盐析辅助分散液液微萃取毛细管电泳法测定口服液中甜味剂和防腐剂

Determination of sweeteners and preservatives in oral liquid by salting out-assisted dispersive liquid-liquid microextraction combined with capillary electrophoresis

目的 采用盐析辅助分散液液微萃取(SADLLME)-大体积样品堆积(LVSS)-毛细管电泳(CE)法测定阿斯巴甜、糖精、安赛蜜3种甜味剂以及苯甲酸、山梨酸2种防腐剂。方法 将待测溶液进行盐析液液微萃取处理后进行CE分析测定,设定电泳条件为:进样压力5 000 Pa,进样时间为120 s,正常极性下分离电压为20 kV,检测波长为214 nm,分离温度为25℃。结果 该方法在0.05~1.00μg/mL范围内线性关系良好,最低检测限为3~10 ng/mL。萃取重现性良好(RSD<10%,n=5)。待测组分富集倍数达到657.9~1 674.8,富集效果良好。将该方法应用于海藻口服液等几种口服液中甜味剂和防腐剂的含量测定,均获得了满意的结果。结论 实验表明使用微萃取与在线富集结合的手段更为高效、快速,能获得更高的富集倍数,成为提高毛细管电泳灵敏度的1种可靠方法。

Objective To determine aspartame, saccharin and acesamel as sweeteners and benzoic acid and sorbic acid as preservatives by salt-out assisted dispersive liquid-liquid microextraction(SADLLME)-mass sample stair(LVSS)-capillary electrophoresis(CE). Methods The solution was treated by salting-out liquid-liquid microextraction and CE analysis. The electrophoresis conditions were set as follows: injection pressure 5 000 Pa injection time 120 s, separation voltage 20 kV under normal polarity, detection wavelength 214 nm, and temperature 25 ℃. Results The linear range of the method was 0.05–1.00 μg/mL, and the minimum detection limit was 3–10 ng/mL. The extraction reproducibility was good(RSD<10%, n = 5). The online enrichment ratio of the components to be measured was 657.9–1 674.8 with the combination of online and offline,indicating a good enrichment effect. The method has been applied to the determination of sweeteners and preservatives in different kinds of oral liquids such as seaweed, and satisfactory results have been obtained.Conclusion The experiments showed that the combination of microextraction and on-line enrichment was more efficient and rapid, and could obtain higher enrichment ratio, which was a reliable method to improve the sensitivity of capillary electrophoresis.