奎宁与氯冉酸的胶束增敏荷移反应及其测定

Spectrophotometric Determination of Quinine by Charge-Transfer Reaction Between Quinine and Chloranilic Acid with Micelle-Sensitized

提出了一种基于胶束增敏荷移反应测定奎宁的光度分析法。研究了在阳离子表面活性剂氯化十六烷基吡啶 (CPC)胶束体系中电子给体奎宁与电子受体氯冉酸之间的荷移反应产物的光谱性质。发现CPC对奎宁与氯冉酸的荷移反应络合物的光吸收有显著的增强作用 ,使络合物的表观摩尔吸光系数提高了 2 .5倍(λmax=5 2 0nm ,ε=3.6 4× 1 0 3 L·mol-1 ·cm-1 )。奎宁浓度在 2 0～ 80 0mg/L范围内符合比耳定律 ,r =0 9991。本方法用于片剂中奎宁含量的测定 ,其回收率为 97.3%～ 99.2 % ;5次测定的相对标准偏差为 1 .6 %～ 2 5 %。

A new spectrophotometric method for the determination of quinine has been developed based on the charge-transfer reaction with micelle-sensitized. The spectrum characteristics of charge-transfer complex formed between quinine as the donor and chloranilic acid as the acceptor in cetylpyridinium chloride (CPC) micellar system was studied. Experimental results show that the absorption of the complex is remarkably enhanced by CPC micellar system. The apparent molar absorptivity of quinine complex (epsilon=3.64x10(3) L.mol(-1).cm(-1) at 520 nm) was raised 3.5 times than that of non-micellar system. Beer's Low is obeyed from 20 to 800 mg/L quinin, r=0.9991. The recoveries are 97.3%-99.2%. The relative standard deviation is 1.6%-2.5% (n=5). The proposed method has been applied to the determination of quinine in tablets with satisfactry results.