Aly F A, Belal F, el-Brashy A
Department of Analytical Chemistry, Faculty of Pharmacy, University of Mansoura, Egypt.
Pharm World Sci. 1993 Oct 15;15(5):208-11. doi: 10.1007/BF01880628.
A simple and sensitive polarographic method is described for the determination of metyrosine through treatment with nitrous acid. The different experimental parameters affecting the derivatization process, as well as the polarographic analysis were studied. The derivatization product was found to be reducible at the dropping mercury electrode over the whole pH range in Britton Robinson buffers. At pH 5, a well-defined diffusion-controlled cathodic wave was produced. The limiting current versus the concentration plot was linear over the range 8-80 mumol/l in the direct current mode with a detection limit of 0.2 mumol/l. The method was then applied to the determination of metyrosine capsules, and the results obtained were in good agreement with those given by the USP method.
描述了一种通过亚硝酸处理来测定甲酪氨酸的简单且灵敏的极谱法。研究了影响衍生化过程以及极谱分析的不同实验参数。发现衍生化产物在Britton Robinson缓冲液的整个pH范围内，于滴汞电极上均可被还原。在pH 5时，产生了明确的扩散控制阴极波。在直流模式下，极限电流与浓度的关系图在8 - 80 μmol/L范围内呈线性，检测限为0.2 μmol/L。该方法随后应用于甲酪氨酸胶囊的测定，所得结果与美国药典方法给出的结果吻合良好。
