Determination of 1-aminocyclopropane-1-carboxylic acid and its structural analogue by liquid chromatography and ion spray tandem mass spectrometry.
Liquid chromatography coupled to ion spray tandem mass spectrometry was developed as a method for the simultaneous analysis of the amino acid 1-aminocyclopropane-1-carboxylic acid (ACC) and its structural analogue, cyclopropane-1,1-dicarboxylic acid (CDA). ACC and CDA fragmentation as well as optimization of MS parameters were investigated in positive ion mode. In selective reaction monitoring mode the protonated molecule [M+H]+ was selected as parent ion for both ACC and CDA, while the immonium ion from ACC and the [M+H-H2O]+ ion from CDA were selected, respectively, as product ions. In spite of the high selectivity of MS/MS among the 20 protein amino acids potentially present with ACC and CDA in the plant material analyzed, Glu and Thr can interfere with the signal of ACC. As a result, their chromatographic separation is necessary. This was achieved in less than 4 min by ion-pair reversed-phase chromatography with nonafluoropentanoic acid as ion-pair reagent. A linear response within a concentration range of 1-5 mg l(-1) was observed for this LC method and the detection limit was found to be 20 pmol for ACC and 150 pmol for CDA (using a 20-microl loop). This methodology was successfully applied to the detection of ACC in apple tissue.
Petritis
K
K
Institut de Chimie Organique et Analytique, CNRS UPRES-A, Université d'Orléans, France.
Dourtoglou
V
V
Elfakir
C
C
Dreux
M
M
D000598:Amino Acids, Cyclic / Q000032:analysis*; D002853:Chromatography, Liquid / Q000379:methods*; D005638:Fruit / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
D000598:Amino Acids, Cyclic; C023863:1-aminocyclopropane-1-carboxylic acid