摘要
研究了一种采用纳米四氧化三铁(Fe3O4)、壳聚糖(Chit)和石墨烯纳米材料(GR)复合膜修饰的乙酰胆碱酯酶(ACh E)生物传感器(NF-ACh E/Chit-Fe3O4/GR/GCE)用于毒死蜱农药的检测。该修饰电极的纳米复合膜结合了纳米四氧化三铁独特的吸附和生物相容性、壳聚糖优异的粘合性能以及石墨烯纳米材料大的比表面积和高的电子传递性能的优点,为乙酰胆碱酯酶提供一个良好的结合界面。通过循环伏安法、交流阻抗谱和方波伏安法研究发现新型修饰电极的电化学性能得到较大提高。在最优检测条件下,方波伏安法测定发现农药的抑制率与毒死蜱浓度在0.05μg/L^4.5μg/L范围内呈现良好的线性关系,线性相关系数0.997,最低检出限为0.02μg/L(S/N=3)。将该新型生物传感器用于检测蔬菜样品中毒死蜱的含量,表现出良好的稳定性和优异的检测精度。
Ferroferric oxide（Fe3O4） nanoparticles, chitosan（Chit）, and graphene（GR） composite films and Nafion（NF） solution were used to modify the glassy carbon electrode（GCE） in order to prepare an acetylcholinesterase（ACh E） amperometric biosensor（NF-ACh E/Chit-Fe3O4/GR/GCE） for the detection of chlorpyrifos pesticide. This modified electrode combined the unique absorbability and biocompatibility of Fe3O4 nanoparticles, the excellent adhesiveness of chitosan, and the large specific surface area and excellent electron transport properties of graphene nanomaterials for providing a good binding interface for ACh E. The results of cyclic voltammetry, alternating current（AC） impedance spectroscopy, and squarewave voltammetry showed that the electrochemical properties of the newly modified electrode were greatly improved. Under optimum conditions, the results from squarewave voltammetry revealed that the inhibition rates on ACh E activity had a good linear relationship with chlorpyrifos concentrations in the range from 0.05 μg/L to 4.5 μg/L; the linear correlation coefficient was 0.997 and the detection limit was 0.02 μg/L（S/N = 3）. Finally, this proposed biosensor was applied to determine the chlorpyrifos content in vegetable samples, and it was found that it showed excellent reproducibility and accuracy.
出处
《现代食品科技》
EI
CAS
北大核心
2016年第2期276-282,共7页
Modern Food Science and Technology
基金
高等学校博士学科点专项科研基金(20120008110033)
关键词
电化学
有机磷农药
生物传感器
石墨烯
纳米四氧化三铁
electrochemistry
organophosphorus pesticides
biosensor
graphene
ferroferric oxide nanoparticles
