黄芩苷在纳米MnO_2-离子液体修饰电极上的电化学性质及电分析方法研究  

Electrochemical Behaviour of Baicalin at Nano-MnO_2-Ionic Liquid Modified Electrode and Its Electroanalytical Application

作　　者：刘志敏[1] 曹艳艳[1] 黄柏生[1] 

机构地区：[1]河南工业大学化学化工学院,河南郑州450001

出　　处：《分析测试学报》2011年第1期76-80,共5页Journal of Instrumental Analysis

基　　金：河南省高校青年骨干教师基金资助项目(001135);河南省教育厅自然科学研究基金资助项目(2008B150006)

摘　　要：用疏水性离子液体1-丁基-3-甲基眯唑六氟磷酸盐（[BMIM]PF6）和纳米MnO2作修饰剂，通过壳聚糖（CHIT）的成膜效应，构置了玻碳修饰电极（【BMIM]PF6-MnO2-CHIT／GCE）。在Brinon—Robinson（B—R）缓冲液中研究了黄芩苷在修饰电极上的电化学行为，建立了测定黄芩胶囊中黄芩苷含量的新方法。黄芩苷在[BMIM]PF6-MnO2-CHIT／GCE上的循环伏安图出现一对灵敏、可逆的氧化还原峰，其峰电流响应是其在MnO2-CHIT／GCE上的2．6倍，峰电位差为0．062V，电子转移速率常数ks=0．258S。黄芩苷在[BMIM]PF6-MnO2-CHIT／GCE上的微分脉冲伏安扫描峰电流与其浓度的负对数在1．0×10^-91．0×10^-4mol／L范围内呈良好线性，检出限（S／N=3）为1．0×10^10mol／L。连续5次测定1．0×10^-8mol／L黄芩苷溶液的RSD为2．1％。该法用于黄芩苷药物的含量测定，加标回收率为95％～103％，结果满意。A new [ BMIM ] PF6 -MnO2 -CHIT/GCE modified electrode was fabricated via the chitosan（CHIT） fihning using hydrophobic ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate （ [ BMIM ] PF6 ） and nano-MnO2 as modifiers. In Britton - Robinson （ B - R） buffer, the electrochemical behavior of baicalin at [ BMIM ] PF6 - MnO2 - CHIT/GCE was studied, and a new method for the determination of baicalin in radix scutellariae was developed. The cyclic voltammetry curves of haicalin at [ BMIM ] PF6- MnO2- CHIT/GCE presented a pair of sensitive and reversible redox peaks. The peak current responsed at the proposed electrode was enhanced 2.6 folds higher than that at the MnO2 - CHIT/GCE, and the peak potential difference was 0. 062 V, the electron transfer rate constant ks was 0. 258 s^-1. The change of the oxidation peak current with baiealin concentration at [ BMIM]PF6 -MnO2 -CHIT/GCE was examined by differential pulse voltammetry. The calibration curve was linear in the concentration range of 1.0 × 10-9 - 1. 0× 10 5 mol/L with a detection limit （S/N=3） of 1.0× 10^10 mol/L. The relative standard deviation（n =5） of 1.0b 10-8 mol/L baicalin was 2. 1%. The method was applied in the determination of baicalin in samples with satisfactory results, and the spiked recoveries were in the range of 95% - 103%.

关 键 词：[BMIM]PF6 纳米MNO2 黄芩苷 循环伏安法 微分脉冲伏安法 

分 类 号：O657.1[理学—分析化学] TQ460.72[理学—化学]