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Titolo:
Chiral resolution of D- and L-amino acids by tandem mass spectrometry of Ni(II)-bound trimeric complexes
Autore:
Zhang, DX; Tao, WA; Cooks, RG;
Indirizzi:
Purdue Univ, Dept Chem, W Lafayette, IN 47907 USA Purdue Univ W LafayetteIN USA 47907 Dept Chem, W Lafayette, IN 47907 USA
Titolo Testata:
INTERNATIONAL JOURNAL OF MASS SPECTROMETRY
fascicolo: 1-3, volume: 204, anno: 2001,
pagine: 159 - 169
SICI:
1387-3806(20010206)204:1-3<159:CRODAL>2.0.ZU;2-5
Fonte:
ISI
Lingua:
ENG
Soggetto:
FAST-ATOM-BOMBARDMENT; HOST-GUEST COMPLEXATION; GAS-PHASE; KINETIC METHOD; RECOGNITION; FAB; DISCRIMINATION; DISTINCTION; AFFINITIES; PRINCIPLES;
Keywords:
chirality; amino acids; tandem mass spectrometry; kinetic method; nickel complexes; clusters; enantiomeric excess;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Physical, Chemical & Earth Sciences
Citazioni:
40
Recensione:
Indirizzi per estratti:
Indirizzo: Cooks, RG Purdue Univ, Dept Chem, W Lafayette, IN 47907 USA Purdue Univ WLafayette IN USA 47907 W Lafayette, IN 47907 USA
Citazione:
D.X. Zhang et al., "Chiral resolution of D- and L-amino acids by tandem mass spectrometry of Ni(II)-bound trimeric complexes", INT J MASS, 204(1-3), 2001, pp. 159-169

Abstract

Mass-selected trimeric cluster ions, [Ni-11(A)(ref*)(2)-H](+), where A designates the analyte amino acid and ref* designates the chiral reference amino acid, undergo competitive collision-induced dissociation to yield two dimeric clusters with a branching ratio dictated by the stereochemistry of both the analyte and the reference. This branching ratio (R) is related, using the kinetic method, to an enthalpic term, Delta (NiBDE)-B-11, the difference between the formation enthalpies of the two dimeric clusters. Chiral resolution of (D)- acid (L)-amino acids is directly related to the relative stabilities of the two diastereomeric clusters formed by the dissociation ofthe Ni(II)-bound trimeric clusters. The dimeric product ions differ in enthalpy by only a few kilojoules per mole, but chiral recognition is achievedfor all 19 naturally occurring chiral amino acids, using appropriate reference amino acids. Because there is evidence that the dissociating trimeric dusters may exist in different isomeric forms, the proportion of analyte versus reference amino acids in the mixture was examined to study the effect of this ratio on the success of chiral recognition. The effect was found tobe negligible. This suggests that there is an equilibrium between these isomeric clusters, which is governed by thermochemical properties rather thanthe relative concentrations of the constituent amino acids. A linear correlation was observed between In(R) and enantiomeric compositions of the analyte as expected from the kinetic method treatment, acid the direct measurement of optical purity to within 3% enantiomeric excess was demonstrated. With this new chiral recognition technique, qualitative and quantitative chiral analysis of amino acids is achieved. (C) 2001 Elsevier Science B.V.

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Documento generato il 26/09/20 alle ore 10:46:28