药物酚磺乙胺在MnO₂/离子液体复合电极上的电化学行为研究及测定

目的: 制备 PF₆-MnO₂-CHIT/GCE修饰电极,研究酚磺乙胺(ETH)在该电极上的电化学行为及其测定方法。 方法: 循环伏安法和微分脉冲伏安法。 结果: ETH在 PF₆-MnO₂-CHIT/GCE上的循环伏安图上出现1对灵敏、可逆的氧化还原峰,其氧化峰电流响应是其在MnO₂-CHIT/GCE上的2.8倍,峰电位差降低到0.029 V,电子转移速率常数Ks=0.283 s^-1。ETH在 PF₆-MnO₂-CHIT/GCE上的微分脉冲伏安扫描峰电流与其浓度在5.0×10^-7~5.0×10^-4 mol·L^-1范围内呈良好的线性关系,检出限为5.0×10^-8 mol·L^-1。连续5次测定1.0×10^-5 mol·L^-1酚磺乙胺溶液的RSD为1.8%。 结论: 本法可靠、快捷、灵敏,可用于酚磺乙胺注射液中酚磺乙胺含量的电化学定量测定,结果满意。

Objective: To fabricate PF₆-MnO₂-CHIT/GCE modified electrode,the electrochemical behavior and determination of ethamsylate (ETH) on the electrode were investigated. Methods: Cyclic voltammetry and differential pulse voltammetry. Results: The cyclic voltammetry curves of ETH at PF₆-MnO₂-CHIT/GCE electrode present a pair of sensitive and reversible redox peaks.The peak current response at the proposed electrode enhances 2.8 folds higher than that at the MnO₂-CHIT/GCE,and the peak potential difference is down to 0.029 V,electron transfer rate constant was Ks=0.283 S^-1.The differential pulse voltammetry peak current of ETH in PF₆-MnO₂-CHIT/GCE showed good linear relationship in the range of ETH concentration of 5.0×10^-7-5.0×10^-4 mol·L^-1,with a detection limit of 5.0×10^-8 mol·L^-1.The relative standard deviation of 1.0×10^-5 mol·L^-1 ETH was 1.8% for 5 consecutive measurements. Conclusion: The proposed method can be applied in ETH electrochemical determination with fast speed,high sensitivity and satisfied results.