Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) is an important tool for high-throughput N-glycan profiling and, upon use of tandem MS, for structure determination. By use of MALDI-MS imaging (MSI) in combination with PNGase F treatment, also spatially-correlated N-glycan profiling from tissue sections becomes possible. Here we coupled laser-induced postionization, or MALDI-2, to a trapped ion mobility quadrupole time-of-flight mass spectrometer (timsTOF fleX MALDI-2, Bruker Daltonics). We demonstrate that negative ion mode MALDI-2-MSI is capable of providing high quality N-glycan tissue distributions. Combined with the advantageous fragmentation behavior of [M–H]– ions, exceedingly rich structural information on the composition of complex N-glycans was moreover obtained directly from thin tissue sections of human cerebellum and upon use of low-energy collision-induced dissociation tandem MS. Providing a complete package for MS-based glycan research, MALDI-2 will become a valuable tool in glycobiology research.
建立在 shotgun 蛋白组学标准上的 timsTOF fleX 将布鲁克一流的 4D-组学分析与尖端的 MALDI 成像技术整合于一个平台,包括高频率的 smartbeam 3D 激光器。配置有双离子源的 timsTOF fleX,把持久稳定的 ESI 分析和组织分子空间分布集成于一体,是进行空间定位组学研究的理想平台。在此之前,没有质谱仪能为组学研究者同时提供这两种能力。
ESI 和 MALDI 的切换操作,只需在软件中开启 smartbeam 3D 激光源,仅需几秒即可完成。简单的切换操作意味着从组学深度鉴定和定量流程到组织高清成像的方便转换,又不影响效率和功能,从而发现真正有用的信息。
增加 MALDI 成像新维度,挖掘更多信息
由 MALDI 和 ESI 产生的离子,经过同一路径从离子源到达探测器,因此 MALDI 工作流程可以利用 timsTOF HT 的主要优势,包括根据分子碰撞截面 ( CCS ) 来进行捕集离子淌度分离( trapped ion mobility separation,TIMS )。调谐和校准可在 ESI 模式下进行,并用于 MALDI 模式,方便了仪器的优化。