He Jing, Zhang Hong, Liu Yaqi, Ju Yun, He Yuwei, Jiang Yanxiao, Jiang Jie
School of Marine Science and Technology, Harbin Institute of Technology (Weihai), Weihai 264209, Shandong, China.
School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150090, Heilongjiang, China.
Anal Chem. 2023 Mar 21;95(11):5018-5023. doi: 10.1021/acs.analchem.2c05472. Epub 2023 Feb 25.
Criegee intermediates (CIs) play a significant role in cell membrane peroxidation, but their identification remains elusive at the molecular level. Herein, we combined interfacial extraction and sonic spray ionization mass spectrometry to study the oxidation reaction of 1-palmitoyl-2-oleoyl--glycero-3-phospho-(1'-rac-glycerol) (POPG) mediated by ozone (O) at/near the surface of a hung water droplet. On-line interfacial extraction and ionization provided a snapshot of the short-lived CIs. Experiments in which the content of water was varied provided evidence for the formation of CIs, which has not been previously observed. Capture experiments using 5,5-dimethyl-pyrroline -oxide (DMPO) indicated that CIs could be selectively characterized, and the extracted ion current (EICs) of CIs vs DMPO-CI adducts further confirmed the successful observation of CIs. Theoretical calculation suggested that surface ozonolysis of POPG was mainly mediated by CI. These results open a new route for aqueous surface reactive species identification, and benefit toward the understanding of disease development associated with cell oxidative stress mediated by CIs.
克里吉中间体（CIs）在细胞膜过氧化过程中发挥着重要作用，但其在分子水平上的鉴定仍然难以捉摸。在此，我们结合界面萃取和超声喷雾电离质谱法，研究了臭氧（O）在悬挂水滴表面/附近介导的1-棕榈酰-2-油酰基-sn-甘油-3-磷酸-（1'-外消旋甘油）（POPG）的氧化反应。在线界面萃取和电离提供了短寿命CIs的瞬间图像。改变水含量的实验为CIs的形成提供了证据，这是以前未曾观察到的。使用5,5-二甲基-吡咯啉-N-氧化物（DMPO）的捕获实验表明，可以选择性地表征CIs，并且CIs与DMPO-CI加合物的提取离子电流（EICs）进一步证实了成功观察到CIs。理论计算表明，POPG的表面臭氧分解主要由CI介导。这些结果为水性表面反应性物种的鉴定开辟了一条新途径，并有助于理解与CIs介导的细胞氧化应激相关的疾病发展。
