Jeong, Eun Sook Cha, Eunju Cha, Sangwon Kim, Sunghwan Bin Oh, Han Kwon, Oh-Seung Lee, Jaeick 2024-01-20T00:04:27Z 2024-01-20T00:04:27Z 2021-09-03 2017-11 0003-2700 https://pubs.kist.re.kr/handle/201004/122126 In this study, a hydrogen/deuterium (H/D) exchange method using gas chromatography-electrospray ionization/mass spectrometry (GC-ESI/MS) was first investigated as a novel tool for online H/D exchange of multitarget analytes. The GC and ESI source were combined with a homemade heated column transfer line. GC-ESI/MS-based H/D exchange occurs in an atmospheric pressure ion source as a result of reacting the gas-phase analyte eluted from GC with charged droplets of deuterium oxide infused as the ESI spray solvent. The consumption of the deuterated solvent at a flow rate of 2 mu L min(-1) was more economical than that in online H/D exchange methods reported to date. In-ESI-source H/D exchange by GC-ESI/MS was applied to 11 stimulants with secondary amino or hydroxyl groups. After H/D exchange, the spectra of the stimulants showed unexchanged, partially exchanged, and fully exchanged ions showing various degrees of exchange. The relative abundances corrected for naturally occurring isotopes of the fully exchanged ions of stimulants, except for etamivan, were in the range 24.3-85.5%. Methylephedrine and cyclazodone showed low H/D exchange efficiency under acidic, neutral, and basic spray solvent conditions and nonexchange for etamivan with an acidic phenolic OH group. The in-ESI-source H/D exchange efficiency by GC-ESI/MS was sufficient to determine the number of hydrogen by elucidation of fragmentation from the spectrum. Therefore, this online H/D exchange technique using GC-ESI/MS has potential as an alternative method for simultaneous H/D exchange of multitarget analytes. English AMER CHEMICAL SOC Online Simultaneous Hydrogen/Deuterium Exchange of Multitarget Gas-Phase Molecules by Electrospray Ionization Mass Spectrometry Coupled with Gas Chromatography Article 10.1021/acs.analchem.7b03218 1 ANALYTICAL CHEMISTRY, v.89, no.22, pp.12284 - 12292 ANALYTICAL CHEMISTRY 89 22 12284 12292 N scie scopus 000416498100055 2-s2.0-85034964980 Chemistry, Analytical Chemistry Article HYDROGEN-DEUTERIUM EXCHANGE ATMOSPHERIC-PRESSURE STRUCTURAL ELUCIDATION H/D EXCHANGE LC-MS ANABOLIC-STEROIDS METABOLITES COMBINATION IMPURITIES SPECIATION