Abstract: The present invention generally provides methods and systems for monitoring and controlling electroosmotic flow rates in microfluidic systems. Generally, such methods and systems monitor flow rates in electroosmotically driven microfluidic systems by flowing signaling elements within these channels and measuring the flow rate of these signals. The methods of monitoring flow rates are also applied to methods and systems for continuously monitoring and controlling these flow rates in electroosmotically driven microfluidic systems.

Abstract: Methods of detecting a component of interest, such as a protein, in a microfluidic system are provided. The methods include the use of a component-binding moiety specific to the component of interest, such as an antibody, to detect the component of interest. Also included are microfluidic devices and integrated systems for performing such assays, including devices utilizing flowable or fixed particle sets.

Abstract: Methods, systems, kits, and apparatus for calculating kinetic and concentration information in microscale systems are provided. Dwell times for access by a microfluidic system are varied and the resulting modulation of signal profile information used to provide a first order estimation of an activity of a potential activity modulator accessed by the system.

Abstract: Methods and systems for particle focusing to increase assay throughput and sensitivity in microscale systems are provided. The invention includes methods for providing substantially uniform flow velocity to flowing particles in microfluidic devices. Methods of sorting members of particle populations, such as cells and various subcellular components are also provided. Integrated systems in which particles are focused and/or sorted are additionally included.

Abstract: Methods for monitoring time dependent reactions that comprise providing a flow channel, typically microscale in dimension, flowing at least two reagents into the flow channel and varying the flow rate of the mixture through the flow channel. By increasing and/or decreasing the flow rate of the reagent mixture from the point of mixing to the point of detection, one alters the amount of reaction time, allowing monitoring reaction kinetics over time.

Abstract: The present invention provides a microfluidic system for fast, accurate and low cost electrophoretic analysis of materials in the fields of chemistry, biochemistry, biotechnology, molecular biology and numerous other fields. Light from periodically spaced regions along a channel in the microfluidic system are received by a photodetector. The intensity of light received by the photodetector is modulated by the movement of species bands through the channel under electrophoretic forces. By Fourier analysis, the velocity of each species band is determined and the identification of the species is made by its electrophoretic mobility in the channel.

Abstract: The present invention is generally directed to improved methods, structures and systems for interfacing microfluidic devices with ancillary systems that are used in conjunction with such devices. These systems typically include control and monitoring systems for controlling the performance of the processes carried out within the device, e.g., controlling internal fluid transport and direction, monitoring and controlling environmental conditions and monitoring results of the processes performed, e.g., detection.

Abstract: The present invention generally provides improved methods of fabricating polymeric microfluidic devices that incorporate microscale fluidic structures, whereby the fabrication process does not substantially distort or deform such structures. The methods of the invention generally provide enhanced bonding processes for mating and bonding substrate layers to define the microscale channel networks therebetween.

Abstract: Microfluidic devices for performing integrated reaction and separation operations. The devices have a planar substrate having a first surface with an integrated channel network disposed therein. The reaction region in the integrated microscale channel network has a mixture of at least first and second reactants located therein, wherein the mixture interacts to produce one or more products. The reaction region is configured to maintain contact between the first and second reactants contained within it. The device also includes a separation region in the integrated channel network, where the separation region is configured to separate the first reactant from the product, when the first reactant and product are flowing through the separation region.

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: Transmembrane potential measurement methods using cationic dyes, and anionic dyes are provided. Compositions of the cationic and anionic dyes and microfluidic systems which include the dyes and membranes are provided in conjunction with processing elements for transmembrane potential measurements.

Abstract: The present invention is generally directed to improved microfluidic devices and systems, and particularly to a microfluidic device which comprises a planar body structure, at least a first channel network comprising intersecting channels disposed within the body structure wherein the first channel network is contained within an area of the planar body structure that is less than about 6 cm2; and a holder assembly configured to receive the body structure, the holder assembly having at least one aperture disposed therethrough from an upper surface to a lower surface thereof, and wherein the body structure is fixedly mounted to the holder assembly.

Abstract: Methods of performing fast polymerase mediated reactions are provided. These reactions can be used in an inefficient fashion in the cycles of the polymerase mediated reactions to produce product at a much faster rate than conventional polymerase mediated reaction methods. Integrated systems for performing these methods are also provided.

Abstract: Microfluidic devices are provided for the performance of chemical and biochemical analyses, syntheses and detection. The devices of the invention combine precise fluidic control systems with microfabricated polymeric substrates to provide accurate, low cost miniaturized analytical devices that have broad applications in the fields of chemistry, biochemistry, biotechnology, molecular biology and numerous other fields.

Abstract: Throughput rates for microfluidic serial analysis systems are optimized by maximizing the proximity and speed with which multiple different samples may be serially introduced into a microfluidic channel network. Devices are included that include optimized parameters based upon desired throughput rates for a given set of reagents, reaction times and the like.

Abstract: Methods and systems for particle focusing to increase assay throughput in microscale systems are provided. The invention includes methods for providing substantially uniform flow velocity to flowing particles in microfluidic devices. Methods of sorting members of particle populations, such as cells and various subcellular components are also provided. Integrated systems in which particles are focused and/or sorted are additionally included.

Abstract: An analytical or preparatory microfluidic system is disclosed which generally comprises a base unit comprising a first adapter interface array; a first adapter plate selected from a set of a plurality of different adapter plates, wherein the first adapter plate comprises a base unit interface array that is complementary to the first adapter interface array, and a first substrate interface array, wherein the first adapter plate is removably coupled to the base unit such that energy passes from the base unit to the adapter plate through the first adapter and base unit interface arrays. The system further comprises a first microfluidic substrate selected from a set of a plurality of different microfluidic substrates, the first microfluidic substrate comprising a plurality of mesoscale channels disposed therein and a second adapter interface array, wherein the second adapter interface array is complementary to the first substrate interface array.

Abstract: Methods and systems for designing optimized fluidic channel networks for performing different analytical operations, which include the steps of selecting a driving force, identifying at least a first reaction parameter, and designing the channel network by determining channel lengths and cross-sectional dimensions that are optimized for the reaction requirements in view of the selected driving force. Preferred methods are used to design integrated microscale fluidic systems.

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 microfluidic devices and systems that utilize optical detection systems, and where one or more light altering optical elements are integrated into the body structure of the microfluidic device. The resulting devices perform at least a portion of the optical manipulations used in the optical detection method employed.