以聚阳离子聚二烯丙基二甲基氯化铵(PDDA)为功能高分子,修饰了石墨烯氧化物(GO)并与之复合,通过还原反应,制备了PDDA功能化的石墨烯复合材料(PDDA-G)。该复合材料在水溶液中具有良好的分散性。采用层层自组装方法,以静电作用为自组装驱动力,将PDDA-G和辣根过氧化物酶交替组装,制备了石墨烯/酶纳米复合多层膜修饰电极。该酶生物传感器用于过氧化氢的测定时具有快速的安培响应。过氧化氢的线性范围为1.0~155.0 μmol·L-1,检出限为0.3 μmol·L-1。对50.0 μmol·L-1过氧化氢溶液连续测定8次,测定值的相对标准偏差为2.6%。方法应用于食品样品中过氧化氢的测定,测定结果与国家标准方法的测定值相符。

Polydimethyldiallylammonium chloride (PDDA) was used as functional polymolecules to modify oxide of graphene, and a composite material of PDDA-graphene (PDDA-G) was prepared by reduction. A dispersion of PDDA-G in water was easily prepared. By the electrostatic force, graphene-enzyme nanomultilayers modified electrode was fabricated by alternate self-assembling of PDDA-G and horseradish peroxidase. This modified electrode was used as an enzyme biosensor which displayed rapid amperometric response, when used in the determination of hydrogen peroxide. Linearity range of hydrogen peroxide was found between 1.0 μmol·L-1 and 155.0 μmol·L-1 with detection limit of 0.3 μmol·L-1. Precision of the method was tested at the concentration level of 50.0 μmol·L-1 hydrogen peroxide solution for 8 determination, value of RSD found was 2.6%. The proposed method was applied to the determination of H2O2 in food samples, giving results in consistency with the values obtained by the GB method.