变色酸光度法测定对羟基苯海因

SPECTROPHOTOMETRIC DETERMINATION OF p HYDROXYPHENYLHYDANTOIN WITH CHROMOTROPIC ACID

利用变色酸光度法测定对羟基苯海因。将０２％的变色酸浓硫酸溶液作为显色剂加入试样中，于１００℃下加热反应１０２０ｍｉｎ，４２３ｎｍ处测定其吸光值。该法检测对羟基苯海因含量准确、可靠，测定范围在０．０６．０ｍｇ／Ｌ之间具有良好的线性关系，相关系数为０．９９９６，回收率为９７．９％１０１．３％，且不受对羟基苯海因经乙内酰脲酶转化生成的Ｄ对羟基苯甘氨酸的干扰，该法简单、迅速且具有良好的稳定性和重复性。

A simple and rapid method for spectrophotometric determination of p hydroxyphenylhy dantoin with chromotropic acid has been reported. In the experiment, an indicating solution of 0.2% chromotropic acid in concentrated sulfuric acid was added to the p hydroxyphenylhydantoin sample solution and the resulting mixture was heated at 100℃ for 10￣20 min, then the absorbance of the formed solution was measured at 423 nm. The results measured were accurate and reliable and had a good linear calibration curve in the range of 0.0￣6.0 mg/L. The correlation coefficient and the recovery were 0.9996 and 97.9%￣101.3%, respectively. The determination could effectively avoid the interference of p hydroxyphenylglycine which was produced by hydantoinase from p hydroxyphenylhydantoin and also had good stablility and duplicity.