ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Immobilization of urease in poly(1-vinyl imidazole)/poly(acrylic acid) network

Mehmet Şenel, Agah Coşkun, M. Fatih Abasıyanık, and Ayhan Bozkurt

Department of Chemistry, Faculty of Arts and Sciences, Fatih University, B. Cekmece, Istanbul, 34500, Turkey

E-mail: msenel@fatih.edu.tr

Abstract: In this study, urease was immobilized in a polymer network obtained by complexation of poly(1-vinyl imidazole) (PVI) with poly(acrylic acid) (PAA). Preparation of the polymer network was monitored by FT-IR spectroscopy. Scanning electron microscopy (SEM) revealed that enzyme immobilization had a strong effect on film morphology. Proton conductivity of the PVI/PAA network was measured via impedance spectroscopy under humidified conditions. Values of the Michaelis-Menten constant (K _M) for immobilized urease were higher than for the free enzyme, indicating a decreased affinity of the enzyme to its substrate. The basic characteristics (pH_opt, pH_stability, T _opt, T _stability, reusability, and storage stability) of immobilized urease were determined. The results show that the PAA/PVI polymer network is suitable for enzyme immobilization.

Keywords: urease - immobilization - proton conductivity - polymer network

Full paper is available at www.springerlink.com.

DOI: 10.2478/s11696-009-0103-x

Chemical Papers 64 (1) 1–7 (2010)