Abstract: The present invention relates to a device for interfacing nanofluidic and microfluidic components suitable for use in performing high throughput macromolecular analysis. Diffraction gradient lithography (DGL) is used to form a gradient interface between a microfluidic area and a nanofluidic area. The gradient interface area reduces the local entropic barrier to nanochannels formed in the nanofluidic area. In one embodiment, the gradient interface area is formed of lateral spatial gradient structures for narrowing the cross section of a value from the micron to the nanometer length scale. In another embodiment, the gradient interface area is formed of a vertical sloped gradient structure. Additionally, the gradient structure can provide both a lateral and vertical gradient.

Abstract: Methods and apparatus for sorting microstructures, such as macromolecules, viruses, cells, and minute particles, in a fluid using microlithographic sorting array that is reversibly sealed by a cover. A silicone elastomer cover is used in one embodiment. In another, silicon microstructures are used to case elastomeric replicas of obstacle arrays, the tops of which reversibly seal against a flat surface. The reversible seal allows access to fractionated microstructures within the structure for further analysis.

Abstract: A device for the integrated micromanipulation, amplification, and analysis of polyelectrolytes such as DNA comprises a microchip which contains electrodes for dielectrophoresis powered by an AC signal generator, and a trapping electrode attached to a direct current source that can be heated to specific temperatures. Nucleic acids can be heated and cooled to allow for denaturation, the annealing of complementary primers and enzymatic reactions, as in a thermocycling reaction. After such a reaction has been completed on the trapping electrode, the dielectrophoretic field can be switched to a direct current to release the product and direct it through a matrix for fractionation and/or analysis. The device includes data analysis equipment for the control of these operations, and imaging equipment for the analysis of the products. The invention permits the efficient handling of minute samples in large numbers, since reactions occur while sample material is positioned on an electrode in a microfluidic channel.

Abstract: A sorting apparatus and method for fractionating and simultaneously viewing individual microstructures, such as free cells, viruses, macromolecules, or minute particles in a fluid medium. The sorting apparatus is composed of a substrate having a receptacle located therein, the receptacle having sidewalls and a floor. An array of obstacles is positioned within the receptacle with the obstacles upstanding from the floor of the receptacle. A transparent cover overlies the array of obstacles to cover the receptacle and afford visual observation of migration of the microstructures exclusively through the array of obstacles. Electrodes may be positioned within the receptacle to generate an electric field in the fluid medium in the receptacle in order to induce the migration of the microstructures. Migration of the microstructures may also occur, for example, by a hydrodynamic field, an optical field, a magnetic field, or a gravity field applied to the receptacle.

Abstract: A sorting apparatus and method for fractionating and simultaneously viewing individual microstructures, such as free cells, viruses, macromolecules, or minute particles in a fluid medium. The sorting apparatus is composed of a substrate having a receptacle located therein, the receptacle having sidewalls and a floor. An array of obstacles is positioned within the receptacle with the obstacles upstanding from the floor of the receptacle. A transparent cover overlies the array of obstacles to cover the receptacle and afford visual observation of migration of the microstructures exclusively through the array of obstacles. Electrodes may be positioned within the receptacle to generate an electric field in the fluid medium in the receptacle in order to induce the migration of the microstructures. Migration of the microstructures may also occur, for example, by a hydrodynamic field, an optical field, a magnetic field, or a gravity field applied to the receptacle.