便携式气相色谱-质谱法测定工作场所空气中2-甲基丙醛、2-甲基丁醛和3-甲基丁醛

Detection of 2-methylpropanal,2-methyl butanal and 3-methyl butanal in workplace air by portable gas chromatography-mass spectrometry

目的建立便携式气相色谱-质谱(GC-MS)法测定工作场所空气中2-甲基丙醛、2-甲基丁醛和3-甲基丁醛的方法。方法利用便携式GC-MS仪取样探头直接采集工作场所空气,经Tri-bed吸附管富集后,热解吸进样分析,采用保留时间和特征离子定性,特征离子峰面积定量。结果本方法检测2-甲基丙醛、2-甲基丁醛、3-甲基丁醛的线性范围分别为0.079~15.880、0.080~16.080、0.160~32.120 mg/m^3,相关系数均大于0.999,检出限分别为0.012、0.007、0.013 mg/m^3,定量下限分别为0.041、0.023、0.044 mg/m^3,加标回收率为92.2%~104.4%,批内相对标准偏差(RSD)为5.8%~9.1%,批间RSD为9.3%~19.6%。结论本方法准确度和精密度较高,适用于工作场所空气中2-甲基丙醛、2-甲基丁醛、3-甲基丁醛的快速定性和定量检测。

Objective To establish a method for detection of 2-methylpropanal,2-methyl butanal and 3-methyl butanal in workplace air by portable gas chromatography-mass spectrometry( GC-MS). Methods The workplace air was collected by portable GC-MS sampling probe. After enrichment by Tri-bed tube,the thermal desorption sample was analyzed by retention time and characteristic ion characterization. The characteristic ion peak area was quantified. Results The linear ranges of 2-methylpropanal,2-methyl butanal and 3-methyl butanal were 0. 079-15. 880,0. 080-16. 080 and 0. 161-32. 120 mg/m^3,respectively. All the correlation coefficients were greater than 0. 999. The detection limits were 0. 012,0. 007 and0. 013 mg/m^3,and the quantitation limits were 0. 041,0. 023 and 0. 044 mg/m^3,respectively. The recovery rates of2-methylpropanal,2-methyl butanal and 3-methyl butanal were 92. 2%-104. 4%. The within-run relative standard deviation( RSD) was 5. 8%-9. 1%. The between-run RSD of different batches samples was 9. 3%-19. 6%. Conclusion This method has high accuracy and is precise,which is suitable for rapid qualitative and quantitative detection of2-methylpropanal,2-methyl butanal and 3-methyl butanal in workplace air.