A highly sensitive amperometric sulfadiazine sensor fabricated by electrochemical deposition of poly(cobalt tetraaminophthalocyanine) (poly(Co II TAPc)) on the surface of a multi-walled carbon nanotubes-Nafion (MWCNTs-Nafion) modified electrode is described.This electrode showed a very attractive performance by combining the advantages of Co II TAPc,MWCNTs,and Nafion.Compared with the bare glassy carbon electrode (GCE) and the MWCNTs-Nafion modified electrode,the electrocatalytic activity of poly(Co II TAPc)-coated MWCNTs-Nafion GCE generated greatly improved electrochemical detections toward sulfadiazine including low oxidation potential,high current responses,and good anti-fouling performance.The oxidation peak currents of sulfadiazine obtained on the new modified electrode increased linearly while increasing the concentration of sulfadiazine from 0.5 to 43.5 μmol/L with the detection limit of 0.17 μmol/L.
A rapid and practical method for direct detection of lisinopril in anion exchange chromatography（AEC） has been developed with integrated pulsed amperometric detection（IPAD）.Dionex AS 18（250 mm×2 mm） and AG 18（50 mm×2 mm） columns and 40 mmol/L NaOH solution were used for separation.Multi-step potential waveform parameters were optimized to maximize the signal-to-noise ratio（S/N）.Utilizing the optimized waveform,the repeatability（intra-day） precision and intermediate（inter-day） precision were obtained with relative standard deviation（RSD） of 0.74,0.93,respectively.The limit of quantification（LOQ） and limit of detection（LOD） were found to be 0.37,0.12ng/mL,respectively,with the correlation coefficient of 0.9998 over concentration range 0.01-1μg/mL.The present method was successfully applied to the determination of lisinopril in human plasma.The recoveries of plasma sample spiked by 0.2μg/mL,0.8μg/mL lisinopril were 98.31-103.23%with RSD of 1.41%, 0.61%,respectively.
Yu Xiu LiuDan ShouMei Lan ChenZhi Dong ChenPei Min ZhangYan Zhu
