基于石墨烯/纳米金/壳聚糖复合膜固定化酶的有机磷生物传感器

将乙酰胆碱酯酶(AChE)固定到还原态氧化石墨烯(rGO)/纳米金(Au NPs)/壳聚糖(CS)复合膜修饰的玻碳电极表面,制备了高灵敏度的电化学生物传感器,用于有机磷农药的检测。由于rGO具有较大的比表面积和良好的导电性,复合材料不仅为保持AChE的生物活性提供了良好的生物相容环境,而且rGO/Au NPs的协同作用也提高了传感器的灵敏度。CS/SiO2复合溶胶-凝胶网格状的结构为酶的固定化提供了良好的载体。农药抑制率与乐果浓度的负对数在0.1~10.0ng/mL范围内呈线性关系,检出限为0.02ng/mL(S/N=3)。

A organophosphates Biosensor Based on RGO/AuNPs /CS composite membraneImmobilized Enzyme

A highly sensitive organophosphates (OPs) electro-biosensor was developed by immobilizing acetylcholinesterase (AChE) to graphene(RGO)/gold nanoparticles (AuNPs)/ chitosan (CS)composite on glass-carbon electrode. Because of the higher specific surface area and high conductivity of RGO, composite material not only provided a biocompatible environment to keep the bioactivity of AChE, but also RGO/AuNPs exhibited a strong synergetic effect on improving the sensing properties of OPs. CS/SiO₂ sol-gel offered a good supporter to enzyme because of its meshy structure. The linear relationship between the inhibition of rogor and its negative logarithm of concentration was found in the range of 0.1~10.0 ng/mL, with a detection limit of 0.02 ng/mL ( S/N= 3).