Determination of Vitamin U in Vitamin U Preparations by a Potentiometric Titration Method / 中国药师

ABSTRACT

Objective:To improve the determination method of vitamin U in vitamin U preparations. Methods: A potentiometric titration method was established for the determination of vitamin U and the results were compared with those of the manual titration method described in the current quality standard. Results:The determination results of vitamin U by the potentiometric titration method were affected by neither the excipients and the other components contained in the preparations,nor the precipitation produced in the ti-tration process. The recoveries for two types of vitamin U ( methylmethinine sulfonium chloride and s-methy-L-methionine iodide) were 99. 47%(RSD=1. 0%,n=9) and 100. 22%(RSD=1. 4%,n=9), respectively. The determination results of 6 samples from 3 dif-ferent companies detected by the method were basically consistent to those detected by the manual titration method described in the cur-rent quality standards with the relative deviation less than or equal to 0. 5%. Conclusion:The method is simple,accurate and reliable, and can be used for the quantitative determination of vitamin U in various vitamin U preparations.