Nishikido Yuto, Sekimoto Kanako
Graduate School of Nanobioscience, Yokohama City University, 22-2 Seto, Kanazawa-ku, Yokohama, Kanagawa 236-0027, Japan.
Mass Spectrom (Tokyo). 2023;12(1):A0127. doi: 10.5702/massspectrometry.A0127. Epub 2023 Jul 29.
The ionization and fragmentation patterns of 24 compounds with elemental composition of CHO, including isomeric esters and alkanoic acids, were investigated by atmospheric pressure corona discharge ionization collision-induced dissociation (CID) mass spectrometry in the positive-ion mode. All compounds were ionized as protonated molecules and NH adducts. In addition, fragment ions were observed in mass spectra of esters other than methyl esters, which are owing to the dissociation of the alkyl group in the alcohol side from the protonated molecules. In CID spectra, protonated alkanoic acids/methyl esters split off HO/CHOH and CO or the alkyl group in the acid side, depending on the carbon chain length. Protonated esters (other than methyl esters) mainly fragmented the alkyl group in the alcohol side. These general rules on ionization and fragmentation patterns can provide relevant information on the discrimination of isomers.
采用大气压电晕放电电离碰撞诱导解离（CID）质谱正离子模式，研究了24种CHO元素组成的化合物的电离和碎裂模式，包括异构酯和链烷酸。所有化合物均以质子化分子和NH加合物形式电离。此外，在甲酯以外的酯类质谱中观察到碎片离子，这是由于质子化分子中醇侧烷基的解离。在CID光谱中，质子化链烷酸/甲酯根据碳链长度分裂出HO/CHOH和CO或酸侧的烷基。质子化酯（甲酯除外）主要使醇侧的烷基碎裂。这些关于电离和碎裂模式的一般规则可为异构体的鉴别提供相关信息。
