title: A new metal-chelated cryogel for reversible immobilization of urease.
abstract: Poly(2-hydroxyethyl methacrylate-co-glycidyl methacrylate) [poly(HEMA-GMA)] cryogel was synthesized by cryopolymerization technique at frozen temperature. Iminodiacetic acid (IDA) was then attached covalently to the cryogel as a chelating agent. Then, poly(HEMA-GMA)-IDA cryogel was chelated with Ni(II) ions and this novel metal affinity support was used for adsorption of urease from its aqueous solution. Urease adsorption experiments were carried out in a continuous system by using a peristaltic pump. Maximum urease adsorption onto poly(HEMA-GMA)-IDA-Ni(II) cryogel was found to be 11.30 mg/g cryogel at pH 5.0 acetate buffer and in 25 °C medium temperature. Urease adsorption capacity decreased with increasing ionic strength and increasing chromatographic flow rate. Adsorption kinetics of urease onto poly(HEMA-GMA)-IDA-Ni(II) cryogel was also investigated and it was found that Langmuir adsorption model is applicable for this adsorption study. This novel immobilized metal affinity chromatography support was used 10 times without any decrease at their adsorption capacity. It was also observed that urease enzyme was repeatedly adsorbed and desorbed without significant lost in enzymatic activity.
authors.affiliation: Koçarlı Vocational and Training School, Adnan Menderes University, Aydın, Turkey. muygun@adu.edu.tr
authors.forename: Murat
authors.initials: M
authors.lastname: Uygun
authors.forename: Begüm
authors.initials: B
authors.lastname: Akduman
authors.forename: Sinan
authors.initials: S
authors.lastname: Akgöl
authors.forename: Adil
authors.initials: A
authors.lastname: Denizli
mesh_terms: D000327:Adsorption; D002614:Chelating Agents / Q000737:chemistry*; D004789:Enzyme Activation; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000737:chemistry; D008689:Methacrylates / Q000737:chemistry*; D009532:Nickel / Q000737:chemistry*; D011109:Polymethacrylic Acids / Q000737:chemistry*; D014510:Urease / Q000737:chemistry*
chemical_list: D002614:Chelating Agents; D004800:Enzymes, Immobilized; D008689:Methacrylates; D011109:Polymethacrylic Acids; C042535:polyglycidyl methacrylate; C005044:hydroxyethyl methacrylate; D009532:Nickel; D014510:Urease