Superparamagnetic colloidal photonic structures
US10118834B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 26, 2008 |
| Grant date | Nov 6, 2018 |
| Priority date | — |
| Expiry date | Apr 26, 2028 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F2202/32
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
Monodisperse colloidal nanocrystal clusters of magnetite (Fe3O4) with tunable sizes from about thirty to about three hundred nanometers have been synthesized using a high-temperature hydrolysis process. The colloidal nanocrystal clusters are capped with polyelectrolytes, and highly water soluble. Each cluster is composed of many single magnetite crystallites, thus retaining the superparamagnetic behavior at room temperature. The combination of superparamagnetic property, high magnetization, and high water dispersibility makes the colloidal nanocrystal clusters ideal candidates for various important biomedical applications such as drug delivery and bioseparation. The present invention is further directed to methods for forming colloidal photonic crystals from both aqueous and nonaqueous solutions of the superparamagnetic colloidal nanocrystal clusters with an external magnetic field applied thereto. The diffraction of the photonic crystals can be tuned from near infrared to visible and further ultraviolet spectral region by varying the external magnetic field.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.