When a non-homogenous magnetic separation rack (a classical system) is used for scaling up a process, the conditions for a larger batch will completely change from the smaller batch. In these classical non-homogeneous magnetic separator, both the magnetic field gradient and the magnetic state of the beads (either linear or saturated) will vary depending on their position and relative distance to the magnet.
Well-established classical detection methods that are packed in kit form include Radioimmunoassays (RIAs) or Enzyme Linked Immunoassays (ELISAs). These two detection methods were highly sensitive and used for a variety of biological and chemical testing. Even though RIAs are very sensitive assays, by their very nature, they are comprised of highly hazardous, radioactive reagents. The handling and disposal of RIA refuse can be difficult to regulate in the lab environment as well as expensive.
While it might be thought that ‘bigger is better’ during a scale-up process, merely using a larger magnet in a magnetic separation rack for larger volumes generates very different conditions. This leads to inconsistencies and other problems with the final product.
Retrieving analytes from their original sources (especially when working on proteins) can be tricky and difficult. In addition, various methods of analyte recovery are highly concentration dependent. For example, analytes can be extracted from very concentrated samples, e.g. greater than or equal to 1 mg/ml, with methods such as nephelometry or turbidmetry. Lower concentrations such as 1 ug/ml require the use of an ELISA or Immunofluorescence assays to isolate the desired analyte.
Magnetic bead separation has become a very popular technique in life sciences. Magnetic bead separation is a quick, efficient, clean process that scientists use instead of filtration, centrifugation and separation techniques.
Working with magnetic separation rack? Keep reading!
Irreversible aggregation is one of the main concerns when functionalizing magnetic beads for use in diagnostic and biotech applications. The presence of aggregates can cause high variability in the functionality of the magnetic beads and large inconsistencies. Irreversible aggregation causes serious problems when one tries to resuspend the particles after the processing, coupling and washing steps. Because of this, as we have explained in previous posts, one of the best ways to solve this issue is using the sonication method.
Do you want to learn how to take the most of your magnetic separation rack? There are lots of common mistakes related to the scale-up of biomagnetic separation processes, and lots of them imply the use of non-homogeneous magnetic racks.
