title: Identification of the tri-Al tricitrate complex in Plantago almogravensis by hydrophilic interaction LC with parallel ICP-MS and electrospray Orbitrap MS/MS detection.
abstract: The identification of the ligands binding Al is essential to understand the mechanisms by which plants detoxify Al internally. However, studies concerning the speciation of Al have been frustrated by its complex chemistry. This work describes the identification of the tri-Al tricitrate (Al3cit3) complex in Plantago almogravensis, encompassing an integrated mass spectrometry approach based on hydrophilic interaction liquid chromatography (HILIC) and parallel detection by ICP-MS and ESI-MS/MS. This work also reports that both Al and Fe are bound by tricitrate, sometimes simultaneously, and the consequences of this finding are discussed. Of the complexes separated by size exclusion chromatography, Al3cit3 is the most stable occurring in P. almogravensis as it was the only one recovered after HILIC. This approach provided new information on the mechanism of Al detoxification in P. almogravensis, namely that Al is bound by the organic acid citrate and that the relative concentration of the detected complexes is affected by the organ type and internal Al concentration, and has potential for studying the speciation of Al in less tolerant plants.
authors.affiliation: IBB-CGB, Faculty of Sciences and Technology, University of Algarve, Campus de Gambelas, 8005-139 Faro, Portugal.
authors.forename: Tomás
authors.initials: T
authors.lastname: Grevenstuk
authors.forename: Paulina
authors.initials: P
authors.lastname: Flis
authors.forename: Laurent
authors.initials: L
authors.lastname: Ouerdane
authors.forename: Ryszard
authors.initials: R
authors.lastname: Lobinski
authors.forename: Anabela
authors.initials: A
authors.lastname: Romano
mesh_terms: D000535:Aluminum / Q000737:chemistry*; D002850:Chromatography, Gel; D002853:Chromatography, Liquid / Q000379:methods*; D019343:Citric Acid / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D007501:Iron / Q000737:chemistry; D013058:Mass Spectrometry / Q000379:methods*; D009942:Organometallic Compounds / Q000032:analysis* / Q000737:chemistry / Q000302:isolation & purification; D010943:Plantago / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods
chemical_list: D009942:Organometallic Compounds; D019343:Citric Acid; D000535:Aluminum; D007501:Iron