卷烟中保湿剂的气相色谱测定法

Determination of humectants in cigarettes by gas chromatography

目的建立卷烟中保湿剂（丙二醇、甘油及三甘醇）的气相色谱测定方法。方法卷烟样品在温度（22±1）℃、湿度（60±3）％条件下平衡12h后称重，用含有2mg／ml1，3-丁二醇内标的甲醇溶液振荡提取1h并过滤后进样，经气相色谱分离后，火焰离子化检测器检测，以保留时间定性，以内标法定量。结果该方法对丙二醇、甘油、三甘醇的检出限分别为0．0009、0．0020、0．0021mg／ml，测定下限分别为0．0036、0.0080、0．0084mg/ml，按照4g烟草样品计算测定范围分别为0．04—10．21、0．10～40．18、0．10～10．18mg／g。对不同浓度的实际样品测定的日间精密度（以相对标准偏差表示）范围为1．76％～7．05％，高、中、低浓度加标回收率范围为96．7％-110．3％。结论该方法前处理过程简单快捷，测定灵敏、准确，适用于卷烟中保湿剂的测定。

Objective To establish a method for the determination of humectants （propylene glycol, glycerol and triethylene glycol） in cigarettes by gas chromatography. Methods The cigarette samples were weighed after conditioning at a temperature of （22±1）℃ and humidity of （60±3）% for 12 h, and then extracted by methanol solution containing 2 mg/ml 1, 3-butanediol （internal standard） on a shaker for 1 h. The extracting solution was fihed by PTFE filter and then the target compounds were separated by gas chromatography and detected by flame ionization detector （FID）. The target compounds were qualitatively determined by retention time and quantitatively determined by internal standard methods. Results The limits of detection of propylene glycol, glycerol and triethylene glycol were 0.000 9, 0.002 0, 0.002 1 mg/ml and the limits of quantification were 0.003 6, 0.008 0, 0.008 4 mg/ml, as well as the linear ranges were 0.04-10.21, 0.10-40.18, 0.10-10.18 mg/g with 4 g tobacco samples respectively. The day to day precisions （relative standard deviation） were 1.76%-7.05%, and the recovery rates were 96.7%-110.3% in determining different level of samples. Conclusion The method is sensitive, accurate and convenient with simple and quick pre-processing procedure. It can be used in the determination of humectants in cigarettes.