The Penn State Research Foundation

Northwestern University

Akzo Nobel N.v.

Michael J Natan

Ralph Franklin

William J Parr

Anthony J Castro

Richard P Van Duyne

Christine D Keating

Bonnie E Baker

Robert J Bianchini

King C Sheng

A biosensor based on complexes between biomolecule receptors and colloidal Au nanoparticles, and more specifically, colloid layers of receptor/Au complexes that can be used to detect biomolecule analytes through measuring of binding-induced changes in electrical resistance or surface plasmon resonance. Also disclosed is a method for detecting and analysing carrier-borne chemical compounds with Raman spectroscopy using an improved SERS substrate. Further disclosed is an improved method for detecting compounds in solvents using capillary electrophoresis in conjunction with Raman spectroscopy.

Self-assembled metal colloid monolayers having size and density gradients

A substrate for surface enhanced Raman scattering (SERS) is described in which the analyte is deliberately sandwiched between a colloidal metal nanoparticle and the SERS substrate. In a first embodiment, the analyte is a protein, and the sandwich comprises a protein:Au colloid complex adsorbed to an aggregated Ag sol. Another embodiment concerns a protein:Ag complex, adsorbed to an aggregated Ag sol. In another embodiment, a protein:Au colloid complex is covalently or non-covalently attached to a macroscopic SERS-active substrate. In yet another embodiment, the colloidal nanoparticle is stabilized by a polymeric additive. In yet another embodiment, detection is accomplished at extremely low analyte concentrations. In a final embodiment, control of analyte orientation with respect to the SERS substrate is demonstrated.

Surface enhanced raman scattering from metal nanoparticle-analyte-noble

Self-assembled metal colloid monolayers and detection methods therewith

What follows is a description of an invention for the preparation of macroscopic metal surfaces by self assembly of colloidal metal particles. Metal surfaces play a critical role in technology, and in many cases, the surface morphology dictates function. The strategy delineated herein, the use of nanometer scale colloidal particles to form two-dimensional arrays, allows control of surface morphology to a degree previously unattainable and perhaps even unimaginable. Specific applications for metallic surfaces with controlled nanostructure include: (i) surface enhanced Raman scattering and all surface spectroscopies based on roughened metal surfaces, including second harmonic generation, surface enhanced hyperRaman scattering, surface plasmon resonance, and surface plasmonpolariton resonance; (ii) biocompatible surfaces, including those that comprise the working elements of electrochemical biosensors, substrates for matrix-assisted laser desorption ionization (MALDI) and biocompatible materials such as implants; (iii) catalysis; (iv) non-linear optical devices, including those based on second or third harmonic generation, the optical Kerr effect, etc.; and (v) electrochemical applications, including those requiring very high surface area/geometric area ratios, arrays of closely or variably spaced microelectrode arrays, and surfaces with exceptional biocompatibility and facile electron transfer properties.

Self-assembled metal colloid monolayers

A method for providing a conductive metal deposit on the surface of a dielectric substrate by applying a composition comprising a mixture of a salt and amine or amide compound to the substrate and subjecting the composition to a continuous wavelength laser beam.

Laser direct writing

Growing community of inventors

State College, PA, United States of America

Michael J Natan