Patent ID: 7175912

Claim:
A super-paramagnetic composite particle with core/shell structure capable of labeling biological materials or nonbiological materials, comprising: a core portion and a shell portion coated on the surface of the core portion, wherein the core portion is consisted of magnetic materials, the shell portion is consisted of noble metal materials, characterized in that the composite particle has an average diameter of 0.05–50 μm, the core portion is 10–70% by weight and said shell portion is 30–90% by weight based on the total weight of the composite particle, wherein the core portion is consisted of magnetic particles selected from Fe 3 O 4 , γ-Fe 2 O 3 , bivalent manganese ferrite, bivalent nickel ferrite, bivalent zinc ferrite and bivalent copper ferrite, and the shell portion is a layer of noble metal with thickness of 0.020˜20 μm.