Immobilization of enzyme preparations from Raphanus sativus L. var. niger on natural bentonite and bentonite modified by phosphate ions

Resumo

The changes in the mechanism and the selectivity of binding of the components from the enzyme preparation from Raphanus sativus L. var. niger adsorbed on both the natural bentonite and bentonite modified by phosphate ions are proved by several physical and chemical methods. The influence of the amphoterity of the acid–base properties of the support surface on the enhancement of the activity of the immobilized enzyme due to the lack of strong links with the iron- and zinc-containing molecules was established. The conditions of reducing the inactivation rate of the redox-active enzyme by covalent binding of molecule fragments on the surface of modified bentonite are shown. The observed significant reduction in the rate of inactivation of the oxidizing activity of the resulting composite could allow to consider it to be a promising base for a redox-sensor design.