Wisconsin Alumni Research Foundation

Mattson Instruments, Inc.

Other

Gwc Technologies, Inc.

Stephen C Weibel

Robert M Corn

David R Mattson

Lloyd M Smith

Robert John Hamers

Michael Robert Shortreed

Joel P Covey

Scott A Callaghan

Matthew R Lockett

Randolph W Bach

Michael J Green

Bin Sun

Tony G Frutos

SPR-compatible substrates for high density microarray fabrication and analyses are provided. Novel carbon-on-metal thin film substrate architecture permits the integration of surface plasmon resonance detection with photolithographically fabricated biomolecule arrays for the analysis of biomolecular interactions. The utility of the technology is shown in the analysis of specific DNA-DNA, DNA-RNA and DNA-protein binding interactions. These new substrates may be used to determine the secondary structure of RNA molecules, to probe the sequence-specific binding kinetics and affinity of proteins and small molecules, and as substrates for small-molecule combinatorial chemistry platforms for drug discovery applications.

Surface plasmon resonance compatible carbon thin films

Disclosed is a horizontal SPR sensor apparatus that provides a simplified beam path, ease of sample handling with concomitant ease of analysis. The horizontal SPR device disclosed herein includes an input and output transfer mirror pair that translates vertically along an axis perpendicular to the beam path. The invention includes an input/output scanner mirror pair that is operatively linked to the transfer mirror pair. This allows for rotation of the scanner mirror pair in response to the vertical translation of the transfer mirror pair and maintains the incident light focus on the metal film/sample layer while varying the angle of incidence and thereby exciting the surface plasmon resonance at the thin metal film layer. Further, this allows the detector and detector optics to be fixed providing for the implementation of heavier multi-stage cooled detectors. Finally, the invention provides an SPR device having a smaller footprint than known alternatives.

Horizontal surface plasmon resonance sensor apparatus

Adsorption of molecules onto a thin metallic surface such as of gold, silver or copper is measured by surface plasmon resonance (SPR) using Fourier Transform (FT) spectroscopy. Reflectance spectra from a prism/metallic film sample surface at a fixed angle of incidence is measured with FT spectroscopy. The reflectance spectrum exhibits a pronounced minimum due to the SPR effect, which can be shifted by changing the angle of incidence or metallic film thickness. The position of the reflectance minimum shifts in wavelength with the adsorption of molecules onto the gold surface due to a change in the index of refraction at the interface. The FT-SPR sensor instrument provides wavelength stability and reproducibility of the resonance wavelength to permit detection of small wavelength shifts, and also substantially increases the spectral range over which the SPR measurements can be made. A beam of broadband radiation from a Michelson interferometer is directed through an SPR sample cell and onto a detector where the output signal is processed using standard FT techniques.

Fourier transform surface plasmon resonance adsorption sensor instrument

A Michelson interferometer includes a beamsplitter onto which an input light beam is directed. The beamsplitter divides the input light beam into a first beam portion incident upon a first fixed reflector and a second beam portion incident upon a movable retroreflector. The movable retroreflector reflects the second beam onto another fixed reflector and then back to the beamsplitter where the first and second beams are combined and directed to a detector. The movable retroreflector is attached to one end of a rotating arm moving at a constant angular velocity. The retroreflector reflects the second beam at a fixed location in its orbital path. The angular velocity of the retroreflector and rotating arm combination may be varied over a wide range to provide a large modulated frequency bandwidth. The operating duty cycle of the interferometer may be doubled by attaching a second retroreflector to the other end of the rotating arm, with the weights of the two retroreflectors counterbalancing each other. The interferometer's optical alignment is insensitive to angular tilt and lateral shear (horizontal and vertical translation) of the interferometer's scanning element.

Michelson interferometer with orbiting retroreflector

An interferometer including a beamsplitter and fixed and movable cube corner reflectors is adapted for use in a Fourier-transform infrared (FTIR) spectrometer. The spectrometer includes a cast metal base, such as of aluminum, with the interferometer including an IR source housing formed integrally with the base for dissipating heat via conduction. The IR source housing is hollow and open at the top for receiving a removable opaque printed circuit board (PCB) which is coupled to and provides support for and electrical current to an IR source within the housing. The housing includes two apertures in lateral portions thereof. An IR beam is directed by the source through a first aperture to the Michelson interferometer, while a second aperture is adapted to receive a fiber optic light guide to allow for direct viewing of the IR source in a safe manner without removing the PCB cover of the housing. An interferometer chamber is isolated from a sample chamber, both of which chambers may be independently purged and are further isolated from the spectrometer's electronic circuitry. The spectrometer includes a minimum number of reflectors outside of the interferometer for reduced light loss and improved signal-to-noise ratio with the interferometer providing an output IR beam to a first focus mirror which horizontally focuses the beam on and directs the beam through the sample and thence onto a second focus mirror which vertically focuses the beam on a closely spaced IR detector integrated in a printed circuit board.

Spectrometer and IR source therefor

A dual beam Fourier transform spectrometer produces two beams from a single infrared (IR) source. The beams are directed through a sample region, with one beam transiting a sample and the other beam transiting a reference cell. The sample and reference beams are then directed to a Michelson interferometer with cube corner retroflectors for optically cancelling the background signal from the separate sample and reference beams and for optically combining the sample and reference beams in an optically accurate and stable manner. The single combined beam, which contains the difference interferogram is directed to a single detector.

Growing community of inventors

Madison, WI, United States of America

Stephen C Weibel