Investigating Differences in Gas-Phase Conformations of 25-Hydroxyvitamin D3 Sodiated Epimers using Ion Mobility-Mass Spectrometry and Theoretical Modeling
Investigating Differences in Gas-Phase Conformations of 25-Hydroxyvitamin D3 Sodiated Epimers using Ion Mobility-Mass Spectrometry and Theoretical Modeling
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DOI：
10.1007/s13361-017-1673-4
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发表时间：
2017-08-01
影响因子：
3.2
通讯作者：
Yost, Richard A.
中科院分区：
文献类型：
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作者：
Chouinard, Christopher D.;Cruzeiro, Vinicius Wilian D.;Yost, Richard A.
采用漂移管离子迁移率-质谱法研究了25-羟基维生素D3(25OHD3)和D2(25OHD2)异构体的气相结构，并评价了其在快速分离这些化合物方面的潜力。实验结果表明，25OHD3碱化单体有两种不同的漂移物种，而其同分异构体(Ep25OHD3)只有一种构象。这种独特的物种使得25OHD3很容易区分，25OHD2同分异构体也观察到了同样的模式。25OHD3异构体的理论模型确定了能量稳定的气相结构，表明这两个化合物都可能采用紧凑的“封闭”构象，但25OHD3也可能采用能量稍低的“开放”构象，而它的同分异构体不能进入。这些结构的理论碰撞截面的计算结果与实验结果一致
Drift tube ion mobility coupled with mass spectrometry was used to investigate the gas-phase structure of 25-hydroxyvitamin D3 (25OHD3) and D2 (25OHD2) epimers, and to evaluate its potential in rapid separation of these compounds. Experimental results revealed two distinct drift species for the 25OHD3 sodiated monomer, whereas only one of these conformations was observed for its epimer (epi25OHD3). The unique species allowed 25OHD3 to be readily distinguished, and the same pattern was observed for 25OHD2 epimers. Theoretical modeling of 25OHD3 epimers identified energetically stable gas-phase structures, indicating that both compounds may adopt a compact "closed" conformation, but that 25OHD3 may also adopt a slightly less energetically favorable "open" conformation that is not accessible to its epimer. Calculated theoretical collision cross-sections for these structures agreed with experimental results to