NO2+化学电离质谱法检测烷烃类挥发性有机物OA

Volatile organic compounds(VOCs)are significant components of atmospheric pollution.Among them,alkane compounds,due to their relatively stable chemical properties,pose challeng-es such as low sensitivity and poor selectivity in conventional detection methods.In this study,NO2+chemical ionization mass spectrometry(CI(NO2+)-MS)was employed for the detection and analysis of alkane VOCs.Experimental results demonstrate that the CI(NO2+)-MS method exhibits excellent de-tection performance for C5-C11 alkanes.Within the concentration range of 10-500 nL/L,a strong linear relationship was observed between the concentration and the characteristic peak height of each alkane VOC in the mass spectrum,with correlation coefficients all greater than 0.99.The detection limits ranged from 3.41 to 9.91 nL/L.The spiked recovery rates for samples were between 90.1%and 105%,and the relative standard deviation of the measurement results was 2.1%-4.4%(n=5).This method provides a new technique for real-time monitoring of alkane VOCs in the atmosphere.It is important for controlling pollution from petrochemical plants and for advancing atmospheric chemis-try research.