Magnetizable composite microspheres of hydrophobic crosslinked polymer, process for preparing them and their application in biology

摘要

Magnetizable composite microspheres approximately from 0.05 to 10 mu m in diameter, comprising a core of magnetizable particles and a shell of a hydrophobic crosslinked copolymer formed from a vinylaromatic monomer and a crosslinking emulsifying polymer. The microspheres are obtained by the pre-emulsification in water of a magnetic fluid composed of magnetizable particles dispersed in a vinylaromatic monomer and in a crosslinking emulsifying polymer, polymerization, separation of the magnetizable microspheres and optional redispersion in water. The microspheres are useful in biological applications.