title: A new metal chelate affinity adsorbent for cytochrome C.
abstract: We have prepared a novel metal-chelate adsorbent utilizing N-methacryloyl-L-histidine methyl ester (MAH) as a metal-chelating ligand. MAH was synthesized by using methacryloyl chloride and l-histidine methyl ester dihydrochloride. Spherical beads with an average diameter of 75-125 microm were produced by suspension polymerization of 2-hydroxyethyl methacrylate (HEMA) and MAH carried out in an aqueous dispersion medium. Then, Cu(2+) ions were chelated directly on the chelating beads. Cu(2+)-chelated beads were used in the adsorption of cytochrome c (cyt c) from aqueous solutions. The maximum cyt c adsorption capacity of the Cu(2+)-chelated beads (658.2 micromol/g Cu(2+) loading) was found to be 31.7 mg/g at pH 10 in phosphate buffer. The nonspecific cyt c adsorption on the naked PHEMA beads was 0.2 mg/g. Cyt c adsorption increased with increasing Cu(2+) loading. Cyt c adsorption capacity was demonstrated for the buffer types with the effects in the order phosphate > HEPES > MOPS > MES > Tris-HCl. Cyt c molecules could be adsorbed and desorbed five times with these adsorbents without noticeable loss in their cyt c adsorption capacity.
authors.affiliation: Department of Chemistry, Anadolu University, Eskişehir, Turkey.
authors.forename: Sibel
authors.initials: S
authors.lastname: Emir
authors.forename: Ridvan
authors.initials: R
authors.lastname: Say
authors.forename: Handan
authors.initials: H
authors.lastname: Yavuz
authors.forename: Adil
authors.initials: A
authors.lastname: Denizli
mesh_terms: D000327:Adsorption; D002614:Chelating Agents / Q000737:chemistry*; D002846:Chromatography, Affinity / Q000379:methods*; D003300:Copper / Q000737:chemistry*; D045304:Cytochromes c / Q000737:chemistry*; D004789:Enzyme Activation; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000737:chemistry; D006639:Histidine / Q000031:analogs & derivatives / Q000737:chemistry*; D008670:Metals / Q000737:chemistry; D008689:Methacrylates / Q000737:chemistry*; D008863:Microspheres
chemical_list: D002614:Chelating Agents; D004800:Enzymes, Immobilized; D008670:Metals; D008689:Methacrylates; C491950:N-methacryloyl-L-histidine methyl ester; D006639:Histidine; D003300:Copper; D045304:Cytochromes c