提出了测定聚对苯二甲酸乙二醇酯(PEGTP)瓶装纯水中乙醛迁移量的气相色谱-质谱法。水样(100 mL)中乙醛用2,4-二硝基苯肼在pH 3柠檬酸盐缓冲溶液10 mL中,于40 ℃水浴上振荡1 h加热使之衍生化。冷却后用二氯甲烷萃取3次,每次10 mL。萃取液于40 ℃旋转蒸发至1.0 mL,分取1 μL进样分析。采用DB-5MS毛细管柱及在70 ℃~280 ℃范围内程序升温进行分离。线性范围在300 μg·L-1以内,检出限(3S/N)为1 μg·L-1,加入50 μg·L-1及100 μg·L-1标准溶液做回收试验及精密度试验,测得平均回收率为88%,相对标准偏差(n=5)依次为5.4%及4.5%。

GC-MS was applied to the determination of amount of acetaldehyde migrated from bottle made of polyethylene glycol terephthalate (PEGTP) into the bottled water. Acetaldehyde in water sample (100 mL) was derivatized with 2,4-dinitrophenylhydrazine in the presence of 10 mL of pH 3 citrate buffer solution, by heating at 40 ℃ on a water-bath and shaking for 1 h. After cooling, the solution was extracted thrice with 10 mL of dichloro methane each. The extracts were combined, and evaporated to 1.0 mL at 40 ℃. An aliquot of 1 μL was taken for the GC-MS analysis. DB-5MS capillary column with programmed temperature elevation (70 ℃-280 ℃) was used in GC. Linearity range was kept within 300 μg·L-1, with detection limit (3S/N) of 1 μg·L-1. Recovery and precision were tested at concentration levels of 50 μg·L-1 and 100 μg·L-1, giving value of av. recovery 88% and values of RSD′s (n=5) 5.4% and 4.5% respectively.