{"title":"VUV照明生成C2H5O+并掺杂丙醛增强检测气相甲醛。","authors":"Zhiyang Wei, , , Lixin Shan, , , Yongze Gao, , , Zhiyuan Luo, , , Shiyu Cheng, , and , Jinian Shu*, ","doi":"10.1021/jasms.5c00181","DOIUrl":null,"url":null,"abstract":"<p >Formaldehyde (CH<sub>2</sub>O) is one of the main indoor organic pollutants due to its carcinogenicity and teratogenicity. However, CH<sub>2</sub>O has been an undetectable species for common VUV lamp-based photoionization mass spectrometry (PI-MS) due to its high ionization energy. In this article, we report a mass spectrometric technique developed for detecting gas-phase CH<sub>2</sub>O by monitoring C<sub>2</sub>H<sub>5</sub>O<sup>+</sup> (<i>m</i>/<i>z</i> 45) formed in VUV illumination and enhanced by doping propionaldehyde. The unique mass peak at <i>m</i>/<i>z</i> 45 was observed by VUV illuminating ppm-level CH<sub>2</sub>O in ∼1300 Pa of nitrogen or synthetic air. The <i>m</i>/<i>z</i> 45 ion was assigned to be C<sub>2</sub>H<sub>5</sub>O<sup>+</sup> via verification with a high-resolution mass spectrometric measurement and a deuteron transfer experiment. The formation process of the C<sub>2</sub>H<sub>5</sub>O<sup>+</sup> ion observed in the experiment is similar to that of C<sub>2</sub>H<sub>5</sub>O<sup>+</sup> formed in the combustion of hydrocarbons, discussed in the paper. Doping propionaldehyde in the carrier gas remarkably enhanced the signal intensity of C<sub>2</sub>H<sub>5</sub>O<sup>+</sup> by nearly 13 times. The detection sensitivities of CH<sub>2</sub>O via C<sub>2</sub>H<sub>5</sub>O<sup>+</sup> reached 46.0 counts ppb<sup>–1</sup>, and the LOD of the method was 4.3 ppb, enhanced by doping propionaldehyde. The influence of the humidity on the detection could be alleviated with desiccants, and the recovery with CaCl<sub>2</sub>·2H<sub>2</sub>O as the desiccant was achieved at 30% of the dry condition under 100% RH. This experiment demonstrated that the <i>m</i>/<i>z</i> 45 ions can be used as the characteristic ion for detecting CH<sub>2</sub>O.</p>","PeriodicalId":672,"journal":{"name":"Journal of the American Society for Mass Spectrometry","volume":"36 10","pages":"2181–2188"},"PeriodicalIF":2.7000,"publicationDate":"2025-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Detection of Gas-Phase Formaldehyde via C2H5O+ Produced by VUV Illumination and Enhanced by Doping Propionaldehyde\",\"authors\":\"Zhiyang Wei, , , Lixin Shan, , , Yongze Gao, , , Zhiyuan Luo, , , Shiyu Cheng, , and , Jinian Shu*, \",\"doi\":\"10.1021/jasms.5c00181\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p >Formaldehyde (CH<sub>2</sub>O) is one of the main indoor organic pollutants due to its carcinogenicity and teratogenicity. However, CH<sub>2</sub>O has been an undetectable species for common VUV lamp-based photoionization mass spectrometry (PI-MS) due to its high ionization energy. In this article, we report a mass spectrometric technique developed for detecting gas-phase CH<sub>2</sub>O by monitoring C<sub>2</sub>H<sub>5</sub>O<sup>+</sup> (<i>m</i>/<i>z</i> 45) formed in VUV illumination and enhanced by doping propionaldehyde. The unique mass peak at <i>m</i>/<i>z</i> 45 was observed by VUV illuminating ppm-level CH<sub>2</sub>O in ∼1300 Pa of nitrogen or synthetic air. The <i>m</i>/<i>z</i> 45 ion was assigned to be C<sub>2</sub>H<sub>5</sub>O<sup>+</sup> via verification with a high-resolution mass spectrometric measurement and a deuteron transfer experiment. The formation process of the C<sub>2</sub>H<sub>5</sub>O<sup>+</sup> ion observed in the experiment is similar to that of C<sub>2</sub>H<sub>5</sub>O<sup>+</sup> formed in the combustion of hydrocarbons, discussed in the paper. Doping propionaldehyde in the carrier gas remarkably enhanced the signal intensity of C<sub>2</sub>H<sub>5</sub>O<sup>+</sup> by nearly 13 times. The detection sensitivities of CH<sub>2</sub>O via C<sub>2</sub>H<sub>5</sub>O<sup>+</sup> reached 46.0 counts ppb<sup>–1</sup>, and the LOD of the method was 4.3 ppb, enhanced by doping propionaldehyde. The influence of the humidity on the detection could be alleviated with desiccants, and the recovery with CaCl<sub>2</sub>·2H<sub>2</sub>O as the desiccant was achieved at 30% of the dry condition under 100% RH. This experiment demonstrated that the <i>m</i>/<i>z</i> 45 ions can be used as the characteristic ion for detecting CH<sub>2</sub>O.</p>\",\"PeriodicalId\":672,\"journal\":{\"name\":\"Journal of the American Society for Mass Spectrometry\",\"volume\":\"36 10\",\"pages\":\"2181–2188\"},\"PeriodicalIF\":2.7000,\"publicationDate\":\"2025-09-15\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of the American Society for Mass Spectrometry\",\"FirstCategoryId\":\"92\",\"ListUrlMain\":\"https://pubs.acs.org/doi/10.1021/jasms.5c00181\",\"RegionNum\":2,\"RegionCategory\":\"化学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"BIOCHEMICAL RESEARCH METHODS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of the American Society for Mass Spectrometry","FirstCategoryId":"92","ListUrlMain":"https://pubs.acs.org/doi/10.1021/jasms.5c00181","RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"BIOCHEMICAL RESEARCH METHODS","Score":null,"Total":0}
Detection of Gas-Phase Formaldehyde via C2H5O+ Produced by VUV Illumination and Enhanced by Doping Propionaldehyde
Formaldehyde (CH2O) is one of the main indoor organic pollutants due to its carcinogenicity and teratogenicity. However, CH2O has been an undetectable species for common VUV lamp-based photoionization mass spectrometry (PI-MS) due to its high ionization energy. In this article, we report a mass spectrometric technique developed for detecting gas-phase CH2O by monitoring C2H5O+ (m/z 45) formed in VUV illumination and enhanced by doping propionaldehyde. The unique mass peak at m/z 45 was observed by VUV illuminating ppm-level CH2O in ∼1300 Pa of nitrogen or synthetic air. The m/z 45 ion was assigned to be C2H5O+ via verification with a high-resolution mass spectrometric measurement and a deuteron transfer experiment. The formation process of the C2H5O+ ion observed in the experiment is similar to that of C2H5O+ formed in the combustion of hydrocarbons, discussed in the paper. Doping propionaldehyde in the carrier gas remarkably enhanced the signal intensity of C2H5O+ by nearly 13 times. The detection sensitivities of CH2O via C2H5O+ reached 46.0 counts ppb–1, and the LOD of the method was 4.3 ppb, enhanced by doping propionaldehyde. The influence of the humidity on the detection could be alleviated with desiccants, and the recovery with CaCl2·2H2O as the desiccant was achieved at 30% of the dry condition under 100% RH. This experiment demonstrated that the m/z 45 ions can be used as the characteristic ion for detecting CH2O.
期刊介绍:
The Journal of the American Society for Mass Spectrometry presents research papers covering all aspects of mass spectrometry, incorporating coverage of fields of scientific inquiry in which mass spectrometry can play a role.
Comprehensive in scope, the journal publishes papers on both fundamentals and applications of mass spectrometry. Fundamental subjects include instrumentation principles, design, and demonstration, structures and chemical properties of gas-phase ions, studies of thermodynamic properties, ion spectroscopy, chemical kinetics, mechanisms of ionization, theories of ion fragmentation, cluster ions, and potential energy surfaces. In addition to full papers, the journal offers Communications, Application Notes, and Accounts and Perspectives