Abstract: A microfluidic controller and detector system and method for performing screening assays are disclosed. The microfluidic controller and detector system comprises a fluidic chip that includes at least two intersecting channels and a detection zone, a fluid direction system comprising an electrical interface configured for electrical contact with the at least two intersecting channels, an optics block having an objective lens disposed adjacent the detection zone, and a control system coupled to the optics block and adapted to receive and analyze data from the optics block. The electrical interface generally includes electrodes configured for electrical contact with the intersecting channels and coupled to electrode channels for supplying electrical input to the electrodes. A reference channel is optionally provided to calibrate the electrode channels.

Abstract: The present invention provides a method of assaying an enzyme-mediated coupling reaction between a first and a second reactant. The method includes contacting the first reactant with the second reactant in the presence of the enzyme. The second reactant includes a thiol derivative to yield a first product including a thiol derivative. The thiol derivative is then detected in the first product.

Abstract: The present invention provides a method of assaying an enzyme-mediated coupling reaction between a first and a second reactant. The method comprises contacting the first reactant with the second reactant in the presence of the enzyme. The second reactant comprises a thiol derivative to yield a first product comprising a thiol derivative. The thiol derivative is then detected in the first product.

Abstract: An analytical or preparatory system comprised as a base unit, an adapter, and a substrate. The adapter is attached to an attachment region on the base unit, and the substrate is attached to an attachment region on the adapter. The adapter permits the base unit to be interfaced with a wide variety of different substrates to perform chemical and biological analytical analyses and preparatory procedures.

Abstract: The present invention provides multi-layer microfluidic systems, by providing additional substrate layers, e.g., third, fourth, fifth and more substrate layers, mated with the typically described first and second layers. Microfabricated elements, e.g., grooves, wells and the like, are manufactured into the surfaces between the various substrate layers. These microfabricated elements define the various microfluidic aspects or structures of the overall device, e.g., channels, chambers and the like. In preferred aspects, a separate microscale channel network is provided between each of the substrate layers.

Abstract: The invention provides improved systems, devices, and methods for analyzing a large number of sample compounds contained in standard multi-well microtiter plates or other array structures. The multi-well plates travel along a conveyor system to a test station having a microfluidic device. At the test station, each plate is removed from the conveyor and the wells of the multi-well plate are sequentially aligned with an input port of the microfluidic device. After at least a portion of each sample has been input into the microfluidic channel system, the plate is returned to the conveyor system. Pre and/or post testing stations may be disposed along the conveyor system, and the use of an X-Y-Z robotic arm and novel plate support bracket allows each of the samples in the wells to be input into the microfluidic network through a probe affixed to a microfluidic chip.

Abstract: Microfluidic devices and systems that include keying, registration or indication elements that communicate a functionality of the microfluidic device to the instrumentation which is used in conjunction with these devices. Indicator elements include structural indicators, electrical indicators, optical indicators and chemical indicators. Different indicator elements are indicative of different functionalities, e.g., applications, new vs. used, and the like.

Abstract: Fluid introduction is facilitated through the use of a port which extends entirely through a microfluidic substrate. Capillary forces can be used to retain the fluid within the port, and a series of samples or other fluids may be introduced through a single port by sequentially blowing the fluid out through the substrate and replacing the removed fluid with an alternate fluid, or by displacing the fluid in part with additional fluid. In another aspect, microfluidic substrates have channels which varying in cross-sectional dimension so that capillary action spreads a fluid only within a limited portion of the channel network. In yet another aspect, the introduction ports may include a multiplicity of very small channels leading from the port to a fluid channel, so as to filter out particles or other contaminants which might otherwise block the channel at the junction between the channel and the introduction port.

Abstract: Electrokinetic devices having a computer for correcting for electrokinetic effects are provided. Methods of correcting for electrokinetic effects by establishing the velocity of reactants and products in a reaction in electrokinetic microfluidic devices are also provided. These microfluidic devices can have substrates with channels, depressions, and/or wells for moving, mixing and monitoring precise amounts of analyte fluids.

Abstract: The present invention provides novel microfluidic devices and methods for storing, reconstituting and accessing one or more library of assay components within library storage elements in a microfluidic device. In particular, the devices and methods of the invention are useful in screening large libraries of molecules.

Abstract: Apparatus and methods for modulating flow rates in microfluidic devices are provided. The methods involve modulating downstream pressure in the device to change the flow rate of materials in an upstream region of the device. Such methods include electrokinetic injection or withdrawal of materials through a side channel and the use of an absorbent material to induce wicking in the channel system. The apparatus provided includes a prefabricated wick in the device to provide for flow rate control. Additional methods for determining velocity of a particle and cell incubation time are also provided.

Abstract: Fluid introduction is facilitated through the use of a port which extends entirely through a microfluidic substrate. Capillary forces can be used to retain the fluid within the port, and a series of samples or other fluids may be introduced through a single port by sequentially blowing the fluid out through the substrate and replacing the removed fluid with an alternate fluid, or by displacing the fluid in part with additional fluid. In another aspect, microfluidic substrates have channels which varying in cross-sectional dimension so that capillary action spreads a fluid only within a limited portion of the channel network. In yet another aspect, the introduction ports may include a multiplicity of very small channels leading from the port to a fluid channel, so as to filter out particles or other contaminants which might otherwise block the channel at the junction between the channel and the introduction port.

Abstract: Microfluidic devices and systems having enhanced detection sensitivity, particularly for use in non-fluorogenic detection methods, e.g., absorbance. The systems typically employ planar microfluidic devices that include one or more channel networks that are parallel to the major plane of the device, e.g., the predominant plane of the planar structure, and a detection channel segment that is substantially orthogonal to that plane. The detection system is directed along the length of the detection channel segment using a detection orientation that is consistent with conventional microfluidic systems.

Abstract: Multiplexed microfluidic devices include a plurality of modular microfluidic elements, all of which are attached to a common frame or substrate, which itself includes one or more common input elements that are connected to corresponding input elements within several or each of the microfluidic modules for use in common control and/or common detection operations for each of the modules.

Abstract: The present invention provides microfluidic devices that comprise a body structure comprising at least a first microscale channel network disposed therein. The body structure has a plurality of ports disposed in the body structure, where each port is in fluid communication with one or more channels in the first channel network. The devices also include a cover layer comprising a plurality of apertures disposed through the cover layer. The cover layer is mated with the body structure whereby each of the apertures is aligned with a separate one of the plurality of ports.

Abstract: The present invention provides for techniques for transporting materials using electrokinetic forces through the channels of a microfluidic system. The subject materials are transported in regions of high ionic concentration, next to spacer material regions of high ionic concentration, which are separated by spacer material regions of low ionic concentration. Such arrangements allow the materials to remain localized for the transport transit time to avoid mixing of the materials. Using these techniques, an electropipettor which is compatible with the microfluidic system is created so that materials can be easily introduced into the microfluidic system. The present invention also compensates for electrophoretic bias as materials are transported through the channels of the microfluidic system by splitting a channel into portions with positive and negative surface charges and a third electrode between the two portions, or by diffusion of the electrophoresing materials after transport along a channel.

Abstract: The present invention provides novel microfluidic devices and methods that are useful for performing high-throughput screening assays. In particular, the devices and methods of the invention are useful in screening large numbers of different compounds for their effects on a variety of chemical, and preferably, biochemical systems.

Abstract: The present invention provides methods of electrophoretically separating macromolecular species, as well as compositions and systems useful in carrying out such methods. Specifically, the methods of the present invention comprise providing a substrate that has at least a first capillary channel disposed therein. The surface of the channel has a first surface charge associated therewith, and is filled with a water soluble surface adsorbing polymer solution that bears a net charge that is the same as the charge on the capillary surface.

Abstract: Microfluidic devices having predisposed assay components for increased throughput and prolonged shelf life are provided.

Abstract: A method of characterizing a polypeptide, comprising providing a first capillary channel having a separation buffer disposed within, wherein the separation buffer comprises a non-crosslinked polymer solution, a buffering agent, a detergent, and a lipophilic dye. The separation buffer is provided such that, at the time of detection, the detergent concentration in the buffer is not above the critical micelle concentration. The polypeptide is introduced into one end of the capillary channel. An electric field is applied across a length of the capillary channel, which transports polypeptides of different sizes through the polymer solution at different rates. The polypeptide is then detected as it passes a point along the length of the capillary channel.