饮料中苯甲酸的含量在溶胶-凝胶气相色谱毛细管柱上的直接测定

溶胶-凝胶柱是一种新型色谱柱，具有耐高温、分离效果佳、重现性好、制作工艺简单等特点．采用新型的溶胶一凝胶毛细管气相色谱柱可直接对饮料中的苯甲酸进行测定，而无需将苯甲酸衍生化，避免了衍生过程带来的误差、苯甲酸在该色谱柱上的峰形尖锐而又对称，无拖尾，分离效果极佳．以邻苯二甲酸二乙酯为内标，对几种不同品牌的饮料中的苯甲酸直接进行了定量测量．此方法测量的相对标准偏差为1.15％；回收率为99．7％．测量准确可靠，方法简便易行．

The Direct Determination of Benzoic Acid in Beverage by Gas Chromatography on a Sol-Gel Coated PDMS capillary Column

Sol gel column is a new type of chromatographic column with high temperatures tolerance, excellent separation and repeatability. The technological process for the developing of the column is relatively simple. The direct determination of benzoic acid in beverage can be carried out on the sol gel capillary column for gas chromatography without derivatization, and so the error in derivatization can be avoided. The peak of the bensoic acid on this column is sharp and symmetric without tailing. Diethyl phthalate is used as internal standard and the amout of benzoic acid in beverage is determined. The analysis results show the average recovery is 99 7% and the relative standard deviation is 1 2%.