Antigens, Antibodies and Blocking Reagents Medix Biochemica is a manufacturer and supplier of high quality antigens, antibodies, universal non-mammalian blocking reagents, and specialized immunoassay reagents for the in vitro diagnostic (IVD) manufacturing industry worldwide, as well as research institutes. Medix Biochemica continues to expand their product range of cardiac markers, drug of abuse (DOA) , hormones, infectious diseases, serum proteins, tumor markers and veterinary products.