【摘要】 结合氨基功能化离子液体修饰石墨烯(IL-GR)、纳米金(Au)等纳米材料的独特性质,以壳聚糖(CHIT)为交联剂,首先在玻碳电极表面固定IL-GR,然后吸附胶体金制得Au/IL-GR-CHIT复合膜,最后固定乙酰胆碱酯酶(AChE)制得新型有机磷检测酶传感器(AChE/Au/IL-GR-CHIT/GCE),并用于白菜样品中敌百虫农药的测定。采用透射电镜(TEM)对纳米材料进行了表征,循环伏安法(CV)和差示脉冲伏安法(DPV)研究了传感器的电化学性质。纳米复合物不仅为保持AChE的生物活性提供了适宜的微环境,并且对传感器性能的改善显示出强大的协同效应。在优化实验条件下,抑制率(A)与敌百虫浓度的负对数在2.0×10-10~1.0×10-6mol/L范围内呈良好的线性关系,检出限(S/N=3)为2.1×10-12mol/L。用于蔬菜中敌百虫含量的测定,回收率为97.5%~107.2%。更多还原

【Abstract】 According to the special properties of functionalized ionic liquid modified graphene(IL-GR) and nano-Au, IL-GR was firstly immobilized on the glass carbon electrode via chitosan(CHIT) cross-linking,and then a layer of nano-Au was adsorbed to form Au/IL-GR-CHIT composite film.Finally,acetylcholinesterase(AChE) was immobilized on the composite film by adsorption.A novel biosensor for detection of organophosphorus pesticides enzyme was developed,and used for the determination of trichlorfon.Different technologies were employed to study the construction process and the electrochemical properties of the biosensor.The results showed that the nanocomposite not only provided a biocompatible microenvironment to keep the bioactivity of AChE,but also exhibited a strong synergetic effect improving the sensing properties of biosensor.Linear relationship between inhibition percentage(A) and logarithm of concentration of trichlorfon was found in the range of 2.0 × 10-10-1.0 × 10-6mol/L,and the detection limit(S/N = 3) was calculated to be 2.1 × 10-12mol/L.The recoveries of trichlorfon in vegetable ranged from 97.5% to 107.2%.更多还原