Multi-angle light scattering (MALS) detection has become an indispensible tool for protein characterization. It can be used in the standalone (batch) mode to measure specific or non-specific protein interactions, but often it is used in conjunction with a separation system such as field flow fractionation (FFF) or size exclusion chromatography (SEC). The combined SEC-MALS method has many applications, such as the confirmation of the oligomeric state of a protein, quantification of protein aggregation, and determination of protein conjugate stoichiometry.
SEC columns for protein separation, typically are packed with dextran, agarose, or silica based stationary phases. When a flow of mobile phase is applied, particle fines (often in the range of 10 to 200 nm) can be generated from the column packing and pass though the detectors. These particles may persist for an extended period of time (sometimes days or longer). This phenomenon is known as column shedding or bleeding. These particles are not detected by UV absorption or differential refractive index detection, but cause a significant increase in the baseline noise of a light scattering detector. Many customers, frustrated by excessive down time required to condition columns (or the need to compromise data quality), resort to using post-column filters to remove column particulates. Unfortunately, this can remove a portion of the sample. In order to achieve the best detection sensitivity Wyatt MALS detectors offer, and to improve productivity, it is vital to find an SEC column that will cease shedding particles after of time. columns promise
The scientists at Wyatt Technology have focused their energies to help in the development of a family of new silica based columns specifically designed for SEC MALS protein applications. These columns retain all the important features of a first-class SEC column for protein separations. They are made of the highest quality silica with well-controlled pore size and highly reproducible surface chemistry. As a result, WTC columns provide high resolution, extended lifetime, excellent lot-to-lot reproducibility, and a full range of pore size selections. Moreover, these columns have exceptionally low light scattering baseline noise and better pressure shock resistance than any comparable columns on the market. Each column is individually tested in the Wyatt Technology's Application Lab with a MALS detector prior to shipment and comes with a custom Certificate of Performance.