过硫酸钾存在下极谱催化波法测定氯胺酮

Determination of ketamine based on its polarographic catalytic wave in presence of persulfate

目的:建立一种简便、灵敏的测定氯胺酮(KET)新方法。方法:基于氧化剂存在时 KET 产生的极谱催化波,用线性扫描极谱法快速测定 KET。结果:在1.46×10^(-2)mol·L^(-1)Britton-Robinson(pH 2.09)支持电解质中,KET 于-1.44V(vs.SCE)处产生1个还原波。引入过硫酸钾后,该还原波峰电流增加约10倍,峰电位基本不变,产生一极谱平行催化波。其二阶导数峰峰电流与 KET 的浓度在1.0×10^(-9)～1.0×10^(-7)mol·L^(-1)范围内呈线性关系(r=0.9995,n=11),检出限为4.0×10^(-10)mol·L^(-1)。结论:该方法可用于药剂中 KET 含量的测定。

Objective：A novel simple and sensitive polarographic method for the determination of ketamine （KET） was presented. Methods：The catalytic wave of KET in the presence of K2 S2O8 was used for improving the analytical sensitivity. The rapid determination of KET has been carried out by linear scanning polarography. Results：The reduction wave of KET appeared at ca. - 1.44 V（vs. SCE） in 1.46×10^-2 mol· L^-1 Britton - Robinson （ pH 2. 09） supporting electrolyte,which was ascribed to the reduction of carbonyl group. In the presence of 0. 010 mol·L^-1 K2S2O8 ,the reduction wave was catalyzed to produce a parallel catalytic wave. The peak current of the catalytic wave was ten times higher than that of the corresponding reduction wave. The peak current of the catalytic wave was rectilinear to KET concentration in the range from 1.0×10^-9 to 1.0×10^-7 mol·L^-1 （r =0. 999 5 ,n = 11 ）. The detection limit was 4.0×10^-10mol·L^-1. Conclusion：The proposed method can be used for the direct determination of KET in pharmaceuticals without preliminary separation.