TY - JOUR T1 - Disappearance of interfering alkali-metal adducted peaks from matrix-assisted laser desorption/ionization mass spectra of peptides with serine addition to alpha-cyano-4-hydroxycinnamic acid matrix. AU - Nishikaze,Takashi, AU - Takayama,Mitsuo, PY - 2007/9/21/pubmed PY - 2007/11/9/medline PY - 2007/9/21/entrez SP - 3345 EP - 51 JF - Rapid communications in mass spectrometry : RCM JO - Rapid Commun Mass Spectrom VL - 21 IS - 20 N2 - It has been described that ion yield in both positive- and negative-ion matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS) of peptides is often inhibited by trace amounts of alkali metals and that the MALDI mass spectra are contaminated by the interfering peaks originating from traces of alkali metals, even when sample preparation is carefully performed. Addition of serine to the commonly used MALDI matrix alpha-cyano-4-hydroxycinnamic acid (CHCA) significantly improved and enhanced the signals of both protonated and deprotonated peptides, [M+H](+) and [M-H](-). The addition of serine to CHCA matrix eliminated the alkali-metal ion adducts, [M+Na](+) and [M+K](+), and the CHCA cluster ions from the mass spectra. Serine and serinephosphate as additives to CHCA enhanced and improved the formation of molecular-related ions of phosphopeptides in negative-ion MALDI mass spectra. SN - 0951-4198 UR - https://www.unboundmedicine.com/medline/citation/17880041/Disappearance_of_interfering_alkali_metal_adducted_peaks_from_matrix_assisted_laser_desorption/ionization_mass_spectra_of_peptides_with_serine_addition_to_alpha_cyano_4_hydroxycinnamic_acid_matrix_ DB - PRIME DP - Unbound Medicine ER -