{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,9]],"date-time":"2026-10-09T05:26:33Z","timestamp":1791523593909,"version":"4.3.4"},"reference-count":29,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2023,9,13]],"date-time":"2023-09-13T00:00:00Z","timestamp":1694563200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the National Key Research and Development Program of China","award":["2022YFC3700203"],"award-info":[{"award-number":["2022YFC3700203"]}]},{"name":"the National Key Research and Development Program of China","award":["tsqn201909039"],"award-info":[{"award-number":["tsqn201909039"]}]},{"name":"the National Key Research and Development Program of China","award":["2021GXRC058"],"award-info":[{"award-number":["2021GXRC058"]}]},{"name":"Young Taishan Scholars","award":["2022YFC3700203"],"award-info":[{"award-number":["2022YFC3700203"]}]},{"name":"Young Taishan Scholars","award":["tsqn201909039"],"award-info":[{"award-number":["tsqn201909039"]}]},{"name":"Young Taishan Scholars","award":["2021GXRC058"],"award-info":[{"award-number":["2021GXRC058"]}]},{"name":"College 20 Project from Ji Nan Science &amp; Technology Bureau","award":["2022YFC3700203"],"award-info":[{"award-number":["2022YFC3700203"]}]},{"name":"College 20 Project from Ji Nan Science &amp; Technology Bureau","award":["tsqn201909039"],"award-info":[{"award-number":["tsqn201909039"]}]},{"name":"College 20 Project from Ji Nan Science &amp; Technology Bureau","award":["2021GXRC058"],"award-info":[{"award-number":["2021GXRC058"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Single photon ionization (SPI) based on vacuum ultraviolet (VUV) lamps has been extensively investigated and applied due to its clean mass spectra as a soft ionization method. However, the photon energy of 10.6 eV and photon flux of 1011 photons s\u22121 of a commercial VUV lamp limits its range of ionizable analytes as well as its sensitivity. This work designs a chemical ionization focusing integrated (CIFI) ionization source time-of-flight mass spectrometry (TOFMS) based on a VUV lamp for the detection of volatile organic compounds (VOCs) and oxygenated volatile organic compounds (OVOCs). The photoelectrons obtained from the VUV lamp via the photoelectric effect ionized the oxygen and water in the air to obtain the reagent ions. The ion\u2013molecule-reaction region (IMR) is constituted by a segmented quadrupole that radially focuses the ions using a radio-frequency electric field. This significantly enhances the yield and transport efficiency of the product ions leading to a great improvement in sensitivity. As a result, a 44-fold and 1154-fold increase in the signal response for benzene and pentanal were achieved, respectively. To verify the reliability of the ionization source, the linear correspondence and repeatability of benzene and pentanal were investigated. Satisfactory dynamic linearity was obtained in the mixing ratio range of 5\u201350 ppbv, and the relative standard deviation (RSD) of inter-day reached 3.91% and 6.26%, respectively. Finally, the CIFI\u2212TOFMS was applied to the determination of OVOCs, and the LOD of 12 types of OVOCs reached the pptv level, indicating that the ionization source has the potential for accurate and sensitive online monitoring of atmospheric OVOCs.<\/jats:p>","DOI":"10.3390\/molecules28186600","type":"journal-article","created":{"date-parts":[[2023,9,14]],"date-time":"2023-09-14T10:09:22Z","timestamp":1694686162000},"page":"6600","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Development and Application of a Chemical Ionization Focusing Integrated Ionization Source TOFMS for Online Detection of OVOCs in the Atmosphere"],"prefix":"10.3390","volume":"28","author":[{"given":"Ruidong","family":"Liu","sequence":"first","affiliation":[{"name":"Environment Research Institute, Shandong University, Qingdao 266237, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yingzhe","family":"Guo","sequence":"additional","affiliation":[{"name":"Environment Research Institute, Shandong University, Qingdao 266237, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mei","family":"Li","sequence":"additional","affiliation":[{"name":"Environment Research Institute, Shandong University, Qingdao 266237, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jing","family":"Li","sequence":"additional","affiliation":[{"name":"Environment Research Institute, Shandong University, Qingdao 266237, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dong","family":"Yang","sequence":"additional","affiliation":[{"name":"Environment Research Institute, Shandong University, Qingdao 266237, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Keyong","family":"Hou","sequence":"additional","affiliation":[{"name":"Environment Research Institute, Shandong University, Qingdao 266237, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,9,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/0168-1176(90)85063-8","article-title":"Some Reflections on the Early Days of Mass Spectrometry at the University of Minnesota","volume":"100","author":"Nier","year":"1990","journal-title":"Int. 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