Safavi Afsaneh, Tohidi Maryam
Department of Chemistry, Faculty of Sciences, Shiraz University, Shiraz 71454, Iran.
J Pharm Biomed Anal. 2007 May 9;44(1):313-8. doi: 10.1016/j.jpba.2007.02.020. Epub 2007 Feb 23.
The kinetic H-point standard addition method (HPSAM) was applied to the simultaneous determination of levodopa and carbidopa. The method was based on the difference in the rate of oxidation of these compounds with Cu(II)-neocuproine system and formation of Cu(I)-neocuproine complex at pH 5.5. The absorbance of the Cu(I)-neocuproine complex was monitored at 453 nm. Experimental conditions such as pH, reagent concentrations, ionic strength and temperature were optimized. Simultaneous determination of levodopa and carbidopa was performed in the range of 0.8-4 and 0.2-1.5 microg ml(-1), respectively. The proposed method was applied to the simultaneous determination of levodopa and carbidopa in pharmaceutical samples, and satisfactory results were obtained.
采用动力学H点标准加入法（HPSAM）同时测定左旋多巴和卡比多巴。该方法基于这些化合物在Cu（II）-新铜试剂体系中的氧化速率差异以及在pH 5.5时形成Cu（I）-新铜试剂络合物。在453 nm处监测Cu（I）-新铜试剂络合物的吸光度。对pH、试剂浓度、离子强度和温度等实验条件进行了优化。左旋多巴和卡比多巴的同时测定范围分别为0.8 - 4和0.2 - 1.5 μg ml⁻¹。该方法应用于药物样品中左旋多巴和卡比多巴的同时测定，获得了满意的结果。
