title: Analysis of iron-phytosiderophore complexes in soil related samples: LC-ESI-MS/MS versus CE-MS.
abstract: Phytosiderophores (PS) form stable complexes with various transition metals. These ligands are exuded by the roots of graminacous plants as a mechanism for mobilizing and acquiring soil iron. To investigate iron mobilization and transport, a novel LC method in combination with ESI-MS/MS for the determination of three Fe(III)-complexes with mugineic acid (MA), 2'-epi-MA and 2'-deoxymugineic acid (DMA) has been developed. Liquid chromatographic separation was realized using a silica-based mixed-mode reversed phase/weak-anion exchange type stationary phase and a 50 mM ammonium acetate buffer, pH 6.5. Baseline separation of the two complex diastereomers Fe(III)-MA and Fe(III)-epi-MA could be achieved. ESI-MS/MS detection allowed for simultaneous quantification of the complexes and the free ligands. Limits of detection were determined to be 0.001 and 0.05 μM for DMA and Fe(III)-DMA, respectively. The analytical figures of merit of the novel method were evaluated and compared with a CE-ESI-MS method that we had published earlier. The LC-ESI-MS/MS method has been successfully applied to real samples derived from preliminary extraction experiments.
authors.affiliation: Department of Chemistry, University of Natural Resources and Life Sciences, BOKU-Vienna,  Vienna, Austria.
authors.forename: Madeleine
authors.initials: M
authors.lastname: Dell'mour
authors.forename: Walter
authors.initials: W
authors.lastname: Schenkeveld
authors.forename: Eva
authors.initials: E
authors.lastname: Oburger
authors.forename: Lisa
authors.initials: L
authors.lastname: Fischer
authors.forename: Stephan
authors.initials: S
authors.lastname: Kraemer
authors.forename: Markus
authors.initials: M
authors.lastname: Puschenreiter
authors.forename: Michael
authors.initials: M
authors.lastname: Lämmerhofer
authors.forename: Gunda
authors.initials: G
authors.lastname: Koellensperger
authors.forename: Stephan
authors.initials: S
authors.lastname: Hann
mesh_terms: D001383:Azetidinecarboxylic Acid / Q000031:analogs & derivatives / Q000737:chemistry; D002853:Chromatography, Liquid / Q000379:methods*; D005290:Ferric Compounds / Q000032:analysis* / Q000737:chemistry; D017262:Siderophores / Q000032:analysis* / Q000737:chemistry; D012987:Soil / Q000032:analysis*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000379:methods
chemical_list: D005290:Ferric Compounds; D017262:Siderophores; D012987:Soil; D001383:Azetidinecarboxylic Acid; C052864:2'-deoxymugineic acid; C052863:mugineic acid