Extracted arrival time distributions of negative ion CID-derived fragments produced prior to traveling-wave ion mobility separation were evaluated for their ability to provide structural information on N-linked glycans. Fragmentation of high-mannose glycans released from several glycoproteins, including those from viral sources, provided over 50 fragments, many of which gave unique collisional cross-sections and provided additional information used to assign structural isomers. For example, cross-ring fragments arising from cleavage of the reducing terminal GlcNAc residue on Man₈GlcNAc₂ isomers have unique collision cross-sections enabling isomers to be differentiated in mixtures. Specific fragment collision cross-sections enabled identification of glycans, the antennae of which terminated in the antigenic α-galactose residue, and ions defining the composition of the 6-antenna of several of the glycans were also found to have different cross-sections from isomeric ions produced in the same spectra. Potential mechanisms for the formation of the various ions are discussed and the estimated collisional cross-sections are tabulated.

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评估在行波离子迁移率分离之前产生的负离子CID衍生片段的提取到达时间分布，以评估其提供有关N-连接聚糖的结构信息的能力。从多种糖蛋白（包括从病毒来源获得的糖蛋白）释放的高甘露糖聚糖片段化提供了50多个片段，其中许多片段具有独特的碰撞截面，并提供了用于分配结构异构体的其他信息。例如，由于在Man ₈ GlcNAc ₂上还原性末端GlcNAc残基的裂解而产生的交叉环片段异构体具有独特的碰撞截面，可在混合物中区分异构体。特定的片段碰撞横截面能够鉴定聚糖，其触角终止于抗原性α-半乳糖残基，并且还发现定义了几种聚糖的6触角组成的离子与同分异构体具有不同的横截面。离子以相同的光谱产生。讨论了各种离子形成的潜在机理，并列出了估计的碰撞截面。

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