气相色谱法同时测定中药糖浆剂中3种防腐剂含量

Simultaneous determination of preservatives content in Chinese herb syrups by gas chromatography

[目的]建立中药糖浆剂中苯甲酸、山梨酸、对羟基苯甲酸乙酯等3种常用防腐剂的同时测定方法。【方法】样品经甲醇溶解、超声提取、离心，采用大口径非极性毛细管色谱柱DB-1（30mx0．25mmＸ0．25μm）气相色谱法进行定性和定量分析，并探讨最佳实验条件。[结果]该方法的线性范围为山梨酸10～100μg／mL，苯甲酸10～100μg／mL；对羟基苯甲酸乙酯5—50μg／mL，其相关系数在0．9969-0．9979之间，方法最低检出限分别为1．2、1．8、0．7μg／mL，样品加样回收率为95．4％～103．7％，相对平均偏差为2．9％～3．7％。并成功应用该方法检测实际样品中的防腐剂。【结论】该方法简易可行，并能较好地分离上述3种化合物，具有分析时间短、抗干扰性好、定量准确等优点。

[Objective] To establish a method for determination of 3 preservatives, benzoic acid, sorbic acid and ethyl-paraben in Chinese herb syrups simultaneously by gas chromatography. ]Methods] The Chinese herb syrups sample was dissolved by methanol, extracted by ultrasonic and separated by packed column of DB-1 （30 mx0.25 mmx 0.25 μm）. [Results] The concentrations of 3 preservatives showed a positive correlation with the peak heights at 10- 100 μg/mL for sorbic acid, 10-100 μg/mL for benzoic acid and 5-50 Ixg/mL for ethyl-paraben. The correlative coefficients were 0.996 9-0.997 9. The detection limits were 1.2, 1.8 and 0.7 μg/mL respectively. The recovery rates were 95.4%-103.7%. RSDs were 2.9%-3.7%. [Conclusion] The present method mentioned above can perfectly separate these three loreservatives with some advantages, such as simple, accurate, sensitive and quick.