Study on the Retention Behaviors of Eight Pyrazines by Reversed-Phase High Performance Liquid Chromatography
反相高效液相色谱法对八种吡嗪类化合物保留性能的研究

The separating condition of eight pyrazines by reversed-phase high performance liquid chromatography with methanol/water system as eluant has been studied on Spherisorb-C(18) column. The results showed that the capacity factor(k')of eight compounds decreases with the increase of concentration of methanol. When it is higher than 40% (V/V), the separation of the early peaks can not be achieved. When it is less than 40% (V/V),the retention time of the later eluted components is up to 30-45 minutes. Inorganic salts or micro amount of organic amine can improve the separation. In particular, the analytical time can be shortened obviously by adding triethylamine modifier in mobile phase. A mixture of methanol:0. 2mol/L HAc-NaAc buffer solution (pH 4. 5):triethylamine=40:59:1(V/V) was used as mobile phase with UV 254 nm detection. All components ,except 2, 3- and 2 , 5-dimethylpyrazines , were separated within 25 minutes.