Step-like magnetoresistance change of spin-valve based sensor for direct magnetic Fe3O4/Ag hybrid nanoparticles detection

A hybrid of nanomagnetic Fe3O4 and antibacterial nanomaterial such as Ag is one the promising nanoparticles for magnetoresistance-based biosensor. Therefore, we are developing a biosensor system to quantize biomolecule concentration via Fe3O4/Ag nanohybrid detection using spin-valve thin-film sensing element. In this research, magnetic was synthesized co-precipitation/aqua-solution method. During induced by low field (about 10-15 Gauss), step-like magnetoresistance change element observed. Embedding on nanoparticle induces 32% magnetization saturation reduction which successfully enhances ratio 3%. The exhibits linear decreasing increased attached its surface. Furthermore, stray-field presence from also indicated switching shifting. By linking specific receptor agent, can be assigned biocompatible label in merger with magnetic-based application.