title: Coupling corona discharge for ambient extractive ionization mass spectrometry.
abstract: Unlike the extractive electrospray ionization (EESI) technique described elsewhere, a corona discharge instead of electrospray ionization has been utilized to charge a neutral solvent spray under ambient conditions for the generation of highly charged microdroplets, which impact a neutral sample plume for the extractive ionization of the analytes in raw samples without any sample pretreatment. Using the positive ion mode, molecular radical cations were easily generated for the detection of non-polar compounds (e.g., benzene, cyclohexane, etc.), while protonated molecular ions of polar compounds (e.g., acetonitrile, acetic ether) were readily produced for the detection. By dispensing the matrix in a relatively large space, this method tolerates highly complex matrices. For a given sample such as lily fragrances, more compounds were detected by the method established here than the EESI technique. An acceptable relative standard deviation (RSD 8.9%, n = 11) was obtained for the direct measurement of explosives (10 ppb) in waste water samples. The experimental data demonstrate that this method could simultaneously detect both polar and non-polar analytes with high sensitivity, showing promising applications for the rapid detection of a wide variety of compounds present in complex matrices.
authors.affiliation: Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation, College of Chemistry, Biology and Material Sciences, East China Institute of Technology, Nanchang, Jiangxi Province 330013, P. R. China.
authors.forename: Bin
authors.initials: B
authors.lastname: Hu
authors.forename: Xinglei
authors.initials: X
authors.lastname: Zhang
authors.forename: Ming
authors.initials: M
authors.lastname: Li
authors.forename: Xuejiao
authors.initials: X
authors.lastname: Peng
authors.forename: Jing
authors.initials: J
authors.lastname: Han
authors.forename: Shuiping
authors.initials: S
authors.lastname: Yang
authors.forename: Yongzhong
authors.initials: Y
authors.lastname: Ouyang
authors.forename: Huanwen
authors.initials: H
authors.lastname: Chen