HS-SPME–GC–MS法测定水中2-甲基异冰片及土臭素

采用顶空固相微萃取–气质联用(HS-SPME–GC–MS)的方法对地表水中2-甲基异冰片(2-MIB)和土臭素(GSM)进行分析测定。通过试验确定了HS-SPME的最佳萃取条件:萃取头为DVB/CAR/PDMS,萃取时间为30 min,萃取温度为70℃,NaCl的加入量为30%(质量分数),萃取纤维在GC上的解吸温度为250℃。用内标法进行定量,2-MIB,GSM的质量浓度在5~100 ng/L范围内与色谱峰面积呈良好的线性关系,线性相关系数(r2)分别为0.999 7,0.997 0,检出限分别为0.8,1.7 ng/L。采用该法对水样进行测定,2-MIB,GSM测定结果的相对标准偏差为2.6%~6.3%(n=6),加标回收率为92%~112%。该方法能简单、快速地测定水中痕量嗅味物质。

Determination of 2-Methylisoborneol and Geosmin in Water by HS-SPME-GC-MS

Headspace solid-phase microextraction-gas chromatography-mass spectrometry （HS-SPME-GC-MS） was used to detect the trace 2-MIB, GSM in surface water. The optimal operation conditions of SPME were obtained as follows：extraction time 30 min, extraction temperature 70℃, NaCl 30%（mass fraction）,desorption temperature 250℃in GC. Internal standard method was used to quantify, concentration of 2-MIB, GSM was linear with peak area in the range of 5-100 ng/L with the correlation coefficient （r2） of 0.999 5, 0.999 6, respectively. The detection limits of 2-MIB, GSM were 0.8, 1.7 ng/L, respectively. The method was used to detect water samples, the relative standard deviations of 2-MIB, GSM were 2.6%-6.3%（n=6）, and the recoveries were 92%-112%. The method is simple and fast for the determination of trace odor compounds in water.