Department of Chemistry, Boston University, Boston, MA, 02215, USA.
Center for Biomedical Mass Spectrometry, Boston University School of Medicine, Boston, MA, 02118, USA.
J Am Soc Mass Spectrom. 2018 Jun;29(6):1295-1307. doi: 10.1007/s13361-018-1943-9. Epub 2018 Apr 13.
The occurrence of numerous structural isomers in glycans from biological sources presents a severe challenge for structural glycomics. The subtle differences among isomeric structures demand analytical methods that can provide structural details while working efficiently with on-line glycan separation methods. Although liquid chromatography-tandem mass spectrometry (LC-MS/MS) is a powerful tool for mixture analysis, the commonly utilized collision-induced dissociation (CID) method often does not generate a sufficient number of fragments at the MS level for comprehensive structural characterization. Here, we studied the electronic excitation dissociation (EED) behaviors of metal-adducted, permethylated glycans, and identified key spectral features that could facilitate both topology and linkage determinations. We developed an EED-based, nanoscale, reversed phase (RP)LC-MS/MS platform, and demonstrated its ability to achieve complete structural elucidation of up to five structural isomers in a single LC-MS/MS analysis. Graphical Abstract.
生物来源的聚糖中存在大量结构异构体，这对结构糖组学提出了严峻的挑战。异构体结构之间的细微差异需要分析方法，这些方法能够在与在线糖分离方法高效配合的同时提供结构细节。尽管液相色谱-串联质谱（LC-MS/MS）是一种用于混合物分析的强大工具，但常用的碰撞诱导解离（CID）方法在 MS 水平上通常不能产生足够数量的碎片，无法进行全面的结构表征。在这里，我们研究了金属加合物、全甲基化聚糖的电子激发解离（EED）行为，并确定了关键的光谱特征，这些特征有助于拓扑和连接的确定。我们开发了一种基于 EED 的纳米反相（RP）LC-MS/MS 平台，并证明了它能够在单个 LC-MS/MS 分析中实现多达五种结构异构体的完全结构阐明。
