title: Development of amino acid derivatization reagents for liquid chromatography electrospray ionization mass spectrometric analysis and ionization efficiency measurements.
abstract: Derivatization is one of the most common ways for improving chromatographic separation and sensitivity for LC-ESI-MS analysis. The aim of this work was to design new derivatization reagents for LC-ESI-MS analysis of amino acids which would (1) provide good reversed phase chromatographic separation, (2) most importantly, provide low detection limits, (3) be easily synthesized, (4) produce derivatives which are less susceptible to matrix influences and (5) have convenient derivatization procedure with stable derivatives suitable for automatization. In the current work two new LC-ESI-MS compatible derivatization reagents have been designed and synthesized, dibenzyl ethoxymethylene malonate (DBEMM) and benzyl ethyl ethoxymethylene malonate (EBEMM). The DBEMM meets all the goals set with instrumental detection limits as low as 1 femtomole for amino acids and 40 attomole for selenoamino acids.
authors.affiliation: Institute of Chemistry, University of Tartu, Ravila 14a, 50411 Tartu, Estonia. Electronic address: riin.rebane@ut.ee.
authors.forename: Riin
authors.initials: R
authors.lastname: Rebane
authors.affiliation: Institute of Chemistry, University of Tartu, Ravila 14a, 50411 Tartu, Estonia.
authors.forename: Toomas
authors.initials: T
authors.lastname: Rodima
authors.affiliation: Institute of Chemistry, University of Tartu, Ravila 14a, 50411 Tartu, Estonia.
authors.forename: Agnes
authors.initials: A
authors.lastname: Kütt
authors.affiliation: Institute of Chemistry, University of Tartu, Ravila 14a, 50411 Tartu, Estonia.
authors.forename: Koit
authors.initials: K
authors.lastname: Herodes
mesh_terms: D000596:Amino Acids / Q000032:analysis*; D056148:Chromatography, Reverse-Phase / Q000379:methods; D007202:Indicators and Reagents; D057230:Limit of Detection; D008314:Malonates / Q000138:chemical synthesis / Q000737:chemistry*; D019697:Onions / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods
chemical_list: D000596:Amino Acids; D007202:Indicators and Reagents; D008314:Malonates; C000599254:benzyl ethyl ethoxymethylene malonate; C000599250:dibenzyl ethoxymethylene malonate
keywords: Amino acids; Derivatization; Ionization efficiency; LC-ESI-MS; Matrix effects