Coated chromium dioxide particles.

摘要

Chromium dioxide has favourable magnetic properties which make it desirable as a solid support in heterogeneous immunoassays. However, to be useful in such assays it must be protected against hydrolytic degradation. This invention provides magnetic particles useful in immunoassays having a core of CrO2 which has a reduced surface, the core coated with silica and further coated with a silane.