title: Graphene oxide-rare earth metal-organic framework composites for the selective isolation of hemoglobin.
abstract: Graphene oxide-La(BTC)(H2O)6 (H3BTC=1,3,5-benzenetricarboxylic acid) metal organic framework composites (LaMOF-GOn, n = 1-6, corresponding to the percentage of GO at 1, 2, 3, 4, 5, and 10%) are prepared through a simple and large-scale method at room temperature. The obtained composites are characterized by ATR-FTIR spectra, SEM, XRD, TGA, and N2 adsorption-desorption isotherm. The presence of GO significantly changes the morphologies of the composites from spindly rectangular rods to irregular thick blocks and increases their surface area from 14.8 cm(2) g(-1) (LaMOFs) to 26.6 cm(2) g(-1) (LaMOF-GO3), whereas at the same time, the crystalline structure of La(BTC)(H2O)6 is maintained. As a novel solid-phase adsorbent the LaMOF-GO composite exhibits outstanding adsorption properties for proteins. The strong hydrophobic interaction, especially π-π interaction between protein and the composite, is the main driving force for protein adsorption. In particular, highly selective isolation of hemoglobin (Hb) is achieved by using LaMOF-GO3 composite as sorbent in 4 mM B-R buffer containing 0.05 mol L(-1) NaCl at pH 8. The retained Hb could be effectively recovered with a 1 mM B-R buffer at pH 10, giving rise to a recovery of 63%. The practical applicability of the LaMOF-GO3 composite is demonstrated by the selective adsorption of Hb from human whole blood, and SDS-PAGE assays indicate that Hb could be selectively isolated with high purity from biological samples of complex matrixes.
authors.affiliation: Research Center for Analytical Sciences, College of Sciences, Northeastern University , Shenyang 110819, China.
authors.forename: Jia-Wei
authors.initials: JW
authors.lastname: Liu
authors.forename: Yue
authors.initials: Y
authors.lastname: Zhang
authors.forename: Xu-Wei
authors.initials: XW
authors.lastname: Chen
authors.forename: Jian-Hua
authors.initials: JH
authors.lastname: Wang
mesh_terms: D000327:Adsorption; D004591:Electrophoresis, Polyacrylamide Gel; D006108:Graphite / Q000737:chemistry*; D006454:Hemoglobins / Q000302:isolation & purification*; D008674:Metals, Rare Earth / Q000737:chemistry*; D009930:Organic Chemicals / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry
chemical_list: D006454:Hemoglobins; D008674:Metals, Rare Earth; D009930:Organic Chemicals; D010087:Oxides; D006108:Graphite