Stable nanomagnetic particle dispersions

A method of making targeted nanomagnetic particles, the method comprising:

• (a) obtaining magnetic core particles having a plurality of diameters ranging from about 30 nm to about 500 nm;
• (b) encapsulating the magnetic core particles with a glass layer to form first encapsulated magnetic core particles, wherein the glass layer optionally has a thickness of about 1 nm to about 50 nm;
• (c) encapsulating the first encapsulated magnetic core particles in a composite layer comprising a mixture of a protein and polymer to form second encapsulated magnetic core particles, wherein the composite layer of protein, which is bovine albumin or human albumin and polymer, which is dextran, optionally has a thickness of about 5 nm to about 50 nm, and
• (d) binding, covalently, targeting moieties to the protein and polymer composite layer of the second encapsulated magnetic core particles, wherein the targeting moieties comprise one member of a bioaffinity ligand pair, optionally wherein the targeting moieties are independently selected from the group consisting of antibodies, an antigen-binding antibody fragments, a cell surface receptor, ligand-binding extracellular domains of a cell surface receptor, nucleic acids, avidin, streptavidin, biotin, pharmaceutical compounds for purposes of targeted drug delivery;
• and, optionally,
• (e) binding, optionally covalently, a pharmaceutical compound or detectable label to the second encapsulated magnetic core particles.