title: Influence of matrix solution conditions on the MALDI-MS analysis of peptides and proteins.
abstract: Sample-matrix preparation procedures are shown to greatly influence the quality of the matrix-assisted laser desorption/ionization (MALDI) mass spectra of peptides and proteins. In particular, dramatic mass discrimination effects are observed when the matrix 4-hydroxy-alpha-cyanocinnamic acid is used for analyzing complex mixtures of peptides and proteins. The discrimination effects are found to be strongly dependent on the sample-matrix solution composition, pH, and the rates at which the sample-matrix cocrystals are grown. These findings demonstrate the need to exercise great care in performing and interpreting the MALDI analysis of biological samples. The results also indicate that there is a reverse-phase chromatographic-like dimension in the sample-matrix preparation procedures that can be exploited to optimize the analysis. The present work describes the conditions under which the majority of components of a complex mixture of peptides and proteins can be successfully measured.
authors.affiliation: Laboratory for Mass Spectrometry and Gaseous Ion Chemistry, Rockefeller University, New York, New York 10021, USA.
authors.forename: S L
authors.initials: SL
authors.lastname: Cohen
authors.forename: B T
authors.initials: BT
authors.lastname: Chait
mesh_terms: D000595:Amino Acid Sequence; D003460:Crystallization; D008969:Molecular Sequence Data; D010455:Peptides / Q000032:analysis* / Q000737:chemistry; D011506:Proteins / Q000032:analysis* / Q000737:chemistry; D012996:Solutions; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D010455:Peptides; D011506:Proteins; D012996:Solutions