Abstract: Methods and devices for reducing evaporation of sample materials from the wells of multiwell plates are disclosed which find particular utility when the plates are placed in a stacked configuration. An example of the methods includes providing at least a first multiwell plate which is configured to be placed in a stacked configuration with at least one second multiwell plate, the at least first multiwell plate having a plurality of wells for receiving sample material therein and opposing side walls which extend around the plate and which define a ridge spaced inwardly of the side walls and extending around the plate between the side walls and the plurality of wells, the method including at least partially filling the ridge with a liquid such as water or buffer solution. The ridge can include one or more ribs which extend upwardly from a lower surface of the ridge to help reduce sloshing of the liquid contained within the ridge and to add structural strength and rigidity to the multiwell plate.

Abstract: Methods and systems that employ hybrid fluid flow profiles for optimized movement of materials through channel networks. These systems employ hybrid pressure-based and electrokinetic based flow systems for moving materials through interconnected channel networks while maintaining interconnection among the various channel segments. In particular, the invention is generally directed to channel networks where flow in a first channel segment is driven by pressure flow with its consequent parabolic flow profile, while flow in an interconnected channel segment is dominated by electrokinetic flow with its consequent plug flow profile. The invention also provides channel networks wherein fluid flow in channel segments is driven by both pressure and electric field and the multiple species contained in a fluid plug are separated by altering the applied pressure and electric fields in the various channel segments of the channel networks.

Abstract: This invention provides systems and methods of running multiple different analyses on a microfluidic device.

Abstract: Integrated systems, apparatus, software, and methods for performing biochemical analysis, including DNA sequencing, genomic screening, purification of nucleic acids and other biological components and drug screening are provided. Microfluidic devices, systems and methods for using these devices and systems for performing a wide variety of fluid operations are provided. The devices and systems of are used in performing fluid operations which require a large number of iterative, successive or parallel fluid manipulations, in a microscale, or sealed and readily automated format.

Abstract: The present invention is directed to a method for determining the molecular weight and diffusivity of a sample solute by providing a plus shaped microchannel network on a microfluidic chip, having at least four microchannels intersecting at a cross point; flowing a sample stream comprising a sample solute of unknown diffusivity and a blank stream from separate microchannels through the cross point and out to separate microchannels; creating a sample curve measuring the concentration of the sample solute that diffuses from the sample stream to the blank stream at the cross point while altering the flowrate of one of the blank stream or the sample stream; and determining a diffusion coefficient of the sample solute by extrapolating data from similar curves of at least two solutes having known molecular weights and/or diffusion coefficients created under similar conditions as those generated by the sample solute.

Abstract: Methods and systems for use in separating sample materials into different fractions employing pressure-based fluid flow for simultaneous loading of a sample and a reagent into a sample loading channel of a microfluidic device. The sample is loaded from an external source through an attached external sampling capillary. The reagent, which may be a molecular weight standard, a diluent, a detergent, or a labeling reagent, is loaded from a reservoir integral to the microfluidic device via a reagent introduction channel within the device. The sample and reagent form a mixture in the sample loading channel. A portion of the mixture is electrokinetically injected from the sample loading channel, via an injection channel, into a separation channel, where it is separated electrophoretically.

Abstract: The present invention provides novel microfluidic devices and methods for performing pulsed field mobility shift assays in microfluidic devices. In particular the devices and methods of the invention utilize differences between electrophoretic mobilities (e.g., as between reactants and products, especially in non-fluorogenic reactions) in order to separate the species and thus analyze the reaction.

Abstract: Microfluidic devices and systems for affecting the serial to parallel conversion of materials introduced into the device or system. Material or materials to be converted from a serial orientation, e.g., a single channel, into a parallel orientation, e.g., multiple channels, are introduced into an open chamber or field in which containing flows of materials maintain the cohesiveness of the sample material plugs serially introduced into the open chamber. The sample material or materials are then redirected in the chamber toward and into a plurality of parallel channels that also communicate with the chamber.

Abstract: Methods and devices for reducing evaporation of sample materials from the wells of multiwell plates are disclosed which find particular utility when the plates are placed in a stacked configuration. An example of the methods includes providing at least a first multiwell plate which is configured to be placed in a stacked configuration with at least one second multiwell plate, the at least first multiwell plate having a plurality of wells for receiving sample material therein and opposing side walls which extend around the plate and which define a ridge spaced inwardly of the side walls and extending around the plate between the side walls and the plurality of wells, the method including at least partially filling the ridge with a liquid such as water or buffer solution. The ridge can include one or more ribs which extend upwardly from a lower surface of the ridge to help reduce sloshing of the liquid contained within the ridge and to add structural strength and rigidity to the multiwell plate.

Abstract: An electrode alignment apparatus may be used with a microfluidic device for accurate and repeatable alignment of electrode pins with reservoirs on the microfluidic device. The apparatus includes a base unit and an electrode block assembly that are moveable with respect to each other from an open position to a closed position. The electrode block assembly includes an interface array that is coupled to an interface array platform such that the interface array is moveable with respect to the interface array platform in three dimensions.

Abstract: A method to achieve controlled conductivity in microfluidic devices, and a device formed thereby. The method comprises forming a microchannel or a well in an insulating material, and ion implanting at least one region of the insulating material at or adjacent the microchannel or well to increase conductivity of the region.

Abstract: Methods and devices for delivering fluids into microfluidic device body structures are described. The methods and devices include the use of fluid manifolds which are integrated or interchangeable with device body structures. Methods of fabricating manifolds are also provided.

Abstract: A method to achieve controlled conductivity in microfluidic devices, and a device formed thereby. The method comprises forming a microchannel or a well in an insulating material, and ion implanting at least one region of the insulating material at or adjacent the microchannel or well to increase conductivity of the region.

Abstract: Improved microfluidic devices, systems, and methods allow selective transportation of fluids within microfluidic channels of a microfluidic network by applying, controlling, and varying pressures at a plurality of reservoirs. Modeling the microfluidic network as a series of nodes connected together by channel segments and determining the flow resistance characteristics of the channel segments may allow calculation of fluid flows through the channel segments resulting from a given pressure configuration at the reservoirs. To effect a desired flow within a particular channel or series of channels, reservoir pressures may be identified using the network model. Viscometers or other flow sensors may measure flow characteristics within the channels, and the measured flow characteristics can be used to calculate pressures to generate a desired flow. Multi-reservoir pressure modulator and pressure controller systems can optionally be used in conjunction with electrokinetic or other fluid transport mechanisms.

Abstract: The present invention provides novel methods and devices that employ microfluidic technology to generate molecular melt curves. In particular, the devices and methods in accordance with the invention are useful in providing for the analysis of PCR amplification products.

Abstract: Devices, systems and methods for use in separating sample materials into different fractions that employ bulk fluid flow for loading of samples followed by electrophoretic separation of the sample material. Devices employ configurations that optionally allow bulk sample loading with some or no displacement of a separation matrix within a separation conduit. Methods of using these devices, and systems that incorporate these devices are also envisioned.

Abstract: The present invention provides novel methods and devices for testing/verifying the configuration of one or more microfluidic elements in a microfluidic device. In particular the methods and devices of the invention are useful in testing for blockages or the presence of air bubbles in microfluidic elements.

Abstract: Methods and systems that employ hybrid fluid flow profiles for optimized movement of materials through channel networks. These systems employ hybrid pressure-based and electrokinetic based flow systems for moving materials through interconnected channel networks while maintaining interconnection among the various channel segments. In particular, the invention is generally directed to channel networks where flow in a first channel segment is driven by pressure flow with its consequent parabolic flow profile, while flow in an interconnected channel segment is dominated by electrokinetic flow with its consequent plug flow profile. The invention also provides channel networks wherein fluid flow in channel segments is driven by both pressure and electric field and the multiple species contained in a fluid plug are separated by altering the applied pressure and electric fields in the various channel segments of the channel networks.

Abstract: Multiphasic microfluidic apparatus for performing product fluid manipulation and separation in a single continuous unit are provided. Related methods, kits, and compositions are also provided.

Abstract: In a method for performing a hot start polymerase chain reaction, a reaction mixture including a primer, a template molecule, and a buffer—but no polymerase enzyme—is loaded in a reaction channel of a microfluidic device. An electrical current is applied to heat the reaction channel. A polymerase enzyme is delivered into the reaction channel, and the reaction channel is subjected to conditions such that the hot start polymerase chain reaction is performed. In a method for performing a temperature mediated reaction, a first component of the temperature mediated reaction is loaded in a reaction channel of a microfluidic device. An electrical current is applied to heat the reaction channel. A second component of the temperature mediated reaction is delivered into the reaction channel, and the reaction channel is subjected to conditions such that the temperature mediated reaction is performed.