University of Illinois

Sru Biosystems, Inc.

X-body, Inc.

Meng Lu

Brian T Cunningham

J Gary Eden

Sung-Jin Park

Anusha Pokhriyal

Stephen C Schulz

Chun Ge

Stephen C Shulz

Sherine George

Vikram Chaudhery

A label-free biosensor detection arrangement incorporating an external cavity laser (ECL) includes a tunable lasing element (e.g. an antireflection coated laser diode or semiconductor optical amplifier) and a narrow bandwidth resonant reflectance filter as the wavelength-selective element for the tunable lasing element. A sample is deposited on the surface of the resonant reflectance filter containing a biological material. The wavelength emitted by the external cavity laser is continuously tunable by binding interactions between the biological material and the resonant reflectance filter or adsorption of the biological material present in the sample on resonant reflectance filter. The narrow bandwidth resonance reflectance filter can take the form of photonic crystal (PC), a Bragg stack, or a Brag fiber reflection filter.

External cavity laser biosensor arrangements

A silicon-based photonic crystal includes a silicon substrate, a first dielectric with a grating structure formed therein, and a second dielectric with a higher index of refraction that covers at least a portion of the grating structure. The first dielectric can be formed on the silicon substrate, or a Fabry-Perot optical cavity can be formed between the silicon substrate and the first dielectric. An instrument can excite a fluorophore coupled to the photonic crystal by focusing collimated incident light that includes the fluorophore's excitation wavelength to a focal line on the surface of the photonic crystal such that the focal line is substantially parallel to the grating direction and can detect fluorescence radiation emitted by the fluorophore in response to the incident light. To provide for fluorescence enhancement, the excitation wavelength and/or emission wavelength of the fluorophore can couple to an optical resonance of the photonic crystal.

Silicon-based photonic crystal fluorescence enhancement and laser line scanning instrument

A method of forming a microplasma device places a curable polymer material between a mold having a negative volume impression of microcavities and/or microchannels and a substrate. The polymer is cured and then the mold is separated from the solid polymer. The method can form a microplasma device that includes a substrate and either or both of a microchannel or microcavity defined in a polymer layer supported by the substrate. Electrodes arranged with respect to the polymer material can excite plasma in a discharge medium contained in the microchannel or the microcavity or both. A flexible mold is preferably used to fabricate transparent polymer microcavities onto rigid substrates. A rigid mold is preferably used to fabricate transparent polymer microcavities onto flexible substrates. Having one of the mold and the substrate flexible and the other rigid aids in the separation of the mold from the cured polymer.

Polymer microcavity and microchannel device and array fabrication method

A microplasma device includes a substrate and either or both of a microchannel or microcavity defined in a polymer layer supported by the substrate. Electrodes arranged with respect to the polymer material can excite a plasma in a discharge medium contained in the microchannel or the microcavity or both. A method of forming a microplasma device places a curable polymer material between a mold having a negative volume impression of microcavities and/or microchannels and a substrate. The polymer is cured and then the mold is separated from the solid polymer.

Polymer microcavity and microchannel devices and fabrication method

A photonic crystal substrate exhibiting resonant enhancement of multiple fluorophores has been demonstrated. The device, which can be fabricated uniformly from plastic materials over a &#x2dc;3&#xd7;5 insurface area by nanoreplica molding, features a 1-D periodic grating structure which utilizes two distinct resonant modes to enhance electric field stimulation of a first dye excited by a first laser (e.g., &#x3bb;=632.8 nm laser exciting cyanine-5) and a second dye excited by a second laser (e.g., &#x3bb;=532 nm laser exciting cyanine-3). The first and second lasers could be replaced by a single variable wavelength (tunable) laser. Resonant coupling of the laser excitation to the photonic crystal surface is obtained for each wavelength at a distinct incident angle &#x3b8;. The photonic crystal is capable of amplifying the output of any fluorescent dye with an excitation wavelength in a given wavelength range (e.g., the range 532 nm&#x3c;&#x3bb;&#x3c;660 nm) by selection of an appropriate incident angle. The device can be used for biological assays that utilize multiple fluorescent dyes within a single imaged area, such as gene expression microarrays.

Multi-color fluorescence enhancement from a photonic crystal surface

A biosensor based upon a vertically emitting, distributed feedback (DFB) laser is disclosed. In one configuration, the DFB laser comprises a replica-molded, one- or two-dimensional dielectric grating coated with a laser dye-doped-polymer as the gain medium. A sensor is also described in which the grating layer and the active layer are combined into a single layer. DFB lasers using an inorganic or organic thin film with alternating regions of high and low index of refraction as the active layer are also disclosed. The sensor actively generates its own narrowband high intensity light output without stringent requirements for coupling alignment, thereby resulting in a simple, robust illumination and detection configuration.

Growing community of inventors

Champaign, IL, United States of America

Meng Lu