William Marsh Rice University

Richard D Averitt

Nancy J Halas

Steven J Oldenburg

Jennifer L West

Scott R Sershen

The present invention is for particulate compositions and methods for producing them that can absorb or scatter electromagnetic radiation. The particles are homogeneous in size and are comprised of a nonconducting inner layer that is surrounded by an electrically conducting material. The ratio of the thickness of the nonconducting layer to the thickness of the outer conducting shell is determinative of the wavelength of maximum absorbance or scattering of the particle. Unique solution phase methods for synthesizing the particles involve linking clusters of the conducting atoms, ions, or molecules to the nonconducting inner layer by linear molecules. This step can be followed by growth of the metal onto the clusters to form a coherent conducting shell that encapsulates the core.

Nanoparticle comprising nanoshell of thickness less than the bulk electron mean free path of the shell material

The present invention provides nanoshell particles (&ldquo;nanoshells&rdquo;) for use in biosensing applications, along with their manner of making and methods of using the nanoshells for in vitro and in vivo detection of chemical and biological analytes, preferably by surface enhanced Raman light scattering. The preferred particles have a non-conducting core and a metal shell surrounding the core. For given core and shell materials, the ratio of the thickness (i.e., radius) of the core to the thickness of the metal shell is determinative of the wavelength of maximum absorbance of the particle. By controlling the relative core and shell thicknesses, biosensing metal nanoshells are fabricated which absorb light at any desired wavelength across the ultraviolet to infrared range of the electromagnetic spectrum. The surface of the particles are capable of inducing an enhanced SERS signal that is characteristic of an analyte of interest. In certain embodiments a biomolecule is conjugated to the metal shell and the SERS signal of a conformational change or a reaction product is detected.

Metal nanoshells for biosensing applications

Metal nanoshells

A thermally sensitive polymer-particle composite that absorbs electromagnetic radiation, and uses the absorbed energy to trigger the delivery of a chemical is disclosed. Metal nanoshells are nanoparticulate materials that are suitable for use in the present composites and can be made according to a process that includes optically tuning or tailoring their maximum optical absorption to any desired wavelength primarily by altering the ratio of the core diameter to the shell thickness. Preferred nanoshells are selected that strongly absorb light in the near-infrared and thus produce heat. These nanoshells are combined with a temperature-sensitive material to provide an implantable or injectable material for modulated drug delivery via external exposure to near-IR light. This invention provides a means to improve the quality of life for persons requiring multiple injections of a drug, such as diabetes mellitus patients.

Growing community of inventors

Houston, TX, United States of America

Richard D Averitt