Ionization of Gas-Phase Polycyclic Aromatic Hydrocarbons in Electrospray Ionization Coupled with Gas Chromatography.
Eunju ChaEun Sook JeongSang Beom HanSangwon ChaJunghyun SonSunghwan KimHan Bin OhJaeick LeePublished in: Analytical chemistry (2018)
Herein, gas-phase polycyclic aromatic hydrocarbons (PAHs) as nonpolar compounds were ionized to protonated molecular ions [M + H]+ without radical cations and simultaneously analyzed using gas chromatography (GC)/electrospray ionization (ESI)-tandem mass spectrometry (MS/MS). The ionization profile, dissociation, and sensitivity were first investigated to understand the significant behavior of gas-phase PAHs under ESI. The formation of protonated molecular ions of PAHs was distinguished according to the analyte phase and ESI spray solvents. The protonated PAHs exhibited characteristic dissociations, such as H-loss, H2-loss, and acetylene-loss, via competition of internal energy. In addition, GC/ESI-MS/MS resulted in relatively lower concentration levels (better sensitivity) for the limits-of-detection (LODs) of PAHs than liquid chromatography (LC)/ESI-MS/MS, and it seems to result from the characteristic ionization mechanism of the gas-phase analyte under ESI. Furthermore, the LODs of gas-phase PAHs depended on molecular weight and proton affinity (PA). Consequently, we demonstrated the relationship among the analyte phases, sensitivities, and structural characteristics (molecular weight and PA) under ESI. The gas-phase PAHs provided enhanced protonation efficiency and sensitivity using GC/ESI-MS/MS, as their molecular weight and PA increased. Based on these results, we offered important information regarding the behavior of gas-phase analytes under ESI. Therefore, the present GC/ESI-MS/MS method has potential as an alternative method for simultaneous analysis of PAHs.
Keyphrases
- ms ms
- polycyclic aromatic hydrocarbons
- gas chromatography
- tandem mass spectrometry
- mass spectrometry
- liquid chromatography
- ultra high performance liquid chromatography
- high resolution mass spectrometry
- high performance liquid chromatography
- simultaneous determination
- liquid chromatography tandem mass spectrometry
- gas chromatography mass spectrometry
- solid phase extraction
- high resolution
- human health
- risk assessment
- capillary electrophoresis
- social media
- health risk assessment
- loop mediated isothermal amplification