scholarly journals Electrochemical behavior of lansoprazole at a multiwalled carbon nanotubes-ionic liquid modified glassy carbon electrode and its electrochemical determination

2014 ◽  
Vol 79 (1) ◽  
pp. 39-52 ◽  
Author(s):  
Li-Hong Liu ◽  
Wei You ◽  
Xue-Mei Zhan ◽  
Zuo-Ning Gao

The electrochemical behavior of lansoprazole (LNS) has been investigated at a glassy carbon electrode (GCE) and the electrode modified by a gel containing multiwalled carbon nanotubes (MWCNTs) and an room-temperature ionic liquid (RTIL) of 1-Butyl-3-methylimidazolium hexafluorophosphate (BMIMPF6) in 0.10 M phosphate buffer solution of pH 6.8. It was found that an irreversible anodic oxidation peak with Epa as 1.060 V appeared at MWCNTs-RTIL/GCE. Under the optimized experimental conditions a linear calibration curve were obtained over the concentration range from 5.0 ?M to 0.20 mM by differential pulse voltammetry with the limit of detection (LOD, S/N = 3) as 0.28 ?M. In addition, the novel MWCNTs-RTIL/GCE was also characterized by the electrochemical impedance spectroscopy and the proposed method has been successfully applied in the electrochemical quantitative determination of LNS content in commercial tablet samples and the determination results could meet the determination requirement.

2012 ◽  
Vol 90 (6) ◽  
pp. 517-525 ◽  
Author(s):  
Youqin Liu ◽  
Xiuying Tian ◽  
Yun Yan ◽  
Yuehua Xu

Copper hydroxide (oxide) / multiwalled carbon nanotubes nanocomposite-modified glassy carbon electrode (Cuhydroxide/oxide/MWCNTs/GCE) was successfully prepared by a novel film plating / cyclic voltammetry (CV) method, which exhibited marked synergistic catalytic effects on the electro-oxidation of NO2–. The preparation process, impedance behavior, and surface morphology of Cuhydroxide/oxide/MWCNTs/GCE were investigated by CV, electrochemical impedance spectroscopy, and scanning electron microscopy (SEM), respectively. The optimum preparation and test conditions for the electrode to have high catalytic activity were acquired. The linear range between the anodic current (Δia, µA) and NO2– concentration (c, mmol L−1) was 1.0 × 10−4 to 14.0 mmol L−1, and the corresponding calibration curve was Δia = −0.1504 + 57.954c (R = 0.9990, n = 32) with a detection limit of 0.03 µmol L−1 (S/N = 3). The Cuhydroxide/oxide/MWCNTs/GCE prepared in the optimal conditions showed good stability, high selectivity, low detection limit, and quick response (<0.2 s) to NO2– in phosphate buffer (pH 5.29) at 0.78 V, which has been successfully applied to the determination of NO2– in pickled vegetables with satisfactory results.


Sign in / Sign up

Export Citation Format

Share Document