Magnetic microspheres prepared by redox polymerization used in a cell separation based on gangliosides

A facile method is described for making magnetic microspheres that bind specifically to cell surfaces, in order to separate cells magnetophoretically. Control over the sizes of the spheres is effected by using their magnetic cores as part of a redox polymerization system. The use of the microspheres is demonstrated with a separation involving C-1300 neuroblastoma cells, 10% of which express the ganglioside GM1 in their membranes. The GM1-containing cells were separated with better than 99% purity, while the deficient cells were obtained at least 98% pure. The separation, which was carried out under sterile conditions, required only 6 minutes.