A facile method for improving the covalent crosslinking adsorption process of catalase immobilization

In this paper, we introduced a polydiol (mixture of 1,2-propanediol, 1,3-propanediol, and 2,3-butanediol) to improve the covalent crosslinking adsorption process of immobilized catalase onto chitosan beads. The adsorption behavior was investigated by means of adsorption kinetics and adsorption isotherm. The protein content in crosslinking agent required for approximately 45 min to reach the relative equilibrium, and the protein content in solution of the control group and the pretreated group were 6.63 μg/mL and 6.20 μg/mL, respectively. The maximum catalase adsorption capacity of the control group and the pretreated group were observed as 23.118 μg/g and 25.688 μg/g at pH 7.0, respectively. Temperature profiles showed that 40 °C was the ideal temperature for active domain of catalase, and the relative activity of pretreated group was 1.12 times higher than that of the control group. The Km value of the control group (67 mM) was higher than that of the pretreated group (54 mM). Thermal stability, operational stability, and the effect of surfactant on catalase adsorption were also explored in this study.