固定化辣根过氧化酶的壳聚糖/二氧化硅杂化膜的制备及表征

Preparation and Characterization of Chitosan/Silica Hybrid Film Immobilizing Horseradish Peroxidase

利用生物相容性良好的天然高分子聚合物壳聚糖(CS)与四乙氧基硅烷(TEOS)通过原位溶胶-凝胶法制备壳聚糖／二氧化硅有机无机杂化复合膜,用杂化膜对辣根过氧化酶进行固定,用红外光谱法、扫描电镜法对膜进行了表征。以金电极和固定化酶膜构建过氧化氢生物传感器,并用循环伏安法和计时电流法对传感器的特性进行了研究。结果表明,用于研制固定化酶生物传感器时,杂化膜不仅对底物的响应时间快(小于10s),而且能较好地保持酶的催化活性。求得酶促催化反应的表观米氏常数为0.87mmol／L。

A new type of organic-inorganic hybrid film was prepared by in_situ sol-gel with natural polymer chitosan(CS)with good biocompatibility and tetraethyl orthosilicate(TEOS),and characterized by fourier transform infrared spectroscopy(FT-IR)and scanning electron microscope(SEM).The hyˉbrid film was used to immobilize horseradish peroxidase(HRP)on the surface of a gold electrode to conˉstruct a hydrogen peroxide biosensor whose performance was investigated by cyclic voltammetry and chronoamperometry.The results show that the biosensor fabricated with hybrid film has a fast response time for substrate(less than10s)and a good ability retaining the activity of enzymes.The apparent Michaelis-Menten constant was found to be0.87mmol/L.