Identification and chromatographic separation of antimony species with α-hydroxy acids

The ability of α-hydroxy acids to complex with SbIII and SbV has been established in hydride generation atomic absorption spectrometric determinations of SbIII and solvent extraction techniques. The nature of this complexation with SbV has yet to be rigorously investigated. NMR, electrospray ionisation mass spectrometry and HPLC–ICP-AES methods have been developed to confirm the existence of these complexes in aqueous media and to determine their molecular masses based on a mole-ratio method. It is shown that anion-exchange chromatography can be used to separate mixtures of Sb(OH)x(L)n complexes, [L = citric, DL-malic, lactic or (±)-mandelic acid], where n = 6 – x.