毛细管气相色谱法检测2,4-二甲基苯胺及其异构体

Capillary Gas Chromatography for Determining of 2,4-Xylidine and Its Isomers

提出2,4-二甲基苯胺及其异构体2,6-二甲基苯胺、3,5-二甲基苯胺、2,3-二甲基苯胺的毛细管柱气相色谱分离检测方法,并对2,4-二甲基苯胺的含量进行分析.样品用甲醇稀释,采用HP-INNOWax Polyethylene Glycol毛细管柱程序升温进行分离,经FID检测器测定,用外标法计算含量.在5 mg.mL-1-30 mg.mL-1浓度范围内2,4-二甲基苯胺线性良好,r=0.99989.精密度试验2,4-二甲基苯胺RSD=0.62%.相当于对照品溶液浓度的80%、100%、120%的溶液的平均回收率分别为100.6%(RSD=1.92%)、100.0%(RSD=1.12%)、100.3%(RSD=0.97%).该方法选择性强,灵敏度高,重现性好,测试准确快速.

The paper establishes the method of capillary gas chromatography for separating 2,4-xylidine and its isomer such as 2,6-xylidine, 3,5-xylidine, 2,3-xylidine, and analyzes content of 2,4-xylidine.Samples are diluted with methanol. GC is determined with FID detection and HP-INNOWax Polyethylene Glycol capillary column are used for the temperature program ramps. Content are calculated with external standard method. The calibration curve is linear （r=0.99989） within the range of 5 mg·mL^-130 mg·mL^-1 for 2,4-xylidine. Precision test 2,4-xylidine RSD--0.62%. 80% level＇s average recovery rate is 100,6%（ RSD=1.92%, n=3）, 100% level＇s average recovery rate is 100.0%（ RSD=1.12%, n=3）, 120% level＇s average recovery rate is 100.3%（ RSD=0.97%, n=3）.This method is simple, quick, and accurate and the assay result is suitable for the quality control of 2,4-xylidine.