在中国传统医学中通过密度函数理论和离子碎片模拟软件QCxMS识别异构体
Shuai Wang1, Chuhui Lin1, Linghao Zhao1
1Shanghai Key Laboratory of Functional Materials Chemistry, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China.
Journal of chromatography. A
|June 28, 2024
概括
计算化学有助于在电喷离子化质谱法 (ESI-MS) 中区分异构体. QCxMS软件精确建模了光谱,揭示了碎片化路径和能量,以便更好地识别异构体.
科学领域:
- 分析化学 分析化学
- 计算化学的计算化学
- 药理学 药理学是指药理学的学科.
背景情况:
- 由于细微的光谱差异,在电喷离子质谱法 (ESI-MS) 中区分异构体具有挑战性.
- 计算化学提供了一个解决方案来弥合实验数据和理论理解.
研究的目的:
- 使用计算方法建模和比较异构体的ESI-MS光谱.
- 为了确定主要碎片,并推断出来自Zhishi Xiebai Guizhi Decoction的11种化合物的碎片化途径.
- 为了研究计算的碎片能量和观察到的碎片丰度之间的一致性.
主要方法:
- 使用QCxMS软件进行质谱 (MS) 分片模拟.
- 用于实验数据的超高性能液态染色学-飞行质谱四极时 (UPLC-Q-TOF-MS).
- 应用密度函数理论 (DFT) 来计算碎片化能量.
主要成果:
- 在参数优化后,QCxMS成功地为所有11个检查的同位素生成了可靠的光谱.
- 在GFN1-xTB和GFN2-xTB计算数据之间没有发现显著差异.
- 从理论数据中确定了碎片化的途径和主要碎片.
- 计算的碎片能量与观察到的碎片丰度保持一致,支持热力学和动力学方法.
结论:
- 使用QCxMS的计算建模为ESI-MS中异构体识别提供了可靠的方法.
- DFT计算提高了对异构体特定碎片化机制的理解.
- 这种方法为分析传统中医药等复杂混合物提供了一个精确的理论框架.
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