尿素软膏的含量测定

Content Determination of Ointment Urea

目的建立测定尿素软膏中尿素含量的方法。方法采用电位滴定法,分别以甘汞电极和玻璃电极为参比电极和指示电极,以醋酐-苯(1∶1)为溶媒,用高氯酸滴定液(0.1mol·L^(- 1))滴定测定尿素软膏中尿素的含量。结果该方法△E/△V最大值为400m V,回归方程y=0.166807x-0.01075,r=0.9990,表明尿素含量在20mg^300mg范围内线性关系良好,平均回收率99.91%。结论该方法测定尿素软膏中尿素含量,结果准确可靠,简便易行,适合医院制剂的质量检查和控制。

OBJECTIVE Establish a method to determine the content of ointment urea. METHODS Determine by electrolytic titration for acetic anhydride and benzene（ 1∶ 1） to solvent and take calomel and glass electrode as reference and indicator electrode respectively,titrated by perchloric acid titrant（ 0. 1mol · L^（-1））. RESULTS The max of △E / △V was 400 m V and the regression equation was y = 0. 166807x-0. 01075,r = 0. 9990. It indicated the urea within the range of 20 mg ~ 300 mg has a good linear relationship. The average recovery rate was 99. 91%.CONCLUSION This method established to determine the content of urea is accuracy,reliable and simple. It is suit for quality inspection and control of hospital preparation.