摘要
目的测定牡荆素的解离常数(pKa)。方法采用电导法测定电导率(κ),以科尔劳乌施经验公式计算无限稀释下苯酚钠的摩尔电导率(∧m∞)。结果30℃牡荆素的电离平衡常数(K)为8.77×10^-10。结论氯化钠溶液用于临床配制药物,pH为8.3时,85%的牡荆素以分子形式存在。
Objective To determine the dissociation constant(pKa)of vitexin.Methods Conductance method was used to determine the conductivity(κ),and Kohlrausch’s empirical formula was used to calculate the molar conductivity(∧m∞)of sodium phenolate under unlimited equilibrium release.Results The ionization equilibrium constant(K)of vitexin at 30℃was 8.77×10^-10.Conclusion In clinical medication,when the pH value of the drug dissolved in sodium chloride solution is 8.3,85%of vitexin exists in molecular form.
作者
李晓亮
张磊
牛海军
李光辉
LI Xiaoliang;ZHANG Lei;NIU Haijun;LI Guanghui(Hefei Seven Star Pharmaceutical Science and Technology Co.,Ltd.,Hefei,Anhui,China 230088;Anhui Provincial Institute for Food and Drug Control,Hefei,Anhui,China 230031)
出处
《中国药业》
CAS
2020年第15期26-28,共3页
China Pharmaceuticals
基金
国家科技重大专项课题[2017ZX09301025]。
关键词
牡荆素
电导法
解离常数
摩尔电导率
vitexin
conductance method
dissociation constant
molar conductivity
