[12] Polyacrolein microspheres: Preparation and characteristics

This chapter discusses the preparation and characteristics of polyacrolein (PA). Preparation of polyacrolein microspheres by means of ionizing radiation and preparation of polyacrolein-activated hybrid beads by radiation grafting are discussed. Molecular structures and chemical analyses of PA microspheres are presented. Polyacrolein can be grafted onto preformed microspheres to activate the surface of the preformed microsphere while retaining their original shape. Binding of antibodies to PA microspheres and PA-activated hybrid beads are presented. Acrolein grafting completely changed the binding characteristics of the 11.1-μm compact polystyrene (PS) microspheres. Radiation grafting of PA onto the surfaces of PS spheres, however, allows covalent bonds to be formed with immunoglobulins and will permit four times as much protein to be bound per sphere. The specific labeling of sheep red blood cells (SRBC) with a variety of polymeric spheres of various size and composition after PA is radiation grafted on their surface indicates the scope of this system as a cell marker.