【摘要】 利用糖蛋白-凝集素的识别作用交替沉积伴刀豆球蛋白(ConA)与辣根过氧化物酶(HRP)制备酶自组装多层膜,用原子力显微镜(AFM)观测了自组装膜的表面形貌、表面粗糙度;AFM和椭圆偏振研究测定了自组装膜的厚度.结果表明,ConA和HRP膜厚分别为9.0和4.6nm,与两者的晶体衍射结果一致,说明生物识别自组装方法能很好地保持分子的原有形态.以亚甲蓝(MB)溶液为介体,用循环伏安法测定了表面修饰了三层(ConA/HRP)自组装膜的金电极对H2O2的电化学催化还原作用,在H2O2浓度为0.2～1.0mmol·L-1时,响应电流对H2O2浓度变化成线性,酶电极灵敏度为24.0mA·mol-1·L,表观米氏常数为4.2mmol·L-1.更多还原

【Abstract】 The multilayer films of horseradish peroxidase(HRP)were fabricated by layer-by-layer a ssembly of HRP and concanavalin A(Con A)through lectin-glycogen reaction.The surface topography and roughness were characterized by AFM.The thick ness of the films was studied by AFM an d ellipsometry.The thicknesses of the Con A and the HRP film are about 9.0and 4.6nm,respectively,which co rrespond to their X-ray diffraction data.It is demonstrate d that the shape of Con A and HRP molecu le was well retained during the assembly process.Cyclic voltammetry(CV)was used to test the electrochemical properties of the films.The enzyme electrode of three bilayers o f(Con A /HRP)films was sensitive for the reductio n of hydrogen peroxide in the methylene blue(MB )solution.The response current is pr oportional to the concentration of H 2 O 2 within the range of 0.2～1.0mmol ·L -1 .The sensitivity of the enzyme electrode is 24.0mA·mol -1 ·L and the apparent Michaelis constant is 4.2mmol ·L -1 .更多还原