针对2010年版中国药典规定的顶空气相色谱法测定空心胶囊中环氧乙烷残留量的干扰物问题,使用气相色谱-质谱(GC-MS)联用技术进行了系统的考察,发现干扰物主要来自实验用水中溶解的CO2,对实验用水在使用前加热煮沸即可有效地去除干扰.同时,选用RTX-WAX色谱柱,在柱温40℃,载气流量0.8 mL/min时分离效果和峰型最好.在此基础上对药典方法进行了改进,实验结果表明:环氧乙烷含量为0.21~12.67μg时呈良好的线性关系,相关系数r=0.999 9;最低检出限为0.03μg,加标回收率为98.6%~103.2%,相对标准偏差为0.7%~1.7%.
Distractors in the determination of the residual ethylene oxide in hollow capsules by the headspace gas chromatography in the Chinese Pharmacopoeia of 2010 edition was systematically studied by GC-MS.Interference source was examined and found that interfering substances mainly came from CO2 which dissolved in the experiment water and the boiled distilled water interference could be removed.Using RTX-WAX column in the column temperature of 40 ℃ and carrier gas flow 0.8 mL/min the ethylene oxide separated well and the peak pattern was preferably.The results showed that the concentration of ethylene oxide in the range of 0.21-12.67 μg had good linear relationship.The correlation coefficient was 0.999 9.The limit of detection was 0.03 μg/mL.The recoveries ranged from 98.6% to 103.2% and the relative standard deviation was from 0.7% to 1.7%.