Northwestern University

Nanosphere, Inc.

Rongchao Jin

Chad A Mirkin

Yunwei Charles Cao

Yun-Wei Cao

Gabriella Métraux

So-Jung Park

Gabriella Metraux

The invention encompasses reagents comprising particles with at least one Raman dye and a specific binding members bound thereto and methods of using such reagents. The invention also encompasses reagents of a specific binding member and two or more different Raman dyes and methods for using such reagents. New types of particle probes having a specific binding member bound thereto are described. These reagents are used in a novel detection strategy that utilizes the catalytic properties of the Au nanoparticles to generate a silver coating that can behave as a surface-enhanced Raman scattering (SERS) promoter for the dye-labeled particles that have been captured by target and an underlying chip in microarray format. The strategy provides the high sensitivity and high selectivity attributes of grey-scale scanometric detection but provides a route to multiplexing and ratioing capabilities since a very large number of probes can be designed based upon the concept of using a Raman tag as a spectroscopic fingerprint in detection. These spectra are used as fingerprints to differentiate oligonucleotide or other targets in one solution. This method has been used to distinguish six dissimilar DNA targets with six Raman labeled nanoparticle probes, and also two RNA targets with single nucleotide polymorphisms (SNPs).

Nanoparticle probes with raman spectroscopic fingerprints for analyte detection

The invention is a novel photo-induced method for converting large quantities of silver nanospheres into nanoprisms, the nanoprisms formed by this method and applications in which the nanoprisms are useful. Significantly, this light driven process results in a colloid with a unique set of optical properties that directly relate to the nanoprism shape of the particles. Theoretical calculations coupled with experimental observations allow for the assignment of the nanoprism plasmon bands and the first identification of two distinct quadrupole plasmon resonances for a nanoparticle. Finally, unlike the spherical particles from which they derive and which Rayleigh light scatter in the blue, these nanoprisms exhibit scattering in the red, permitting multicolor diagnostic labels based not only on nanoparticle composition and size but also on shape.

Methods of making nanoprisms

The present invention provides nanoprisms etched to generate triangular framework structures. These triangular nanoframes possess no strong surface plasmon bands in the ultraviolet or visible regions of the optical spectrum. By adding a mild reducing agent, metal ions remaining in solution can be reduced, resulting in metal plating and reformation of nanoprisms. The extent of the backfilling process can be controlled, allowing the formation of novel nanoprisms with nanopores. This back-filling process is accompanied by a regeneration of the surface plasmon bands in the UV-visible spectrum.

Triangular nanoframes and method of making same

The present invention relates composite core/shell nanoparticles and a two-step method for their preparation. The present invention further relates to biomolecule-core/shell nanoparticle conjugates and methods for their preparation. The invention also relates to methods of detection of biomolecules comprising the biomolecule or specific binding substance-core/shell nanoparticle conjugates.

Non-alloying core shell nanoparticles

The present invention relates composite core/shell nanoparticles and a two-step method for their preparation. The present invention further relates to biomolecule-core/shell nanoparticle conjugates and methods for their preparation. The invention also relates to methods of detection of biomolecules comprising the biomolecule-core/shell nanoparticle conjugates.

Nanoprisms and method of making them

The present invention relates to composite core/shell nanoparticles and a two-step method for their preparation. The present invention further relates to biomolecule-core/shell nanoparticle conjugates and methods for their preparation. The invention also relates to methods of detection of biomolecules comprising the biomolecule or specific binding substance-core/shell nanoparticle conjugates.

The invention provides new types of plasmon-driven growth mechanism for silver nanostructures involving the fusion of triangular nanoprisms. This mechanism, which is plasmon excitation-driven and highly cooperative, produces bimodal particle size distributions. In these methods, the growth process can be selectively switched between bimodal and unimodal distributions using dual beam illumination of the nanoparticles. This type of cooperative photo-control over nanostructure growth enables synthesis of monodisperse nanoprisms with a preselected edge length in the 30&#x2013;120 nm range simply by using one beam to turn off bimodal growth and the other (varied over the 450&#x2013;700 nm range) for controlling particle size.

Methods of controlling nanoparticle growth

This invention relates to methods for regenerating spent DNA detection chips for further use. Specifically, this invention relates to a method for removal of silver from used DNA detection chips that employ gold nanoparticle-oligonucleotide conjugate probes and that use silver staining for signal amplification.

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Evanston, IL, United States of America

Rongchao Jin