Abstract: This invention provides a novel process of producing magnetically responsive polymer particles comprising polymeric core particles coated evenly with a layer of polymer containing magnetically responsive metal oxide. A wide variety of polymeric particles with sizes ranging from 1 to 100 microns can be used a core particles and transformed into magnetically responsive polymer particles. The surface of these magnetically responsive polymer particles can be coated further with another layer of functionalized polymer. These magnetically responsive polymer particles can be used for passive or covalent coupling of biological material such as antigens, antibodies, enzymes of DNA/RNA hybridization and used as solid phase for various types of immunoassays, DNA/RNA hybridization probes assays, affinity purification, cell separation and other medical, diagnostic, and industrial applications.