Synthesis and characterization of gold nanoparticles conjugated magnetite nanoparticles via Phosphonic acid linkage

The conjugation of gold nanoparticles (GNPs) with magnetite nanoparticles is achieved in a two step process in which the initial step is a self-assembled monolayer of mercaptoundecanol on conjugation to GNPs by reducing HAuCl₄ to obtain wine color suspension of hydroxyl capped GNPs. The reaction is further proceeded with phosphorus oxychloride, followed by hydrolysis, in which the final step would be anchoring to magnetite nanoparticles by sonication. The nanometer sized core-shell hybrid materials having a GNPs core with a ligand - shell conjugated magnetite nanoparticles in an ambient temperature have been prepared in a facile synthetic manner. The grafting reaction is then confirmed using ultraviolet-visible spectroscopy, X-ray diffraction, transmission electron a microscopy and Infrared spectroscopy. This new approach of conjugating of two metal nanoparticles in a single linkage ligand will have a fascinating approach in biomedical application.