离子液体修饰膨胀石墨电极测定利多卡因注射剂中的2,6-二甲基苯胺

摘要

以离子液体苯丙酮吡啶六氟磷酸盐（[PaPy]PF6）作为修饰剂与膨胀石墨粉混合,成功制备出离子液体修饰膨胀石墨碳糊电极( IL-EGPE)。在pH=6.86 PBS缓冲溶液条件下,采用线性扫描溶出伏安法（LSSV）研究2,6-二甲基苯胺（DMA）在IL-EGPE上的电化学行为,建立利多卡因注射剂中杂质含量分析的新方法。实验结果表明,DMA在0.700 V附近出现一个很明显的还原峰,在一定浓度范围内,峰电流与DMA的浓度呈良好的线性关系,其线性范围为1.6×10-6~1.52×10-5 mol/L,相关系数r=0.9994,回收率为95.6﹪~106.3﹪；该法操作简便、灵敏,可用于测定盐酸利多卡因注射液中的杂质2,6-二甲基苯胺的含量。%A Ionic liquid modified expanded graphite paste electrode (IL-EGPE) was constructed by blending pro-piophenone hexafluorophosphate ([PaPy]PF6) and expanded graphite. Linear sweep stripping voltammetry(LSSV)was used to record the electrochemical behavior of 2,6-methyltoluidine (DMA) in pH=6.86 PBS buffer solution. This method might be a new approach for determination of impurity in lidocaine hydrochloride injection. The results showed that DMA exhibited a reduction peak at 0.700 V. The increase of current intensity was proportional to DMA concentration in a linear range of 1.6×10-6 to 1.52×10-5 mol/L with correlation coefficient r=0.9994. This simple and sensitive method was also applied to detect concentration of DMA in lidocaine hydrochloride injection solution.