Dye derived and metal incorporated affinity poly(2-hydroxyethyl methacrylate) membranes for use in enzyme immobilization

✍ Scribed by Yakup Arıca, M.; Denizli, Adil; Baran, Türker; Hasırcı, Vasıf

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 227 KB
• Volume: 46
• Category: Article
• ISSN: 0959-8103
• DOI: 10.1002/(sici)1097-0126(199808)46:4<345::aid-pi36>3.0.co;2-7

✦ Synopsis

Microporous poly(2-hydroxyethyl methacrylate) (PHEMA) membranes were prepared by UV-initiated photopolymerization of HEMA in the presence of an initiator (a,a@-azobisisobutyronitrile, AIBN). An affinity dye Cibacron Blue F3GA (CB) was attached covalently and then Fe3ions incorporated. The PHEMA-CB and PHEMA-CB-Fe3membranes derived were used for adsorption of glucose oxidase (GOD). The adsorption capacities of these membranes were determined under conditions of di †erent pH and with di †erent concentrations of the adsorbate in the medium. The adsorption phenomena appeared to follow a typical Langmuir isotherm. The glucose oxidase adsorption capacity of the Fe3incorporated membrane (87 lg cm~2) was greater than that of the dye-derived membrane (66 lg cm~2). Non-speciÐc adsorption of the glucose oxidase on the PHEMA membranes was negligible. The values for K m both immobilized glucose oxidase PHEMA-CB-GOD (8É3) and PHEMA-CB-Fe3-GOD (7É6) were higher than that of the free enzyme (6É2 mM). Optimum reaction pH was 5É5 for the free and 6É0 for both immobilized preparations. The optimum reaction temperature of the adsorbed enzymes was 5¡C higher than that of the free enzyme and was signiÐcantly broader. After 15 successive uses the retained activity of the adsorbed enzyme was 87%. It was observed that enzymes could be repeatedly adsorbed and desorbed on the derived PHEMA membranes without signiÐcant loss in adsorption capacity or enzymic activity.

1998 SCI.