| abstract |
(57) Abstract The present invention relates to superparamagnetic single domain particles with increased R 1 relaxation and surface stabilizing substances. Particles of iron hydroxide, iron oxide hydrate, iron oxide, made from a mixed oxide of iron or an iron, a size of 1 to 10 nm, the average particle diameter d 50 of be 2 to 4 nm; 2 to 50 of the It is characterized by having increased R 1 relaxation and a relaxation ratio R 1 / R 2 of less than 5. Stabilizers bind to the particle surface; they prevent aggregation and sedimentation in gravitational and magnetic fields. If desired, the particles may also include a tissue-specific binding agent, a pharmacologically active agent, a pharmacologically active cell, a pharmacologically active chelator, a cell fusion or gene transfer mediator, or a mixture of those materials. it can. The novel particles can be used for tumor attack, immune boosters, cell fusion, gene transfer, or, if necessary, as contrast agents in magnetic resonance diagnostics using magnetic fields. |