左旋多巴片中左旋多巴的流动注射分析法

Spectrophotometric Determination of Levodopa in Levodopa Tablets by Flow Injection Analysis

在自行组装带微型计算机的流动注射分析仪上,以721型分光光度计为检测器,利用FeCl_3与左旋多巴的显色反应进行定量,建立了流动注射分析测定左旋多巴片中左旋多巴含量的新方法。最佳显色反应条件为0.0032mol/L FeCl_3-0.03mol/L HCl,检测波长728nm,左旋多巴线性范围50～1600μg/ml,检测限10μg/ml,进样频率100样次/h,方法简便、快速、可靠,回收率达97.88％～103.4％,相对标准偏差<3.2％。

A FIA method for the determination of levodopa in levodopa tablets was studied, employing FeCl3 as the chromagenic reagent. A microcomputer controlled flow injection analysis system coupled with spec-trophotometer was used. The sample solution was injected into the carrier stream, which was a solution containing 0. 0032 mol/L FeCl3-0. 03 mol/L HCl,and detected at 728 nm. A rate of measurements was 100 times per hour. The linear range was 50-1600 μg/ml and detection limit 10 μg/ml (r= 0.9992). The proposed method is simple, rapid and accurate. The average recoveries of levodopa in levodopa tablets were 97. 88% -103. 4% with their relative standard deviation less than 3.2%.