辅酶Q10的气相分裂由APCI产生的基离子:通过高/低分辨率并列/序列质谱法进行的一项研究
Mariachiara Bianco, Ilario Losito, Giovanni Ventura
1Dipartimento di Scienze del Suolo, della Pianta e degli Alimenti, Università degli Studi di Bari Aldo Moro, Via G. Amendola 165/a, 70126 Bari, Italy.
Journal of the American Society for Mass Spectrometry
|January 20, 2025
概括
这项研究详细介绍了使用质谱学的辅酶Q10碎片化模式. 对CoQ10和相关化合物的新见解.
科学领域:
- 生物化学和分析化学,专注于辅酶Q化合物.
背景情况:
- 辅酶Q10 (CoQ10) 和它的类似物是细胞呼吸和能量生产的重要生化辅因子.
- 液体染色学-质谱学 (LC-MS) 是食品和生物矩阵中的CoQ10分析的标准.
- 在APCI-MS中普遍存在的CoQ10基离子的详细碎片化途径仍未得到充分研究.
研究的目的:
- 系统地研究和阐明辅酶Q10基离子 ([M]•−) 的碎片化机制.
- 为了识别由CoQ10碎片化产生的特征性产品离子.
- 评估这些碎片化模式在复杂样本中识别相关CoQn化合物的适用性.
主要方法:
- 使用高分辨率里埃变换质谱法 (FTMS) 的高碰撞能量解离 (HCD).
- 使用碰撞诱导解离低分辨率序列质谱法 (CID-MSn,n=2-4).
- 应用密度函数理论 (DFT) 计算来验证拟议的产品离子结构.
主要成果:
- 解释了各种碎片化途径,包括甲基损失和C-C键在异烯酸侧链中的同解裂.
- 假设形成稳定的迪斯通基离子和随后的分子内循环.
- 确定了对CoQ10和其他CoQn衍生物 (n=7-9) 共同的诊断产品离子.
结论:
- 阐明了辅酶Q10基离子的关键碎片化途径.
- 通过特有的质谱碎片化模式建立了识别CoQ10和相关CoQn化合物的基础.
- 通过使用RPLC-APCI-FTMS,证明了这些发现对分析可食用的Brassicaceae微绿植物中的CoQn的实用性.
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