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Analysis of native amino acid and peptide enantiomers by high‐performance liquid chromatography/atmospheric pressure chemical ionization mass spectrometry
Author(s) -
Desai Meera J.,
Armstrong Daniel W.
Publication year - 2004
Publication title -
journal of mass spectrometry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.475
H-Index - 121
eISSN - 1096-9888
pISSN - 1076-5174
DOI - 10.1002/jms.571
Subject(s) - chemistry , atmospheric pressure chemical ionization , chromatography , formic acid , electrospray ionization , mass spectrometry , enantiomer , high performance liquid chromatography , chemical ionization , amino acid , peptide , ionization , protein mass spectrometry , analytical chemistry (journal) , ion , organic chemistry , biochemistry
High‐performance liquid chromatography (HPLC) coupled to atmospheric pressure chemical ionization (APCI) mass spectrometry was used for the separation and detection of amino acid and peptide enantiomers. With detection limits as low as 250 pg, 25 amino acids enantiomers were baseline resolved on a Chirobiotic T chiral stationary phase. APCI demonstrated an order of magnitude better sensitivity over electrospray ionization (ESI) for free amino acids and low molecular mass peptides at the high LC flow‐rates necessary for rapid analysis. As the peptide chain length increased (peptides with M r ≥ 300 Da), however, ESI proved to be the more ideal atmospheric pressure ionization source. A mobile phase consisting of 1% (w/w) ammonium trifluoroacetate in methanol and 0.1% (w/w) formic acid in water increased the sensitivity of the APCI method significantly. A step gradient was then used to separate simultaneously all 19 native protein amino acid enantiomers in less than 20 min using extracted ion chromatograms. Copyright © 2004 John Wiley & Sons, Ltd.