高效毛细管电泳法同时检测饲料中七种防腐剂

Simultaneous determination of seven preservatives in feeds by high performance capillary electrophoresis

建立酸性条件下同时分离测定山梨酸(SA)、苯甲酸(BA)、脱氢乙酸(DHA)、对羟基苯甲酸甲酯(MP)、对羟基苯甲酸乙酯(EP)、对羟基苯甲酸丙酯(PP)、对羟基苯甲酸丁酯(BP)七种防腐剂的高效毛细管电泳法。本试验用甲醇:水=1:1(体积比)的混合液作为提取剂提取饲料样品中防腐剂;以40 mmol/l磷酸二氢钾(KH2PO4)和100 mmol/l十二烷基硫酸钠(SDS)的1:1体积比混合液(pH=4.00)作为缓冲液,采用高效毛细管胶束电动色谱法测定样品中七种防腐剂。该方法在19 min内实现了七种防腐剂的分离;SA、BA的线性范围分别为1～500μg/ml和3～500μg/ml,DHA、MP、PP、BP、PP的线性范围均为5～500μg/ml,线性相关系数≥0.999 5。SA、BA、DHA和四种对羟基苯甲酸酯类防腐剂的检测限分别为0.5、1.5、3.0、2.5μg/ml;样品平均回收率为80.8%～107.0%,相对标准偏差≤5.0%。该方法高效快速分离了多种防腐剂,并且可以应用到各种饲料样品的检测。

A method was developed for simultaneous determination of seven preservatives in the acid condition by high performance capillary electrophoresis, including sorbic acid （SA）, benzoic acid （BA）, dehydroacetic acid （DHA）, methyl hydroxybenzoate （MP）, ethyl hydroxybenzoate （EP）, propyl hydroxyben- zoate（PP） and butyl hydroxybenzoate（BP）. The feed samples were extracted by mixed solution of methanol and water （1 ： 1, v/v）. Then seven preservatives were determinated using the running buffer system of 40 mmol/l potassium dihydrogen phosphate and 100 mmol/1 SDS （1 ： 1, v/v; pH=4.00） by high performance capillary micellar electrokinetic chromatography. The analysis has accomplished within 19 rain. The lin- ear range was 1-500 μg/ml for SA, 3-500 Ixg/ml for BA, 5-500μg/ml for DHA, MP, EP, PP and BP, respectively. The correlation coefficient was upper to 0.9995. The detection limit of SA,BA,DHA and four parabens was 0.5, 1.5, 3, 2.5μg/ml, respectively, The average recoveries（n=5） for samples were between 80.8% and 107.0%, the relative standard deviation（RSD） was less than 5.0%. The method was fast and efficient separating multiple preservatives, and applied to detection of feed samples.