Abstract: A comprehensive two-dimensional gas chromatograph, comprising a sample injector, a primary dimension column, a two-position three-way valve, a secondary dimension column, a three-way tube, a heating oven and a detector, wherein an inlet end(s) of the sample injector is connected to a carrier gas line and as well to a sample line, and an outlet end thereof is connected to a first end of the primary dimension column, a second end of the primary dimension column is connected to a first branch of the three-way tube, a second branch of the T-union is connected to a first end of the secondary dimension column, a second end of the secondary dimension column is connected to an inlet of the detector, a third branch of the three-way tube is connected to a gas inlet of the two-position three-way valve, and a first gas outlet of the two-position three-way valve is connected to the carrier gas line.

Abstract: A comprehensive two-dimensional gas chromatograph, comprising a sample injector, a primary dimension column, a two-position three-way valve, a secondary dimension column, a three-way tube, a heating oven and a detector, wherein an inlet end(s) of the sample injector is connected to a carrier gas line and as well to a sample line, and an outlet end thereof is connected to a first end of the primary dimension column, a second end of the primary dimension column is connected to a first branch of the three-way tube, a second branch of the T-union is connected to a first end of the secondary dimension column, a second end of the secondary dimension column is connected to an inlet of the detector, a third branch of the three-way tube is connected to a gas inlet of the two-position three-way valve, and a first gas outlet of the two-position three-way valve is connected to the carrier gas line.

Abstract: A comprehensive two-dimensional gas chromatography system comprising of a sample inlet, a primary dimension column, a secondary dimension column, a thermal modulator, and a detector. The thermal modulator has a first modulation position and a second modulation position. The sample inlet connects to the primary dimension column. The exit of the primary dimension column connects to the first modulation position via a fluidic path, the first modulation position connects to the second modulation position via a fluidic path, the second modulation position connects to the secondary dimension column via a fluidic path, and the exit of the secondary dimension column connects to the detector. The fluidic path between the exit of the primary dimension column and the inlet of the secondary dimension column is a modulation column.

Abstract: The present invention provides a device for handling fluids, and more particularly a merging apparatus for fluidic and microfluidic devices utilizing passive valving in conjunction with a single sensor to uniformly blend contributory working fluid streams. Symmetric and non symmetric embodiments with and without branch channels are described. The present invention also provides methods for merging liquids using the device of the invention.

Abstract: A device for providing a constant mass flow rate to a downstream column system of a gas chromatograph includes a small full scale mass flow controller that controls carrier gas to flow at a first mass flow rate and a flow resistance element, including an inlet port connected to a sample inlet, an outlet port connected to the downstream column system, and a pressure sensing port in fluid communication with the outlet port and the mass flow controller. A sample inlet pressure controller controls the sample inlet at a first pressure, and a pressure sensor measures a second pressure of the carrier gas at the pressure sensing port. A set point of the first pressure is determined as a function of the second pressure, flow resistance of the flow resistance element, and a second mass flow rate from the inlet port to the outlet port of the flow resistance element.

Abstract: A thermal modulation device for a gas chromatography (GC) system a cold zone, a first hot zone and a second hot zone, which are located outside of a GC oven of the GC system, and a flexible capillary column. The cold zone includes a thermoelectric cooler assembly. The first hot zone is adjacent a first side of the cold zone, and has a corresponding first heat source. The second hot zone is adjacent a second side of the cold zone, and has a corresponding second heat source. The flexible capillary column includes a first segment, configured to move between the first hot zone and the cold zone in accordance with a modulation frequency, and a second segment, configured to move between the cold zone and the second hot zone in accordance with the modulation frequency.

Abstract: The present invention relates to a wicking inhibitor for fluidic and microfluidic devices that reduces wicking by providing a structure that interrupts the flow of a working fluid through a fluidic channel interface having corner angles greater than ninety degrees.

Abstract: A device for providing a constant mass flow rate to a downstream column system of a gas chromatograph includes a small full scale mass flow controller that controls carrier gas to flow at a first mass flow rate and a flow resistance element, including an inlet port connected to a sample inlet, an outlet port connected to the downstream column system, and a pressure sensing port in fluid communication with the outlet port and the mass flow controller. A sample inlet pressure controller controls the sample inlet at a first pressure, and a pressure sensor measures a second pressure of the carrier gas at the pressure sensing port. A set point of the first pressure is determined as a function of the second pressure, flow resistance of the flow resistance element, and a second mass flow rate from the inlet port to the outlet port of the flow resistance element.

Abstract: A thermal modulation device for a gas chromatography (GC) system a cold zone, a first hot zone and a second hot zone, which are located outside of a GC oven of the GC system, and a flexible capillary column. The cold zone includes a thermoelectric cooler assembly. The first hot zone is adjacent a first side of the cold zone, and has a corresponding first heat source. The second hot zone is adjacent a second side of the cold zone, and has a corresponding second heat source. The flexible capillary column includes a first segment, configured to move between the first hot zone and the cold zone in accordance with a modulation frequency, and a second segment, configured to move between the cold zone and the second hot zone in accordance with the modulation frequency.

Abstract: The invention is directed to microfluidic devices comprising at least two processing channels, wherein each of the processing channels comprises an inlet, an outlet, and a high-flow-resistant and hydrophilic conduit; a distributing channel, wherein the distributing channel comprises an upstream end and a downstream end, and is in fluid communication with each inlet of the processing channels via the high-flow-resistant and hydrophilic conduit; and a flushing channel, wherein the flushing channel comprises an upstream end and a downstream end, and is in fluid communication with each outlet of the processing channels. The invention also provides methods of using the microfluidic devices.

Abstract: The invention is directed to microfluidic devices comprising at least two processing channels, wherein each of the processing channels comprises an inlet, an outlet, and a high-flow-resistant and hydrophilic conduit; a distributing channel, wherein the distributing channel comprises an upstream end and a downstream end, and is in fluid communication with each inlet of the processing channels via the high-flow-resistant and hydrophilic conduit; and a flushing channel, wherein the flushing channel comprises an upstream end and a downstream end, and is in fluid communication with each outlet of the processing channels. The invention also provides methods of using the microfluidic devices.

Abstract: The present invention provides a device for handling fluids, and more particularly a merging apparatus for fluidic and microfluidic devices utilizing passive valving in conjunction with a single sensor to uniformly blend contributory working fluid streams. Symmetric and non symmetric embodiments with and without branch channels are described. The present invention also provides methods for merging liquids using the device of the invention.

Abstract: An wicking inhibitor for fluidic and microfluidic devices reduces wicking by providing a structure that interrupts the flow of a working fluid through a fluidic channel interface having corner angles greater than ninety degrees.

Abstract: An bubble-resistant injector port for fluidic and microfluidic devices includes an air-exhaustion feature to reduce the inclusion of bubbles or voids in injected samples, particularly in samples injected by a micropipette. The air-exhaustion feature comprises an air-exhaustion cavity in gas communication with the injector port through a narrowed channel that permits a flow of air into the cavity, while impeding a flow of injected liquid into the cavity.

Abstract: Methods and devices for controlling temperature by precise heating without the need of using a temperature sensor are provided. The device comprises a resistive heating element (6), a controller (3), a heating circuit and a temperature sensing circuit. The temperature of the resistive heating element can be determined based on the resistance of the resistive heating element (6), which changes monotonically with its temperature. The resistive heating element (6) thus serves both as a heating element and as a temperature sensor, thereby obviating the need for a separate temperature sensor.