应用搅拌棒吸附萃取富集及热解吸进样与气相色谱-质谱相结合测定了水样中3种烷基酚(即正辛基酚、叔辛基酚和正壬基酚)的含量。将水样预先用盐酸调节其酸度至pH 3,分取10.00 mL置于顶空瓶中,放入搅拌棒进行吸附萃取。取出搅拌棒,置于热脱附管上解吸并通过程序升温进样系统进样,用DB-5MS柱进行色谱分离。质谱分析条件:电子轰击正离子源,全扫描模式(定性分析)和选择离子扫描模式(定量分析)。3种烷基酚的质量浓度均在5~200 ng·L-1范围内与其峰面积呈线性关系,方法的检出限(3S/N)在1.2~2.5 ng·L-1之间。以实际水样为基体进行加标回收试验,测得回收率在95.0%~118%之间,测定值的相对标准偏差(n=5)在0.90%~10%之间。

GC-MS was applied to the determination of 3 alkylphenols, i.e. n-octylphenol, t-octylphenol and n-nonylphenol in water with stirring rod adsorptive extraction and thermal desorption. The water sample was adjusted to pH 3.0 with HCl, an aliquot of 10.00 mL was transferred into the head-space flask and extracted with stirring rod adsorption. The stirring rod was removed out and put on the thermal desorption tube and the desorbed analytes were introduced into the instrument by the CIS4 sampling system and separated on DB-5MS column. MS determination was carried out under full-scanning mode (for qualitative analysis) and selected ion monitoring mode (for quantitative analysis). Linear relationships between values of peak area and mass concentration of 3 alkylphenols were kept in the same range of 5-200 ng·L-1, with detection limits (3S/N) in the range of 1.2-2.5 ng·L-1. Recovery was tested by standard addition method using substantial water samples as matrixes, giving values of recovery and RSD′s (n=5) in the ranges of 95.0%-118% and 0.90%-10% respectively.