Yotova L.Yaneva S.Marinkova D.Serfaty S.2024-07-102024-07-102024-07-102024-07-102013-09-041310-281810.5504/BBEQ.2013.0005SCOPUS_ID:84883260191https://rlib.uctm.edu/handle/123456789/282The sol-gel method was used to synthesise two groups of hybrid membranes from silica precursors: ETMS (ethyltrimethoxysilane) and MTES (methyltriethoxysilane), and cellulose derivatives. Peroxidase isolated from horseradish and tyrosinase isolated from mushrooms was immobilized by covalent immobilization. The kinetic parameters of the isolated enzymes, pH and temperature optimum were studied. The results of this study showed a higher relative and residual activity of the enzyme when immobilized on membranes containing cellulose acetate propionate with high molecular weight CAP/H. Membranes with the best parameters were used as carriers of the multienzyme peroxidase-tyrosinase system. An optical biosensor with an oxygen electrode was constructed. Potentially, the sensor could be used for monitoring of the environment, detecting phenols in wastewater, food stuff, and in medicine.enArticle