Classic magnetic separation equipment requires a large amount of space in order to comply with health and safety regulations. While the magnetic separation process has numerous advantages, the magnetic fields surrounding the devices may be so large that they fall within the ‘danger’ and/or ‘caution’ areas.
The separation time in standard magnetic separation devices is usually determined by analyzing aliquots of solution taken at different times. The problem is that each aliquot gives the technician information about one spatial point in time. Therefore, the design of validation experiments becomes a very complex endeavor.
When scaling up a process using a traditional magnetic separation rack, the percentage of bead and biomolecule losses significantly increases with an increase in volume. One way of dealing with this problem is by applying a higher force at longer distances. But for this to work, you must apply this greater force without increasing the forces in the retention area during the magnetic separation process, in order to avoid irreversible aggregation.
If one wants to scale up production from small lab lots to full-scale large lots, a non-homogenous magnetic separation process will result in lot-to-lot inconsistencies. Homogenous biomagnetic separation conditions, however, guarantee consistent results regardless of production scale.
Biomagnetic separation techniques are faster, cheaper and easier to use than non-magnetic techniques. In addition, when a magnetic separation process is performed under homogenous conditions, these techniques are also scalable and easily validated.
Due to the inherent properties of classic non-homogenous biomagnetic separators, beads can aggregate during the magnetic separation process. When this happens, technicians try to resolve the magnetic beads separation problem by using special resuspension techniques like the sonication method. But problems with resuspension can ultimately lead to end-product variability, especially if aggregation is not detected early.
By Josep Maria Simó, CEO Sepmag
When using biomagnetic separation, in order to ensure the consistency of the resulting product and the process itself, there must be some sort of validation procedure. Validation should be consistent within a given lot, from lot to lot and also when the process is scaled up. The validation procedure should optimally be related to the conditions of magnetic bead separation and not be dependent on any specific device that generates the magnetic field.
Biomagnetic separation used to take place in academic labs, but recently it has become a very industrial application. As processes are scaled up and volumes increase, the investment required for each batch is larger, but the expected economic return is also larger.
Because biomagnetic separation techniques are relatively simple, life science laboratories and industries are quite enamored with them. Indeed, using only magnetic beads and magnetic fields, biomolecules can be captured and extracted from complex media in magnetic bead separation. However, if this application is to be considered practical, it should also be faster than other separation technologies such as chromatography, electrophoresis or centrifugation.
