气相色谱法测定邻苯二甲酸酯结果的影响因素

Effect factors on Determination of Phthalate Esters by Gas Chromatography

以邻苯二甲酸二丁酯和邻苯二甲酸二(2-乙基己基)酯为例,考察了进样体积、分流比及溶剂极性效应等因素对气相色谱法测定结果的影响。结果表明溶剂效应对测定结果影响最为显著。当用甲醇作溶剂时,目标化合物的响应值偏小,峰形不对称,且进样重复性差,对定量结果影响较大。在气相色谱测定中宜选用极性比甲醇弱的其它溶剂作为样品溶液介质或标准溶液稀释溶剂,如乙酸乙酯、丙酮、二氯甲烷等,以提高样品测定的精密度和准确度。

Dibutyl phthalate （DBP） and bis（2-ethylhexyl） phthalate （DEHP） were taken as examples to discuss theeffect factors on the determination results by gas chromatography. The test results showed that the most influential effectto the detection was the solvent effect. When methanol was used as solvent,small responses of target compounds,unsymmetrypeak and bad repeatability appeared,so the effect on quantitation was significant. It was suggested that some solventssuch as methylene chloride,acetone,ethyl acetate and so on,whose polarity was smaller than methanol,should be selectedas the medium or the dilution solvent of standard solution and sample solution,so that the stability and accuracy of quantitationcould be assured.