Working with magnetic separation rack? Keep reading!
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.
When biomagnetic particle kits are initially developed, R&D companies work with small volumes in a magnetic separation rack in order to test and optimize a number of variables. When the kit is deemed successful, the company obviously wants to take the kit to market and consequently ramp up production.
The concentration of magnetic beads is an important step in a magnetic separation process. Separation time is dependent on magnetic bead concentration, and final kit performance is also very dependent on accurate concentrating techniques, but liquid handling inaccuracies can lead to serious errors. If these concentration errors are not detected early in the process, excessive time, money and effort will need to be spent to either correct or redo the batch.
When one scales up production using a classic magnetic separation system, one finds that the separation time increases quickly with an increase in production volume. An increase in separation time means that material losses are higher and aggregation problems become a serious problem. By using homogenous separation time, one finds that the magnetic separation process is shorter and the separation time can be easily estimated. In homogeneous systems material loss and bead aggregation is minimized.
In the Life Sciences, one of the most critical parameters for final IVD kit performance is magnetic bead concentration. The beads are functionalized before the magnetic separation process with antibodies or other biological molecules, so the concentration of magnetic beads also delivers a specific concentration of biologically active reagent. If you do not have the correct amount of beads/biological molecules in your preparation, the sensitivity of the kit changes significantly. Therefore volume control of the suspension is quite important.
In non-homogenous magnetic separators, monitoring the entire separation process is difficult to impossible. As a result, errors in the magnetic separation process, such as using the wrong magnetic beads or using buffers with the wrong properties are not detected until the final QC testing stage.
When magnetic bead reagents are produced in quantity, often you cannot know if you have the correct properties of the beads until the final quality control step. But if these properties are wrong, finding out the properties at the end of the magnetic separation process for production does not allow you to salvage the lot. Knowing magnetic bead properties, such as size, magnetic charge and surface charge, is critical in order to have excellent reproducibility in the final product (e.g. IVD kits).
If scientists and technicians link their production results solely to the separation time on one specific piece of classic biomagnetic separation equipment, they will not be able to translate that success. This is applied to both different batch sizes or even the same batch size on a different piece of equipment, unless they optimize the separation time for the new conditions.
When a lab has finally optimized their production process, they often link their process to a very specific piece of equipment and, by extension, have locked themselves into a constant volume. Often a lab develops its magnetic separation process for production with a specific magnetic separation device – this is normal. Usually the only parameter that needs to be adjusted during production is the separation time.