Carbon-Metal Nanoencapsulates
Chemists at TDA are developing an exciting new
class of nanomaterial, the metal-carbon nanoencapsulates, for use in medical and
other commercial applications. The special properties of nanoencapsulates will
potentially allow them to outperform existing technology in areas as diverse as
superparamagnetic magnetic resonance imaging (MRI) contrast enhancing agents,
radiopharmaceuticals, and magnetic data recording media.
The widely variable metal nanocrystal located inside of these materials is continuously coated by an onion-like surface of multi-layer graphitic carbon. This impervious carbon coating protects sensitive metal nanocrystals from the ravages of oxygen and water as well as preventing release of potentially toxic metal(s) to biological media in medical applications. The carbon coating also provides a versatile scaffolding for surface chemical derivatization.
Shown here is a STEM image of a typical magnetic-metal nanoencapsulate produced at TDA. This approximately 20 nm diameter nanoencapsulate has a clearly discernable multi-layer graphitic carbon shell continuously covering the interior metal nanocrystal. Nanoencapsulates with different size interior nanocrystals, metal content and carbon coating thickness can be generated and TDA is developing proprietary production processes for generating metal-carbon nanoencapsulates in larger quantities on a continuous scale.
TDA specializes in the surface derivatization chemistry and solubilization of the metal-carbon nanoencapsulates. Imparting solubility it is key to exploiting their applications, as in an underivatized state they are insoluble. New advances at TDA to modify the otherwise graphitic carbon surface of the metal-carbon nanoencapsulates have overcome this limitation.