毛细管电泳法检测饮料中的防腐剂

Detection of Preservatives in Beverages Through Capillary Electrophoresis

建立了毛细管电泳同时测定山梨酸、对羟基苯甲酸甲酯、对羟基苯甲酸乙酯、对羟基苯甲酸丙酯4种防腐剂的分析方法.以20mmol/L硼酸-硼酸钠(pH值10.0)为缓冲液,在有效长度为41cm、内径为50μm的石英毛细管中,当分离电压为15kV时,4种防腐剂9min内完全分离.在该条件下,分析物的峰面积与其质量浓度在10~1 000mg/L范围内呈良好的线性关系,回收率范围为95.4%~103.7%,多次测定结果的相对标准偏差小于4.5%.实验表明,该方法应用于饮料中山梨酸、对羟基苯甲酸乙酯和对羟基苯甲酸丙酯的分离检测时,简单快速且结果可靠.

A method for simultaneous detection of sorbic acid,methyl-p-hydroxybenzoate,ethyl-phydroxybenzoate,propyl-p-hydroxybenzoate through capillary electrophoresis was developed.With the composition of 20 mmol/L H_3BO_3-Na_2B4O_7（pH 10.0）as the buffer and in a capillary with an effective length of 41 cm and an inner diameter of 50μm,four kinds of preservatives were separated at a voltage of 15 kV within 9 min.Under these conditions,the analyte peak area was linearly proportional to its concentration within the range of 10~1 000 mg/L,the recovery was 95.4%~103.7%,and the relative standard deviation was less than 4.5%.The experiments show that this method is a desirable approach for the analysis of preservatives in beverage.