ABSTRACT
A new two-step method for preparation of monodisperse particles was developed by Ugelstad in 1980. The procedure is suitable for making compact, porous, and core-and-shell particles from a wide variety of monomers in particle sizes ranging from 1 to 100 µm. This chapter reviews the results obtained so far with these particles in immunoassays and cell separation. These particles have a core of cross-linked low-density polymer, and a cross-linked hydrophilic shell with hydroxyl groups stemming from hydroxy ethyl methacrylate. Antibody adsorption is initiated by adding the particles in water to the antibody in phosphate-buffered saline. A similar orientation is probably obtained by hydrophobic adsorption since a major hydrophobic region in an antibody molecule is in the hinge region. The slow chemical coupling probably then takes place with available amino groups in the same area of the antibody molecule. The method of preparation of these particles involved the use of modified monosized macroporous particles based upon styrene divinyl benzene.
