纳米银/石墨烯修饰电极测定青蒿素

A Glassy Carbon Electrode Modified with Graphene and Silver Nanoparticles for Determination of Artemisinin

本文建立一种新型的青蒿素传感器。首先,在玻碳电极上滴涂氧化石墨,通过电化学方法将氧化石墨还原为石墨烯,然后,在石墨烯上沉积纳米银得到石墨烯/纳米银修饰电极,它作为检测青蒿素的电化学传感器。用此电极对青蒿素进行测定,并通过循环伏安法、差分脉冲伏安法、交流阻抗法等研究其电化学行为。该修饰电极在测定青蒿素溶液时,表现出较正的还原电位和较大的峰电流等优势;对其实验条件如电解质溶液的p H、应用电势等进行了探查,该电化学传感器在青蒿素溶液浓度范围为1.0×10^-8-3.0×10^-5mol/L时与其还原峰电流呈现良好的线性关系,最低检出限为1.2×10^-9mol/L（S/N=3）。此外,对该传感器的稳定性和重现性等也进行了研究,获得令人满意的结果。

In this work, a novel artemisinin sensor was developed. Graphite oxide was coated and reduced to graphene （Gr） on a glassy carbon electrode （GCE） by electrochemical method. Then, Ag nanoparticles （AgNPs） were deposited on the above electrode to fabricate AgNPs/graphene modified electrode （AgNPs/Gr/GCE） , which was denoted as the electrochemical sensor of artemisinin. The electrochemical behaviour of the modified electrode was studied by cyclic voltammetry, differential pulse voltammetry, electrochemical impedance spectroscopy, and so on. The modified electrode displays excellent performance in the electrochemical reduction of artemisinin for showing more positive reduction peak potential and high reduction peak currents. The effects of the experimental variables on the determination of arteminin such as solution pH and applied potential were investigated for optimum analytical conditions, the electrochemical sensor exhibited linear response to artemisinin in the concentration ranges from 1. 1×10 ^-8 mol/L to 3, 0× 10 ^-4 mol/L, with a detection limit of 1.2 × 10＆ -9mol/L （ S/N of 3 ）. In addition, the stability and reproducibility of this sensor was also evaluated and gave satisfactory results.