Magnetizable composite particles based on cross-linked organopolysiloxane, process for preparation thereof and their application in biology

摘要

Magnetizable composite particles, optionally in aqueous dispersion, consisting of a matrix based on a crosslinked organopolysiloxane, optionally bearing nonvinyl reactive and/or ionic units and magnetizable components less than 300 angstroms in diameter encapsulated in the matrix. The magnetizable composite particles are prepared by homogenizing a solution of the organopolysiloxane, an organohydrogenpolysilioxane optionally bearing ionic and/or reactive units, and a magnetic fluid, in the presence of water and a surfactant, performing a hydrosilylation in an aqueous emulsion, removing the organic solvents and the organic carrier liquid, and at least partially removing the water. The magnetizable composite particles are useful in biological applications.