title: Assessment of CE-ICP/MS hyphenation for the study of uranyl/protein interactions.
abstract: Identification of uranyl transport proteins is key to develop efficient detoxification approaches. Therefore, analytical approaches have to be developed to cope with the complexity of biological media and allow the analysis of metal speciation. CE-ICP/MS was used to combine the less-intrusive character and high separation efficiency of CE with the sensitive detection of ICP/MS. The method was based on the incubation of samples with uranyl prior to the separation. Electrophoretic buffers were compared to select a 10 mM Tris to 15 mM NaCl buffer, which enabled analyses at pH 7.4 and limited dissociation. This method was applied to the analysis of a serum. Two main fractions were observed. By comparison with synthetic mixtures of proteins, the first one was attributed to fetuin and in a lesser extent to HSA, and the second one to uranyl unbound to proteins. The analysis showed that fetuin was likely to be the main target of uranyl. CE-ICP/MS was also used to investigate the behavior of the fetuin-uranyl complex, in the presence of carbonate, an abundant complexing agent of uranyl in blood. This method enabled association constants determination, suggesting the occurrence of both FETUA(UO2(2+)) and FETUA(UO2(2+))(CO3(2-)) complexes, depending on the carbonate concentration.
authors: CEA/DSV/iBEB/SBTN, Laboratoire d'Etude des Protéines Cibles, Bagnols sur Cèze Cedex, France.
authors: Thi-Ngoc Suong
authors: TN
authors: Huynh
authors: Institut de Chimie Séparative de Marcoule, Laboratoire de Chimie et Physico-chimie des Actinides, Bagnols-sur-Cèze cedex, France.
authors: Damien
authors: D
authors: Bourgeois
authors: CEA/DSV/iBEB/SBTN, Laboratoire d'Etude des Protéines Cibles, Bagnols sur Cèze Cedex, France.
authors: Christian
authors: C
authors: Basset
authors: CEA/DSV/iBEB/SBTN, Laboratoire d'Etude des Protéines Cibles, Bagnols sur Cèze Cedex, France.
authors: Claude
authors: C
authors: Vidaud
authors: CEA/DSV/iBEB/SBTN, Laboratoire d'Etude des Protéines Cibles, Bagnols sur Cèze Cedex, France.|CNRS, UMR 7265, CEA/DSV/iBEB, St. Paul Les Durance, France.
authors: Agnès
authors: A
authors: Hagège
mesh_terms: D002021:Buffers; D002352:Carrier Proteins / Q000378:metabolism*; D019075:Electrophoresis, Capillary / Q000379:methods*; D013058:Mass Spectrometry / Q000379:methods*; D011485:Protein Binding; D014501:Uranium / Q000378:metabolism*
chemical_list: D002021:Buffers; D002352:Carrier Proteins; D014501:Uranium
keywords: Capillary electrophoresis; Carbonate; Metalloproteomics; Uranium