Collaborative Research: Applying Ion-Exchange Chromatography-Supercritical Fluid Chromatography to Small Molecule Analysis

在化学系化学测量和成像项目的支持下，来自圣刘易斯大学和罗文大学的James Edwards和James Grinias教授小组分别致力于通过设计改进的方法来改进对复杂混合物（如废水污泥和血液）中化学物质的分析，以便在识别和定量之前对成分进行物理分离。 该方法利用了一种新的“绿色化学”为基础的技术，减少了对昂贵的和潜在的有害溶剂的依赖。 该团队还设计了一系列样品预处理，旨在提高分离效率和后续分析。 分析方面的改进将加强对环境和生物现象的测量和了解。该合作正在向本科生和研究生介绍复杂的化学系统和表征工具，从而加强对下一代劳动力的培训。小分子和代谢物的分析在很大程度上受到分离系统性能的限制。Edwards和Grinias实验室联合开发的方法能够预浓缩衍生的小分子，然后根据分析物结构进行色谱分离。具体而言，该方法需要开发二维（2D）离子交换-超临界流体色谱（IEX-SFC）分离系统。在这种方法中，小分子用阳离子芳香族标签衍生化，这使得它们能够在IEX柱上预浓缩。使用有机溶剂而不是盐来除去IEX使得洗脱液与SFC和质谱（MS）相容。然后，SFC基于亲水相互作用解析分析物，独立于（尽可能）标签。正在开发具有多方面梯度（有机溶剂和温度）的全孔IEX-SFC系统和基于毛细管的SFC系统。此外，正在开发一种新的纳米喷雾接口，以促进MS检测耦合到SFC。该奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

With support from the Chemical Measurement and Imaging Program in the Division of Chemistry, the groups of Professors James Edwards and James Grinias from Saint Louis University and Rowan University, respectively, are working to improve the analysis of chemicals in complex mixtures like wastewater sludge and blood by devising improved methods to physically separate the constituents prior to their identification and quantitation. The approach utilizes a novel "green chemistry" based technique, with reduced dependence on expensive and potentially harmful solvents. The team is also devising a series of sample pretreatments intended to improve both the separation efficiency and the subsequent analysis. The analysis improvements will enhance the measurement and understanding of environmental and biological phenomena. The collaboration is introducing undergraduate and graduate students to complex chemical systems and tools for their characterization, thereby enhancing the training of the next generation of workforce. The analysis of small molecules and metabolites is limited largely by the performance of the separation system. Methods being jointly developed in the Edwards and Grinias laboratories are capable of preconcentrating derivatized small molecules and then chromatographically resolving them based on analyte structure. Specifically, the approach entails development of a two-dimensional (2D) ion exchange-supercritical fluid chromatography (IEX-SFC) separation system. In this approach, small molecules are derivatized with a cationic aromatic tag which allows them to be preconcentrated on an IEX column. Using organic solvent rather than salts to elute off the IEX renders the eluent compatible with SFC and mass spectrometry (MS). The SFC then resolves analytes based on hydrophilic interactions, independent (insofar as possible) of the tag. Both a full-bore IEX-SFC system and a capillary based SFC system are being developed with multi-faceted gradients (organic solvent and temperature). In addition, a novel nanospray interface is being developed to facilitate MS detection coupled to SFC.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.