A Raman detector for Field-Flow Fractionation for advanced in vitro characterization of Macromolecules

本项目旨在建立一套非对称流场分馏(AF4)的拉曼在线检测系统。AF4是一种分离大分子的方法，它还可以测定扩散系数的分布。流体力学尺寸的范围从1纳米到100微米。电流检测器得到摩尔质量和相对样品浓度的分布。此外，还可以测量复杂混合物中每个组分的UV-Vis或荧光光谱。建议的拉曼检测引入了获得关于样品的化学性质的信息的可能性。通过这种方法，复杂混合物中的分级样品可以仅通过化学基团来区分，而不需要任何标记，因为这是使用UV-Vis和荧光检测器区分许多样品所必需的。与我们的建议类似的方法只有在巨额财务支出和严格限制可用的洗脱溶剂数量的情况下才可用。即使是完全未知的样品的单一成分也可以被分离，并在拉曼光谱中识别它们的化学基团。拉曼检测器应用商业上可获得的标准蛋白质和小分子、核酸或碳水化合物的蛋白质络合物进行测试。此外，还应研究核壳纳米颗粒上的稳定剂分子，因为它们的原位化学组成应该为纳米颗粒合成的优化提供有价值的信息，这是现有方法无法正确获得的。

This project aims to set up an on-line Raman detection system for asymmetrical-flow field flow fractionation (AF4). AF4 is a separation method for macromolecules, which also allows the determination of distributions of the diffusion coefficient resp. the hydrodynamic size over a range from 1 nm to 100 micro meters. Current detectors yield distributions of the molar mass and the relative sample concentrations. Also UV-Vis or fluorescence spectra for each component in complex mixtures can be measured. The proposed Raman detection introduces the possibility to gain information about the chemical nature of the sample. By this way, fractionated samples in complex mixtures could be distinguished solely by chemical groups without requiring any labelling as it is necessary for the distinction of many samples using UV-Vis and fluorescence detectors. Comparable methods to our proposal are only available under enormous financial expenses and with a strictly limited number of usable elution solvents. Even the single components of completely unknown samples could be fractionated and their chemical groups be identified in the Raman spectra. The Raman detector shall be tested with commercially available standard proteins and protein complexes with small molecules, nucleic acids or carbohydrates. Also, stabilizer molecules on core-shell nanoparticles shall be investigated as their chemical composition in situ should deliver valuable information for the optimization of nanoparticle synthesis, which cannot be obtained properly by existing methods.