Magnetic beads are a rapid and simple method to purify antibodies from small sample volumes. In contrast to chromatography no complicated setup or instruments are needed. Another advantage is that the method is very flexible – you only need to use as much beads as your sample demands. It is also possible to process several samples in parallel, saving time.
Magnetic beads coated with protein A or G bind IgG from a variety of species and subclasses. They are the primary choice for many purifications of polyclonal and monoclonal antibodies from serum, ascites or hybridoma cell cultures. There are also activated beads that you can couple an antigen to, and then use in immuno-affinity purifications.
Lab on a Bead has developed the LOABeads magnetic agarose beads specially for antibody purification. In a recent benchmark study comparing LOABeads Protein A and other commercial magnetic beads coated with protein A, they performed better than the competitors in all tests. Both binding capacity (at 6 mg IgG/ml bead suspension) and selectivity were higher and the beads were easier to handle.