Integrated liquid chromatography-multiangle light scattering system to measure mass and size of biological macromolecules

在分析蛋白质和多糖等基本生物分子时，大小是基本信息的关键部分。对于蛋白质，形成同源寡聚体或异源寡聚体（即与其他伴侣）或与配体相互作用的能力是功能始终必不可少的特性。对于多糖，大小通常决定了它们在生物系统中的功能特性，或它们作为商业产品的应用。虽然概念简单，但通过尺寸排阻色谱法测量生物大分子的尺寸由于包括大分子与柱基质的相互作用、可能与可用标准品完全不同的构象、低聚或聚集以及样品中的异质性的因素而复杂化。这些限制可以通过整合尺寸排阻色谱和多角度光散射（SEC-MALS）来克服。所要求的OMNISEC系统包括一个专用的液相色谱平台，该平台集成了20角光散射检测器，以及光电二极管、折射率检测器和粘度检测器，这些检测器集成了来自各种生物物理参数的数据。该系统提供摩尔质量和均方根半径（r）的绝对测量

In the analysis of essential biological molecules, such as proteins and polysaccharides, size is a critical piece of fundamental information. With proteins, the ability to form homooligomers or heterooligomers (i.e. with other partners), or to interact with ligands, are properties that are invariably essential for function. For polysaccharides, size generally determines their functional properties in biological systems, or their applications as commercial products. While simple in concept, measuring the size of biological macromolecules by size exclusion chromatography is complicated by factors including interaction of the macromolecule with the column matrix, a conformation that may be quite different to available standards, oligomerization or aggregation, and heterogeneity in the sample. These limitations can be overcome by integrating size exclusion chromatography and multi-angle light scattering (SEC-MALS). The requested OMNISEC system includes a dedicated liquid chromatography platform integrated with a 20-angle light scattering detector, as well as photodiode, refractive index detector, and viscometry detectors integrating data from a wide range of biophysical parameters. This system affords an absolute measurement of molar mass and rms radius (r