New Method for Fabricating Monodispersed Fe-oxide@au Nanoparticles in the Range of 5-100nm

Background:
Nanoparticles with tailored magnetic and surface properties are essential for imaging, diagnostics, separations, and targeted therapies, yet existing synthesis methods limit particle diameters to below 15 nm and typically yield only single-core structures. These constraints reduce magnetic responsiveness, restrict functional surface loading, and limit performance in applications requiring larger, tunable particles with strong magnetic manipulation and biocompatibility. A new approach is needed to overcome size limitations, enable multi-core architectures, and maintain flexible, functionalizable surfaces.
Technology Overview:
The invention creates core-shell nanoparticles consisting of multiple discrete, nonconcentric magnetic metal oxide cores encapsulated within a ligand-capped gold or silver shell. Fabrication employs a thermal hetero-interparticle coalescence process in which pre-synthesized core nanoparticles and shell nanoparticles are mixed and heated to 140–160°C, triggering ligand desorption, core coalescence, and re-encapsulation into a monodisperse, tunable particle. Resulting structures range from 5 to 100 nm in diameter and exhibit a “pomegranate-like” morphology, providing strong magnetic responsiveness and a chemically versatile outer shell suitable for biological or catalytic functionalization.
Advantages:

• Enables tunable nanoparticle sizes up to 100 nm for enhanced magnetic performance
• Provides multi-core architecture for stronger magnetic response than single-core particles
• Offers a ligand-capped gold or silver shell for superior biocompatibility and functionalization
• Utilizes a novel hetero-interparticle coalescence approach for precise structural control
• Improves separation efficiency through stronger magnetization and controlled morphology
• Supports targeted biological binding through customizable surface chemistry
• Maintains monodispersity across a wide size range for consistent performance
Intellectual Property Summary:

• United States 8,343,627 - Issued 01/01/2013
• United States 10,006,908 - Issued 06/26/2018
• United States 10,191,042 - Issued 01/29/2019
Stage of Development:
Validated at milligram-scale manufacturing
Licensing Status:
This technology is available for licensing.
Licensing Potential:
Information available upon request.
Additional Information:
Information available upon request.