The synthesis of GoldMag nano-particles and their application for antibody immobilization.

Fe3O4/Au (GoldMag) particles with core/shell structure were synthesized by reduction of Au3+ with hydroxylamine in the presence of Fe3O4. The synthesized particles have an average size smaller than 100 nm in diameter with of superparemagnetic properties due to their Fe oxide cores. The particles show optical features with a plasmon resonance peak from 550, 570 to 590 nm correlating with increasing diameters from 50 nm, 70 nm to 100 nm. The GoldMag particles need only a single step for antibody immobilization and have high binding capacity for antibodies. These advantages permit improved methods of isolating and detecting biomolecules.