title: Recovering Ga(III) from coordination complexes using pyridine 2,6-dicarboxylic acid chelation ion chromatography.
abstract: Ion exchange chelation chromatography is an effective means to extract metals from coordination complexes and biological samples; however there is a lack of data to verify the nature of metal complexes that can be successfully analysed using such a procedure. The aim of this study was to assess the capability of pyridine 2,6-dicarboxylic acid (PDCA) to extract and quantify Ga(III) from a range of environments using standard liquid chromatography apparatus. The PDCA chelation method generated a single Ga(III) peak with a retention time of 2.55 +/- 0.02 min, a precision of <2% and a limit of detection of 110 microM. Ga(III) hydroxide complexes (highest stability constant 15.66) were used to successfully cross-validate the chelation method with inductively coupled plasma mass spectrometry. The PDCA assay extracted 96.9 +/- 1.2% of the spiked Ga(III) from porcine mucus and 100.7 +/- 2.7% from a citrate complex (stability constant 10.02), but only ca 50% from an EDTA complex (stability constant 22.01). These data suggest that PDCA chelation can be considered a suitable alternative to inductively coupled plasma mass spectrometry for Ga(III) quantification from all but the most strongly bound coordinated complexes i.e. a stability constant of <15.
authors.affiliation: King's College London, UK.
authors.forename: K
authors.initials: K
authors.lastname: Staff
authors.forename: M B
authors.initials: MB
authors.lastname: Brown
authors.forename: R C
authors.initials: RC
authors.lastname: Hider
authors.forename: X L
authors.initials: XL
authors.lastname: Kong
authors.forename: P
authors.initials: P
authors.lastname: Friden
authors.forename: S A
authors.initials: SA
authors.lastname: Jones
mesh_terms: D002852:Chromatography, Ion Exchange / Q000379:methods*; D056831:Coordination Complexes / Q000737:chemistry*; D005708:Gallium / Q000302:isolation & purification*
chemical_list: D056831:Coordination Complexes; D005708:Gallium