Synthesis, Properties and Biomedical Applications of Hydrophilic Functional, Polymeric Immunomicrospheres

Imunomicrospheres consist of hydrophilic cross-linked particles with antibodies bound to their surface. These particles find specific receptors on living or fixed cells and therefore can label cell sub-populations and the labelled cells can be observed by means of a scanning electron or light-microscope. To label . cells with polymeric particles, biocompatible microspheres are neded preferably with a narrow distribution of sizes in the range of 10 to 10,000 A. Several classes of hydrophilic cross-linked microspheres with functional groups e.g. carboxyl, hydroxyl, amide and/or pyridine groups were synthesized. These functional groups were used to bind covalently antibodies and other proteins to the surface of the microspheres. To optimize the derivatization technique, polyglutaraldehyde itmiuno. microspheres have been prepared and utilized. Specific populations of human and murine lymphocytes were labelled with microspheres synthesized either by the emulsion or the ionizing radiation technique. The labelling of the cells be means of microspheres containing an iron core led to a successful separation of B from T lymphocytes by means of a magnetic field.