摘要
研究了在用RP HPLC法测定有机酸时如何对流动相的酸度进行控制 ,给出了流动相最佳pH的选择通式 :色谱柱允许的最低 pH值≤pH≤pKa- 2 ;研究了流动相中甲醇、乙腈存在时对此通式的影响。用研究得出的结论选择了测定甲酸、乙酸、丙酸、丁酸和丙二酸、丁二酸、戊二酸、己二酸时的色谱条件 ,并且研究了每种酸在各自浓度范围内测定的线性关系、回归方程、相关系数以及相对标准偏差。实验显示 ,在选定的色谱条件下进行分析测试时 ,各种酸的线性相关系数r >0 9995 ,相对标准偏差RSD <0 90 %。
The pH values of the mobile phase which affect the chromatographic behavior of organic acids in RP HPLC have been studied It was considered that the problem of organic acids on an RP HPLC column was dissociation The equation for finding the optimum pH of mobile phase was pH limit of colunm ≤pH≤p K a-2 In addition the effects of contents of methanol and acetonitrile in mobile phase were studied By using the formula the mobile phases used for the analysis of organic monobasic acids—formic,acetic,propionic and butyric acid and of organic dibasic acids—propane diacid,butane diacid,pentane diacid and hexane diacid were proposed For the analysis of the monobasic acids, the wavelength of UV detector was set at 210 nm and the mobile phase was a mixture of phosphate buffer solution(15 mmol/L,pH 2 1) methanol(85∶15, V/V ) and at a rate of 1 5 mL/min and the column was Diamond C 18 , 150 mm×4 6 mm i.d. The average coefficient of correlation was 0 999?7 and RSD was less than 0 90% The mobile phase for organic dibasic acids was a mixture of phosphate buffer solution (20 mmol/L, pH 2 1) methanol(75∶25, V/V ) The other conditions were the same as for organic monobasic acids The average coefficient of correlation was 0 999?8 and RSD was less than 0 70%
出处
《色谱》
CAS
CSCD
北大核心
2001年第3期260-263,共4页
Chinese Journal of Chromatography
基金
西北大学校内基金!资助课题 ( 99NW 5 0 )
