单壁碳纳米管固相萃取-气相色谱-质谱联用法测定茶油中6种邻苯二甲酸酯

建立了单壁碳纳米管（SWCNTs）为吸附剂的固相萃取净化-气相色谱-质谱检测茶油中6种邻苯二甲酸酯（PAEs）的分析方法。样品经正己烷稀释，玻璃SWCNTs SPE小柱净化，GC-MS选择离子监测（SIM）模式测定，外标法定量。对正己烷的稀释体积、吸附材料的类型、SWCNTs用量、淋洗液用量、洗脱溶剂类型和体积等影响萃取效率的条件进行了优化，得到的最优萃取条件为：正己烷稀释体积为5 mL，SWCNTs用量为0.6 g，淋洗液为20 mL正己烷，洗脱溶剂为5 mL甲苯。6种PAEs在0.05~1.0 mg/L范围内线性关系良好，相关系数（r）均大于0.9999；在0.05~1.0 mg/kg添加范围内，6种目标物的平均回收率为86.4%~111.7%，相对标准偏差为4.2%~10.4%。该方法准确、快速，可满足茶油中6种邻苯二甲酸酯的检测需要。

Determination of six phthalate acid esters in camellia oil by gas chromatography-mass spectrometry coupled with solid-phase extraction using single-walled carbon nanotubes as adsorbent

An analytical method based on solid-phase extraction with single-walled carbon nanotubes (SWCNTs) as adsorbent was developed for the simultaneous determination of six phthalate acid esters (PAEs) in camellia oil by gas chromatography-mass spectrometry (GC-MS). The samples were diluted by hexane and then cleaned up with a glass SWCNTs solid phase extraction (SPE) column. The PAEs were measured by GC-MS in selected ion monitoring (SIM) mode, using external standard method for quantitative analysis. The important factors affecting extraction efficiency, such as the dilution volume of hexane, the type of adsorbent material, the dosage of SWCNTs, the volume of wash solution, the type and volume of elution solution were optimized. The optimal conditions were as follows: the dilution volume of hexane was 5 mL, the dosage of SWCNTs was 0.6 g, the wash solution was 20 mL hexane, and the elution solution was 5 mL toluene. The six PAEs had a good linear range from 0.05 mg/L to 1.0 mg/L, with the correlation coefficients (r) all above 0.9999. The average recoveries of the six targets in spiked camellia oil (from 0.05 mg/kg to 1.0 mg/kg) ranged from 86.4% to 111.7% with the relative standard deviations (RSDs) from 4.2% to 10.4%. The developed method is accurate, quick and suitable for the determination of the six PAEs in camellia oil.