Applications of New Mass Spectral Techniques

新质谱技术的应用

• 批准号: 7337938
• 负责人: james a kelley
• 金额: --
• 依托单位: DIVISION OF BASIC SCIENCES - NCI
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/7337938
• 关键词: Applications; New; Mass; Spectral; Techniques

Matrix-assisted laser desorption ionization (MALDI) mass spectrometry, electrospray ionization mass spectrometry (ESI/MS), tandem mass spectrometry (MS/MS), on-line liquid chromatography-mass spectrometry (LC/MS), combined capillary electrophoresis (CE) and mass spectrometry, and accurate mass measurement are the techniques of current interest. The off-line combination of MALDI/MS with high-performance liquid chromatography (HPLC) and with CE is under investigation as an alternate approach for the analysis of complex biological and synthetic mixtures. This approach involves automatically collecting and spotting the HPLC eluent on a MALDI sample plate for subsequent MS analysis, which can include accurate mass measurement and post-source decay fragmentation analysis or MS/MS. An advantage of this approach over on-line LC/MS is the generation of an archive of the original separated sample for reanalysis. A similar approach is being applied with CE where on-linesample concentration techniques involving electrophoretic focusing of large-volume sample injections prior to peak collection are being investigated as a preparative-scale method for the off-line combination of CE with high resolution MALDI/MS. Our goal is to automate this process. Preliminary studies of MALDI/MS using special energy-transferring surfaces and direct laser-desorption ionization (LDI) without the presence of a matrix show promise for the rapid analysis of small molecules.Synthetic derivatives built on a constrained diacylated glycerol scaffold (DAG-lactones) have been identified as potent agonists of protein kinase C (PK-C). Depending on the structure of the substituents comprising R1 and R2, these DAG-lactones appear to have some degree of PK-C isozyme specificity. A solid-phase combinatorial approach is being applied in the LMC to investigate chemical diversity at R1 and R2 in order to produce more specific C1 domain ligands. It is important that these synthetic libraries be rapidly characterized and their structures established before biological evaluation. One of the rapid mass spectral approaches employed for the initial characterization of the larger synthetic DAG-lactone libraries is FAB/MS mixture analysis. Analysis of DAG-lactone mixtures correlates directly with individual analysis, substantially reduces the number of samples to be examined, results in enhanced analytical turn-around and is amenable to accurate mass measurement. Flow-injection ESI/MS is not suitable for analysis of these DAG-lactones because of their high lipophilicity and limited basicity. Flow injection-atmospheric pressure chemical ionization produces spectra that consist of MH+ as well as various fragment and solvent-adduct ions. This later approach appears to be complementary to FAB/MS in terms of spectral information. MALDI/MS also appears useful as a tool for the rapid characterization of these small molecule libraries although variable alkali metal ion cationization complicates spectral interpretation. Matrix-less MALDI is currently under investigation as an approach to resolve this problem and provide an even more rapid analysis approach. Our goal is the structural characterization of all 96 library components in one day.

基质辅助激光解吸电离（MALDI）质谱法，电喷雾电离质谱法（ESI/MS），串联质量光谱法（MS/MS），在线液相色谱 - 液相色谱 - 质量质量光谱法（LC/MS），组合毛细管电子（CE）（CE）和质谱的组合量和准确的质量测量值和准确性。 MALDI/MS与高性能液相色谱（HPLC）和CE的离线组合正在研究中，作为分析复杂生物学和合成混合物的替代方法。这种方法涉及在MALDI样品板上自动收集和发现HPLC洗脱液，以进行随后的MS分析，该分析可以包括准确的质量测量和源后源衰减碎片分析或MS/MS。这种方法比在线LC/MS的优点是生成原始分离样品重新分析的档案。在CE中也采用了类似的方法，即在收集峰值之前，正在研究涉及大量大量样品注射的电泳焦点的实面样本浓度技术，以作为一种准备尺度的方法，用于使用高分辨率MALDI/MS的CE离线组合。我们的目标是自动化此过程。使用特殊的能量转移表面和直接激光解析电离（LDI）对MALDI/MS进行初步研究，而没有基质的存在表明对小分子的快速分析有望在受约束的二氧化甘蓝caff骨（Dag-lactone（Dag-lactone）（Dag-lactone）上构建的相结合衍生物已被识别为Potent aginists protent protent od protent protent aginist protent protent oftectect artent。根据包含R1和R2的取代基的结构，这些DAG-LACTONE似乎具有一定程度的PK-C同工酶特异性。在LMC中正在应用固相组合方法，以研究R1和R2的化学多样性，以产生更特定的C1结构域配体。重要的是要迅速表征这些合成文库，并在生物学评估之前建立它们的结构。用于较大合成DAG-LACTONE库的初始表征的快速质谱方法之一是FAB/MS混合物分析。 DAG-LACTONE混合物的分析与单个分析直接相关，大大减少了要检查的样品数量，导致分析转弯的增强，并且可以适应准确的质量测量。流动注射ESI/MS不适合分析这些DAG-LACTONE，因为它们具有高的亲脂性和有限的碱性。流动注入 - 大气压力化学电离产生由MH+以及各种片段和溶剂 - 添加离子组成的光谱。在光谱信息方面，这种后来的方法似乎与Fab/MS是互补的。 MALDI/MS似乎也可以作为这些小分子库快速表征的工具，尽管可变的碱金属离子阳离子使光谱解释复杂化。目前正在调查无基质的MALDI作为解决此问题并提供更快的分析方法的一种方法。我们的目标是一天之内所有96个库组件的结构表征。