:
  I. Computing Methodologies
  I.4 IMAGE PROCESSING AND COMPUTER VISION

Keywords:
MALDI, baseline correction, mass spectrometry, scientific visualization