固相微萃取-气相色谱串联两级质谱法测定水中10种藻类代谢产物

文中建立了固相微萃取-气相色谱串联两级质谱法测定地表水中的10种藻类代谢产物的含量，研究了萃取时间、萃取温度、萃取剂量、萃取纤维等预处理参数对嗅味物质含量的影响，同时对不同规格的色谱柱进行分离效果比较。结果表明，在萃取时间为25 min、萃取温度为65℃、氯化钠含量为1.7 g的测定条件下，采用50/30μm DVB/CAR/PDMS萃取头进行预处理，HP-5MS色谱柱进行分离，质谱检测器进行测定，可以使检测结果达到最优效果。方法的质量浓度均达到5.00～100.00 ng/L,工作曲线回归方程的相关系数R²>0.995;方法检出限(2S/N)为0.14～1.00 ng/L。在纯水加标量为20.00、50.00、80.00 ng/L时，平均回收率为92.0%～109.0%,精密度RSD为0.4%～8.9%,实际水样加标的平均回收率为83.9%～101.8%。该方法检测浓度数量级在纳克级，灵敏度较固相萃取-气相色谱-质谱法提高1 000倍，更适合地表水和饮用水中低浓度藻类代谢产物的检测要求。

Determination of 10 Algae Metabolites in Water by Solid Phase Microextraction (SPME) and Gas Chromatography Tandem Two-Stage Mass Spectrometry (GC-MS)

A solid phase microextraction(SPME)-gas chromatography tandem two-stage mass spectrometry(GC-MS)was established for the determination of 10 algae metabolites in surface water.Effects of extraction time,extraction temperature,extraction dose,extraction fiber and other pretreatment parameters on the content of odor substances were studied.Meanwhile,the separation effects of different sizes of chromatographic columns were compared.Results showed that while extraction time was 25 min,extraction temperature was 65℃and the content of sodium chloride was 1.7 g,water samples were pretreated by 50/30μm DVB/CAR/PDMS extraction head,separated by HP-5MS chromatographic columns and determined by mass spectrometry,which could achieve the optimal effect.Concentrations of methods are 5.00~100.00 ng/L,and correlation coefficient(R²)of regression equation of working curve was>0.995.Detection limit(2S/N)was 0.14~1.00 ng/L.When pure water was added with scalars of 20.00,50.00 ng/L and 80.00 ng/L,average recovery was 92.0%~109.0%,precision RSD was 0.4%~8.9%,and the average recovery of actual water sample was 83.9%~101.8%.Sensitivity of this method is 1000 times higher than that of SPE-GC-MS.It is more suitable for detecting low concentration algal metabolites in surface water and drinking water.