纳米金/Nafion/多壁碳纳米管组装电化学传感器测定槐米中芦丁

目的:采用Nafion-多壁碳纳米管(MWNTs)修饰玻碳电极,通过恒电位法在其表面电沉积纳米Au,研制一种新型的、灵敏的芦丁电化学传感器,并用于实际样品中芦丁含量的测定。方法:运用电化学阻抗谱(EIS)和循环伏安法(CV)研究传感器在铁氰化钾-亚铁氰化钾体系中的电化学行为,以探究传感器的电化学性能。采用CV法研究芦丁在传感器表面的电化学行为,并优化影响传感器性能的多个因素。采用差分脉冲伏安法(DPV)对芦丁的含量进行测定。结果:当纳米Au的沉积电位为-0.25 V,沉积时间为20 s,缓冲溶液的pH为3.0,碳纳米管的用量为6μL时,芦丁检测的灵敏度最高。该条件下,芦丁浓度在5.0×10^-9~7.0×10^-7mol·L^-1与还原峰电流呈良好的线性关系,检出限为3.6×10^-9mol·L^-1。结论:该传感器制作简单,导电性能优良,稳定性好,对芦丁的检测具有较高的灵敏高和较低的检出限。将其用于槐米样品中芦丁含量的测定,回收率介于97.6%~104.4%,为芦丁含量的测定提供了一种新的方法,为中药材的质量控制提供了一种新的思路。

Detection of Rutin in Sophorae Immaturus Flos with Electrochemical Sensor Assembled with Gold Nanoparticles/Nafion/Multi-wall Carbon Nanotube

Objective:A new-type electrochemical sensor was developed by electrodepositing gold nanoparticle on the surface of glassy carbon electrode(GCE)modified by Nafion-multi-wall carbon nanotube(MWNTs)by the potentiostatic method,and used for the detection of rutin in practical samples.Method:The electrochemical properties of the sensor in potassium ferricyanide-potassium ferrocyanide system were studied by electrochemical impedance spectroscopy and cyclic voltammetric method,in order to explore the electrochemical performance of the sensor.The electrochemical behavior of rutin on the surface of the sensor was studied by the cyclic voltammetric method,and the factors affecting the performance of the sensor were optimized.The content of rutin was determined by differential pulse voltammetric methods.Result:The optimized conditions were-0.25 V of the deposition potential of gold nanoparticle,20 s of the deposition time,pH 3.0,and 6μL of 1 g·L^-1 carbon nanotube.Under the conditions,a good linear relationship between reduction peak current and rutin concentration was obtained from 5.0×10^-9 to 7.0×10^-7 mol·L^-1,and the detection limit was 3.6×10^-9 mol·L^-1.Conclusion:The developed sensor has a good electrical conductivity and stability,and is highly sensitive and simple for the detection of rutin,with a low detection limit.It has been successfully applied to the detection of rutin in Sophorae Immaturus Flos with the recoveries between 97.6%and 104.4%,which provides a new method for the determination of rutin and a new idea for the quality control of Chinese medicinal materials.