气相色谱法同步测定牙膏管中3种残留溶剂的含量

Simultaneous determination of three residual solvents in toothpaste tube by gas chromatography

建立了气相色谱法测定牙膏管中3种溶剂残留量的分析方法。以N,N-二甲基甲酰胺溶液为萃取溶剂,在超声条件下萃取牙膏管中的甲醇、乙酸乙酯和甲苯,萃取液经PEG-20M(30 m×0.32 mm×0.5μm)毛细管色谱柱分离利用氢焰离子化检测器(FID检测器)进行测定。在流量1.5 mL/min,分流比35∶1,FID检测器温度300℃条件下,甲醇、乙酸乙酯和甲苯可以得到良好地分离,峰型较好。方法线性相关性均大于0.999;精密度RSD(n=6)为1.3%、2.5%、1.6%,回收率为90.5%～108.3%;检出限分别为0.2,0.2,0.003 mg/m^2。

A method for quantitatively determining the residual solvents in toothpaste tube by gas chromatography was established.Three residual solvents including methanol,ethyl acetate and toluene were extracted from toothpaste tube under ultrasonication using N,N-dimethylformamide as extracting agent.The obtained extract was separated via capillary column PEG-20M(30 m×0.32 mm×0.5μm),and detected by hydrogen flame ionization detector(FID).The three residual solvents in the toothpaste tube were well separated with highquality peak patterns in the condition of flow rate of 1.5 mL/min and split ratio of 35∶1 and FID detector temperature of 300°C.The correlation coefficients(R^2)for the linear fittings are all higher than 0.999.The relative standard deviations(RSD)(n=6)for detection of methanol,ethyl acetate and toluene are 1.3%,2.5%and 1.6%,respectively.The recoveries are in the range of 90.5%~108.3%.Furthermore,the detection limits of methanol,ethyl acetate and toluene are 0.2 mg/m^2,0.2 mg/m^2 and 0.003 mg/m^2 respectively.