Surface modification of permalloy (Ni80Fe20) nanoparticles for biomedical applications

We report a simple and novel method for surface biofunctionalization onto recently reported NiFe permalloy nanoparticles (~71 nm) and the immobilization of a model protein, IgG from human serum. The strategy of protein immobilization involved attachment of histidine-tagged streptavidin to the NiFe nanoparticles via a non-covalent ligand binding followed by biotinylated human IgG binding on the nanoparticle surface using the specific high affinity avidin-biotin interaction. The biofunctionalization of NiFe permalloy nanoparticles was confirmed by Fourier Transform InfraRed (FTIR) spectroscopy and protein denaturing gel electrophoresis (lithium dodecyl sulfate- polyacrylamide gel electrophoresis, LDS-PAGE). This protocol for surface functionalization of the novel nanometer-sized NiFe permalloy particles with biological molecules could open diverse applications in disease diagnostics and drug delivery