USA As Represented by Secretary of the Navy

Government of the United States of America, As Represented by the Secretary of Commerce

Peter B Howell, Jr

Frances S Ligler

David R Mott

Stephanie Fertig

Aron Bobrowski

Joel P Golden

David Judson Ross

Wyatt N Vreeland

Daniel A Ateya

Adam R Shields

Richard Eitel

A sheath flow system having a channel with at least one fluid transporting structure located in the top and bottom surfaces situated so as to transport the sheath fluid laterally across the channel to provide sheath fluid fully surrounding the core solution. At the point of introduction into the channel, the sheath fluid and core solutions flow side by side within the channel or the core solution may be bounded on either side by the sheath fluid. The system is functional over a broad channel size range and with liquids of high or low viscosity. The design can be readily incorporated into microfluidic chips without the need for special manufacturing protocols. Uses include extruding materials and/or fabricating structures.

Sheath flow methods for fabricating structures

Sheath flow methods

A sheath flow system having a channel with first and second fluid transporting structures located on opposing surfaces facing one another across the channel in the top and bottom surfaces of the channel situated so as to transport the sheath fluid laterally across the channel to provide sheath fluid fully surrounding the core solution. At the point of introduction into the channel, the sheath fluid and core solutions flow side by side within the channel or the core solution may be bounded on either side by the sheath fluid. The system is functional over a broad channel size range and with liquids of high or low viscosity. The design can be readily incorporated into microfluidic chips without the need for special manufacturing protocols.

Sheath flow apparatus for laminar flow systems

A magnetic bead trap-and-mixer includes a channel having openings at opposing ends, and a rotor adjacent to the channel and comprising a permanent magnet, wherein the rotor is adapted to apply a magnetic field to the channel of sufficient strength to direct the movement of magnetic beads therein. In aspects, the channel is straight and/or has narrowed end. In further aspects, the rotor generates in the channel areas of areas of strong magnetic fields alternating with areas of very weak magnetic fields and the strong magnetic fields extend entirely across the channel.

Rotationally actuated magnetic bead trap and mixer

A device having: a laminar flow channel for liquids; two or more electrodes; a confining fluid inlet; a sample inlet; and a meter for measuring the impedance of any fluid between the electrodes. The device may have one or more specific binding sites, or it may have sheathing and unsheathing fluid transporting structures. A method of: providing the device; flowing a confining fluid and a conductive liquid that may contain cells or particles through the channel as described herein; and measuring the impedance between the electrodes.

Electrical detection using confined fluids

A sheath flow system having a channel with at least one fluid transporting structure located in the top and bottom surfaces situated so as to transport the sheath fluid laterally across the channel to provide sheath fluid fully surrounding the core solution. At the point of introduction into the channel, the sheath fluid and core solutions flow side by side within the channel or the core solution may be bounded on either side by the sheath fluid. The system is functional over a broad channel size range and with liquids of high or low viscosity. The design can be readily incorporated into microfluidic chips without the need for special manufacturing protocols.

Sheath flow device and method

Flow step focusing isolates and concentrates a molecule of interest by flowing a liquid comprising a molecule of interest through a main channel having an inlet and an outlet with application of a first pressure at the inlet; applying a voltage along the channel during the flowing, wherein the voltage is configured to have a polarity such that it drives the molecule of interest in a direction opposite the flow of the liquid; controlling the first pressure and/or the voltage in a manner so as to trap and concentrate the molecule of interest in a region of the main channel; and removing the concentrated molecule of interest from the channel by recovering a portion of the liquid from a side channel diverging from the main channel, wherein the side channel is maintained at a pressure lower than the first pressure. Also disclosed is an apparatus for such.

Flow step focusing

A computational 'toolbox' can be used for the a priori design of optimized fluidic components. These components include a channel under low-Reynolds number, pressure-driven flow, with an arrangement of grooves cut into the top and/or bottom to generate a tailored cross-channel flow. An advection map for each feature (i.e., groove of a particular shape and orientation) predicts the lateral transport of fluid within the channel due to that feature. Applying the advection maps in sequence generates a representation of the outflow distribution for complex designs that combine one or more features. Therefore, the effect of the complex three-dimensional flow field can be predicted without solving the governing flow equations through the composite geometry, and the resulting distribution of fluids in the channel is used to evaluate how well a component performs a specified task. The toolbox is applied to determine optimal combinations of features for specified mixer sizes and mixing metrics.

Numerical toolbox for design of fluidic components and systems

A sheath flow system having a channel with at least one fluid transporting structure located in the top and bottom surfaces situated so as to transport the sheath fluid laterally across the channel to provide sheath fluid fully surrounding the core solution. At the point of introduction into the channel, the sheath fluid and core solutions flow side by side within the channel or the core solution may be bounded on either side by the sheath fluid. The system is functional over a broad channel size range and with liquids of high or low viscosity. A wide variety of shapes of fibers and other materials can be produced from this system through the use of polymerizable material.

Sheath flow device

A method and device are provided for affinity gradient focusing for directing at least one analyte in a solution containing a pseudostationary phase and located in a channel such as a capillary or a microchannel. The method includes establishing a steady-state spatial gradient in a retention factor of the pseudostationary phase for the at least one analyte. The analyte is caused to be moved within the channel whereby the concentration of the at least one analyte changes at one or more positions along the gradient. The pseudostationary phase is charged and the analyte is either neutral or charged or alternatively, the pseudostationary phase is neutral and the analyte is charged. The device may include a fluid channel, a pseudostationary phase having a retention factor gradient, an electrical current source and a pump system for establishing the bulk flow in the solution in the channel.

Growing community of inventors

Gaithersburg, MD, United States of America

Peter B Howell, Jr