一个光谱测试表明,MS/MS库中的碎片离子结构注释经常是不正确的
Lara van Tetering1, Sylvia Spies1, Quirine D K Wildeman1
1Radboud University, Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld 7, 6525ED, Nijmegen, The Netherlands.
Communications chemistry
|February 15, 2024
概括
In silico MS/MS光谱预测对于识别未知的分子至关重要. 然而,这项研究表明,常见的in silico图书馆含有不正确的碎片离子结构,妨碍了准确的分子识别.
科学领域:
- 分析化学 分析化学
- 频谱学是一种光谱学.
- 计算化学计算化学
背景情况:
- 高分辨率质谱 (MS) 可以识别成千上万种化合物,但完全的结构阐明仍然具有挑战性.
- 碰撞诱导解离双重质谱法 (CID-MS) 有助于通过图书馆搜索或de novo预测进行结构识别.
- 在 silico MS2 频谱对于 de novo 识别至关重要,但它们的准确性仍有争议.
研究的目的:
- 为了评估 in silico产生的MSn产品离子结构的准确性.
- 用红外离子光谱法 (IRIS) 将片离子结构与实验确定结构进行比较.
- 评估主要in silicoMS2光谱库用于分子结构注释的可靠性.
主要方法:
- 在基生成MSn产品离子结构.
- 使用红外离子光谱学 (IRIS) 实验确定碎片离子结构.
- 在五个前体分子中,与IRIS建立的结构对比in silico生成的结构.
主要成果:
- 在in silico预测和实验验证的碎片离子结构之间发现了显著的差异.
- 在主要的in silico MS2库 (HMDB,METLIN,mzCloud) 中几乎所有碎片离子结构注释都被发现是不正确的.
- 该研究强调了当前in silico碎片化算法和光谱库的关键局限性.
结论:
- 目前的in silico MS2库对于准确的碎片离子结构注释是不可靠的.
- 这些发现警告研究人员不要使用这些图书馆来重新识别分子结构.
- 进一步开发精确的in silico碎片化预测工具是必要的,以推进基于质谱的结构阐明.
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