基于 Fe_(3)O_(4)@SiO_(2)@NH_(2)@C60的磁固相萃取/气相色谱-质谱联用检测中药材中多环芳烃

Determination of Polycyclic Aromatic Hydrocarbons in Chinese Herbal Medicines by Gas Chromatography-Mass Spectrometry with Fe_(3)O_(4)@SiO_(2)@NH_(2)@C60Magnetic Solid Phase Extraction

基于 Fe_(3)O_(4)@SiO_(2)@NH_(2)@C60磁纳米复合材料,建立了磁固相萃取/气相色谱-质谱联用同时测定中药材中16种多环芳烃(PAHs)含量的分析方法。采用傅里叶变换红外光谱仪、扫描电镜和振动样品磁力计对复合材料进行表征,证实C60改性成功;吸附性能实验结果表明, Fe_(3)O_(4)@SiO_(2)@NH_(2)@C60的吸附能力强,稳定性好,经10次重复利用后吸附效率无明显变化。考察了萃取溶剂种类、吸附剂用量、吸附时间、解吸溶剂种类以及解吸时间对中药材样品中16种PAHs萃取效率的影响。结果显示,10 mg吸附剂在4 min内即可实现对目标物的完全吸附。采用最优的磁固相萃取条件,16种PAHs在5~1 000μg/L范围内具有良好的线性关系,相关系数(r^(2))为0.994 0~0.999 9,检出限为0.2~1.2μg/kg,定量下限为0.8~3.9μg/kg,3个水平下的加标回收率为84.1%~104%,相对标准偏差(RSD)为0.70%~8.3%,日内RSD为0.20%~3.5%,日间RSD为2.2%~6.9%。所建立的方法能有效降低中药材样品中复杂基质的干扰,为中药材中PAHs含量的测定提供了一种操作简便、灵敏度高、准确性好的方法参考。

A gas chromatography-mass spectrometry with magnetic solid phase extraction based on Fe_(3)O_(4)@SiO_(2)@NH_(2)@C60magnetic nanocomposites was established for the simultaneous determination of 16 polycyclic aromatic hydrocarbons(PAHs) in Chinese herbal medicines in this paper.The composites were characterized by Fourier transform infrared spectroscopy,scanning electron microscopy and vibrating sample magnetometer to confirm the successful modification of C60.Meanwhile,adsorption experiments were conducted,which showed that the magnetic nanocomposites had a strong adsorption capacity and good stability,and the adsorption efficiency did not change significantly after10 times of reuse.The effects of extraction solvent type,sorbent dosage,adsorption time,desorption solvent type and desorption time on the extraction efficiency for 16 PAHs in herbal samples were investigated.The results showed that the complete adsorption of 10 mg of sorbent on the targets could be achieved within 4 min.Under the optimal magnetic solid phase extraction conditions,there were good linear relationships for 16 PAHs in the range of 5-1 000μg/L,with correlation coefficients(r~2) of 0.994 0-0.999 9.The limits of detection and the limits of quantitation were in the range of 0.2-1.2μg/kg and 0.8-3.9μg/kg,respectively.The spiked recoveries at three levels ranged from 84.1% to 104%,with relative standard deviations(RSDs) of 0.70%-8.3%,intra-day RSDs of 0.20%-3.5%and inter-day RSDs of 2.2%-6.9%.The developed method could effectively reduce the interference on PAHs targets from complex matrices in Chinese herbal medicine samples,and provide an easy-to-operate,sensitive and accurate method reference for the determination of PAHs in Chinese herbal medicines.