Abstract: The present invention refers to a droplet-based miniaturized device with on-demand droplet-trapping, -fusion, and -releasing. The device makes use of different electrical fields for directing droplets into microwells and releasing them from the same. In another aspect, the present invention refers to a system comprising such a microfluidic device and a method of operating it.

Abstract: A display medium includes a pair of substrates, a dispersion medium sealed between the pair of substrates, a migrating particle group dispersed in the dispersion medium, and a surface layer provided on at least one of the facing surfaces of the pair of substrates and including a polymer compound that is a copolymer containing the following constitutional unit (A) and constitutional unit (B), X represents a group containing a silicone chain, Ra1 and Ra2 each independently represent a hydrogen atom or a methyl group, Rb2 represents an organic group containing a substituted or unsubstituted phenyl group, n1 and n2 each represent mol % of the constitutional unit relative to the whole copolymer and satisfy 0<n1<50 and 0<n2<80, respectively, and n represents a natural number of 1 or more and 3 or less.

Abstract: Photochromic materials that are useful for a variety of applications, including for making various unit functions of fluidic devices, particularly microfluidic devices, such as microchannels, valves and gates, using spiropyran materials, such as a polymeric composition comprising a spiropyran. In certain disclosed embodiments the spiropyran is admixed with a polymeric material. For example, the spiropyran may be intercalated into a polyalkylene or polyalkylene phthalate. The spiropyran also may be polymerized with at least one additional monomer to form a heteropolymer, such as by polymerization with styrene, styrene derivatives, acrylate and acrylate derivatives. The spiropyran compositions can be used to make, for example, a photoactuatable valve, a fluidic channel, etc. The valve may be associated with a microchannel, including photochromic microchannel. In certain disclosed embodiments, the valve, at least one microchannel, or both, are re-patternable by light exposure.

Abstract: A molecular dispenser includes a molecular reservoir comprising a plurality of charged molecules; a nanopore proximate the molecular reservoir, the nanopore comprising a first set of locking electrodes configured to establish an electrostatic potential barrier therein and a second set of locking electrodes configured to establish a second electrostatic potential barrier therein; a first drag electrode arranged within the molecular reservoir; and a control unit, wherein the control unit is configured to apply an oscillating voltage across the first set of locking electrodes and a bias voltage to the first drag electrode to control flow of individually charged molecules from the molecular reservoir through the nanopore.

Abstract: Cassette bodies for use with electrophoresis apparatus can be formed of a single piece of molded or machined plastic. Such cassette bodies can include a plurality of channels that pass through the cassette body, from a proximal end to a distal end. Such channels can be defined by upper and lower chambers. The upper chambers can be in fluid communication with a first buffer pool through a semi-permeable membrane, and the lower chambers can be in fluid communication with a second buffer pool. An electric current can be passed through the first and second buffer pools, and then reversed, to perform an electrophoresis operation that can separate a biomolecule of interest from free probes, and provide for convenient collection of said biomolecule of interest.

Abstract: A multiplexed emitter source distributor electrode, a related multiplexed electrospray nozzle, a related multiplexed electrospray apparatus and a related coating method that uses the multiplexed electrospray apparatus are all predicated upon at least one of: (1) a linear emitter source density greater than about 15 emitter sources per centimeter; and (2) an area emitter source density greater than about 225 emitter sources per square centimeter. The distributor electrode comprises other than a silicon material (i.e., a metal, metal alloy, ceramic or polymer material). The distributor electrode may be fabricated using a computerized numerical control method that provides the coating method with enhanced uniformity. The nozzle and the apparatus may also use a stepped slotted extractor electrode.

Abstract: Improved electrochemical biosensor arrays and instruments are disclosed herein. Methods of making and using the electrochemical biosensor instruments are also disclosed. An electrochemical biosensor array can include an array of microelectrodes disposed on a substrate. Each microelectrode can include a conducting electrode material disposed on a portion of the substrate, a first polymeric layer disposed on at least a portion of the conducting electrode material, a second polymeric layer disposed on at least a portion of the first polymeric layer, and a capture molecule that is in physical communication with the second polymeric layer.

Abstract: A method of actuating, comprising: filling at least a portion of a tube (21) with a liquid (19) containing electrolytes, the tube (21) having an inner surface that is electrically chargeable when in contact with the liquid (19); positioning an object (28) in fluid communication with the liquid in the tube; and applying an electrical field (46) along a lengthwise axis across the tube at said portion for producing a pressure in the liquid. The pressure in the liquid exerts a force on the object so as to actuate the object (28, 30). An actuator (20) is also disclosed.

Abstract: Droplet actuators for conducting droplet operations, such as droplet transport and droplet dispensing, are provided. In one embodiment, the droplet actuator may include a substrate including, droplet operations electrodes arranged for conducting droplet operations on a surface of the substrate; and reference electrodes associated with the droplet operations electrodes and extending above the surface of the substrate. Other embodiments of droplet actuators and methods of loading and using such droplet actuators are also provided.

Abstract: A technique for embedding a nanotube in a nanopore is provided. A membrane separates a reservoir into a first reservoir part and a second reservoir part, and the nanopore is formed through the membrane for connecting the first and second reservoir parts. An ionic fluid fills the nanopore, the first reservoir part, and the second reservoir part. A first electrode is dipped in the first reservoir part, and a second electrode is dipped in the second reservoir part. Driving the nanotube into the nanopore causes an inner surface of the nanopore to form a covalent bond to an outer surface of the nanotube via an organic coating so that the inner surface of the nanotube will be the new nanopore with a super smooth surface for studying bio-molecules while they translocate through the nanotube.

Abstract: An active-matrix device is provided which includes a plurality of array element circuits arranged in rows and columns; a plurality of source addressing lines each shared between the array element circuits in corresponding same columns; a plurality of gate addressing lines each shared between the array element circuits in corresponding same rows; a plurality of sensor row select lines each shared between the array element circuits in corresponding same rows, wherein each of the plurality of array element circuits includes: an array element which is controlled by application of a drive voltage by a drive element; writing circuitry for writing the drive voltage to the drive element, the writing circuitry being coupled to a corresponding source addressing line and gate addressing line among the plurality of source addressing lines and gate addressing lines; and sense circuitry for sensing an impedance presented at the drive element, the sense circuitry being coupled to a corresponding sensor row select line; and

Abstract: The invention provides fluidic devices having incorporated electrodes. One device comprises a card and first and second caddy segments. The first caddy segment comprises first and second electrodes. The second caddy segment comprises first and second reservoirs disposed on a first surface of the second segment, a channel disposed on a second surface of the second segment, and first and second vias extending between the first and second surfaces. The first caddy segment is attached to the first surface of the second caddy segment. The card is attached to the second surface of the second caddy segment such that the card provides a closed surface for the device.

Abstract: A method for dispensing charged particles includes applying a bias voltage to promote motion of charged molecules through a nanopore, detecting passage of at least one charged molecule through the nanopore, and manipulating an electrostatic potential barrier inside the nanopore, so as to prevent movement of additional charged molecules through the nanopore.

Abstract: A device for the removal of toxic substances from biofluids has an electrocatalytic decomposition filter positioned between an inlet and an outlet. The filter includes a DC power source, a set of electrodes with a catalytic surface or in direct contact with sorbents offering catalytic activity, and an electrosorption filter for removing toxic substances.

Abstract: The device comprises first and second contact pads having a contact surface. The first and second contact pads move with respect to one another between an ohmic contact position between these contact surfaces and another position. The device further comprises means for applying a non-uniform electric field around the first contact pad. The electric field has a component in a direction parallel to the contact surface of the first contact pad. A fluid with a first dielectric permittivity value is arranged between the first contact pad and the decontamination electrode. The decontamination device and the fluid are configured in such a way that the electric field generates a force directed towards the decontamination electrode on a contaminant, by dielectrophoresis.

Abstract: A device and method of using same, wherein the device includes a collimated light source operable to generate a collimated light source beam, the collimated light source beam comprising a beam cross-section. The device further includes at least one body defining a first channel in a first plane, the first channel comprising a first channel cross-section, the first channel being oriented to receive the collimated light source beam such that the beam cross-section completely overlaps the first channel cross-section. Optionally, the body defines a second channel in a second plane orthogonal to the first plane, wherein the body defines a third channel in a third plane orthogonal to the first plane.

Abstract: An apparatus and method fox micropumping is disclosed. The apparatus includes a virtual or physical microchannel and at least two hydrophobic electrode patches on a surface or two electrode patches disposed underneath a dielectric film proximate to the channel. Each of the electrode patches modifies a surface property between hydrophobic and hydrophilic states in response to an electrical potential applied between the liquid and the electrode, and the electrical potential is provided to digitize the liquid, drive the liquid segments, and mix different liquids.

Abstract: A dielectrophoresis apparatus for separating particles from a sample, including an apparatus body; a dielectrophoresis channel in the apparatus body, the dielectrophoresis channel having a central axis, a bottom, a top, a first side, and a second side; a first mesa projecting into the dielectrophoresis channel from the bottom and extending from the first side across the dielectrophoresis channel to the second side, the first mesa extending at an angle to the central axis of the dielectrophoresis channel; a first electrode extending along the first mesa; a second mesa projecting into the dielectrophoresis channel from the bottom and extending from the first side across the dielectrophoresis channel to the second side, the second mesa extending at an angle to the central axis of the dielectrophoresis channel; a space between at least one of the first electrode and the second side or the second electrode and the second side; and a gap between the first electrode and the second electrode.

Abstract: The present invention provides a new and improved oligonucleotide detection method based on the nanopore technology with a probe containing a complementary sequence to the target oligonucleotide and a terminal extension at the probe's 3? terminus, 5? terminus, or both termini. The improved nanopore sensor with the probe enables sensitive, selective, and direct detection, differentiation and quantification of target oligonucleotides such as miRNAs. The inventive detection method may also be employed as a non-invasive and cost-effective diagnostic method for cancer detection based on miRNA levels in the patient's blood sample.

Abstract: Methods, systems, and apparatuses for extracting non-polar lipids from microalgae are achieved using a lipid extraction device having an anode and a cathode that forms a channel and defines a fluid flow path through which an aqueous slurry is passed. An electromotive force is applied across the channel at a gap distance in a range from 0.5 mm to 200 mm to cause the non-polar lipids to be released from the algae cells. The non-polar lipids can be extracted at a high throughput rate and with low concentrations of polar lipids such as phospholipids and chlorophyll.

Abstract: The present invention uses the principles of electrochemical ion absorption (charging) and ion desorption (discharge), and relates to a continuous flow-electrode system, a high-capacity energy storage system, and a water treatment method using the same, in which high-capacity electric energy is stored as electrode materials of a slurry phase and electrolytes simultaneously flow in a successive manner within a fine flow channel structure formed on an electrode. More specifically, the present invention relates to a continuous flow-electrode system, an energy storage system, and a water treatment method, wherein electrode active materials consecutively flow in a slurry state whereby a high capacity is easily obtained without enlarging or stacking electrodes.

Abstract: A three-dimensional nanochannel device and a method of manufacturing the same are provided. In the device, a first substrate, a second substrate, and a channel layer sandwiched by the first and the second substrates are included. At least one channel is constituted by the first and the second substrates and the channel layer and includes a fluid inlet, a fluid outlet, and at least one condensed channel between the fluid inlet and the fluid outlet. The condensed channel at least has a first size and a second size on an X-Y plane and has a third size and a fourth size on an X-Z plane. A difference between the first size and the second size is about at least two orders in scale, and a difference between the third size and the fourth size is about at least two orders in scale.

Abstract: An electrophoretic cell and methods of switching an electrophoretic cell and moving charged species in an electrophoretic cell employ differential electrophoretic mobilities and a time-varying electric field. The methods include providing first and second charged species that are oppositely charged and have different mobilities. The method of switching further includes inducing a net motion of both of the charged species using the time-varying applied electric field. The induced net motion results in either the first charged species being moved toward the electrode and the second charged species remaining essentially motionless or both of the charged species being moved toward the same electrode. The electrophoretic cell includes the first and second charged species with opposite charge and different mobilities, and further includes the time-varying applied electric field that provides the net motion of the charged species.

Abstract: Liquid droplet manipulation instrument has electrode array for inducing movement of a droplet by electrowetting, substrate supporting the array and control with electrode selector connected to a voltage control. The selector selects each electrode and provides each with a controlled voltage. The control includes central processing unit for providing the selected electrode with an individual voltage pulse which is a drive voltage or a ground voltage or a stop voltage. The control defines a path for movement of a liquid portion of a larger volume that covers more than one electrode by the simultaneous selection of a group of two or more subsequent drive electrodes and to provide each selected drive electrode with a drive voltage pulse along the path. The control simultaneously provides a group of two or more electrodes adjacent to or identical with the pulsed drive electrodes, with a ground or stop voltage pulse.

Abstract: Embodiments of electrophoresis systems, devices, and associated methods of analysis are described herein. In one embodiment, an electrophoresis device includes a first electrode having a first polarity, a second electrode having a second polarity, and a substrate. The substrate includes a first channel having a first section with a first cross-sectional area and a second section with a second cross-sectional area. The first end is electrically coupled to the first electrode, and the second end is electrically coupled to the second electrode. The first cross-sectional area is greater than the second cross-sectional area in a first dimension and in a second dimension generally orthogonal to the first dimension.

Abstract: Embodiments of analysis systems, electrophoresis devices, and associated methods of analysis are described herein. In one embodiment, a method of analyzing a sample containing an electrolyte includes sequentially introducing a leading electrolyte, a sample electrolyte, and a trailing electrolyte into a extraction channel carried by a substrate. The extraction channel has a constriction in cross-sectional area. The method also includes applying an electrical field to separate components of the sample electrolyte into stacks and to concentrate the separated components by forcing the sample electrolyte to migrate through the constriction in the extraction channel. Thereafter, the applied electrical field is removed and the separated and concentrated components of the sample are detected in a detection channel carried by the substrate.

Abstract: A gel cassette adaptor for use with an electrophoresis system gel cassette is disclosed herein. The gel cassette adaptor allows a single gel cassette to be compatible with more than one electrophoresis system. In one example embodiment, the gel cassette adaptor includes an open sided trough having an attachment perimeter and an attachment flange coupled to the attachment perimeter. The attachment flange is designed to be compatible for mating with a gel cassette that is compatible with a first electrophoresis system. After attachment of the gel cassette adaptor, the resulting gel cassette assembly is compatible with a second electrophoresis system. Also provided is a gel cassette that includes a stabilizer post that connects the cassette plates to maintain a constant gap width between the plates during electrophoresis. In reducing deformation of the gap space between plates during gel runs, the stabilizer post can improve electrophoresis results for wide format gels.

Abstract: An integrated electro-magnetohydrodynamic pump may include a flow channel adapted to contain a fluid to be pumped and a plurality of electrodes positioned adjacent the flow channel. A voltage controller operatively associated with the plurality of electrodes applies a voltage potential on the plurality of electrodes. A plurality of magnets are also positioned adjacent the flow channel. A voltage controller operatively associated with the plurality of magnets changes magnetic fields produced by the plurality of magnets with respect to the flow channel. The voltage controller and the magnet controller are operable to pump fluid contained in the flow channel by an electro-osmotic flow process and by a magnetohydrodynamic flow process.

Abstract: Electrowetting devices coated with one or more polymeric layers and methods of making and using thereof are described herein. The coatings may be formed in a single layer or as multiple layers. In one embodiment the first layer deposited serves as an insulating layer of high dielectric strength while the second layer deposited serves as a hydrophobic layer of low surface energy. These materials may themselves be deposited as multiple layers to eliminate pinhole defects and maximize device yield. In one embodiment the insulating layer would be a vapor deposited silicone polymeric material including, but not limited to, polytrivinyltrimethylcyclotrisiloxane or polyHVDS. In another embodiment the insulating layer may be a vapor deposited ceramic such as SiO2 with very little carbon content. In a further embodiment the insulating layer may be composed of alternating layers of a siloxane material and a ceramic material.

Abstract: The present invention provides control methods, control systems, and control software for microfluidic devices that operate by moving discrete micro-droplets through a sequence of determined configurations. Such microfluidic devices are preferably constructed in a hierarchical and modular fashion which is reflected in the preferred structure of the provided methods and systems. In particular, the methods are structured into low-level device component control functions, middle-level actuator control functions, and high-level micro-droplet control functions. Advantageously, a microfluidic device may thereby be instructed to perform an intended reaction or analysis by invoking micro-droplet control function that perform intuitive tasks like measuring, mixing, heating, and so forth. The systems are preferably programmable and capable of accommodating microfluidic devices controlled by low voltages and constructed in standardized configurations.

Abstract: A cartridge (1) comprises a working film (10) for manipulating samples in liquid droplets with an electrode array (20) when the working film (10) of the cartridge (1) is placed on said electrode array (20).

Abstract: A matrix electrode-controlling device for driving a droplet according to this aspect of the present invention comprises a substrate, a dielectric layer positioned on the substrate, a plurality of control electrodes positioned in the dielectric layer in a matrix manner, and a ground electrode positioned at a predetermined position around the control electrodes without generating electromagnetic shielding effect. The control electrodes in the same row are electrically connected to form a plurality of lateral controlling rows and the control electrodes in the same column are electrically connected to form a plurality of longitudinal controlling columns, and the droplet is driven to move on or above the dielectric layer by biasing the ground electrode to the ground voltage and applying a predetermined voltage to one of the controlling rows and/or to one of the controlling columns to undergo the predetermined assaying operation.

Abstract: Methods are provided for manipulating droplets. The methods include providing the droplet on a surface comprising an array of electrodes and a substantially co-planer array of reference elements, wherein the droplet is disposed on a first one of the electrodes, and the droplet at least partially overlaps a second one of the electrodes and an intervening one of the reference elements disposed between the first and second electrodes. The methods further include activating the first and second electrodes to spread at least a portion of the droplet across the second electrode and deactivating the first electrode to move the droplet from the first electrode to the second electrode.

Abstract: A microfluidic device for droplet manipulation includes a substrate, a plurality of electrically addressable thin-film electrodes disposed on the substrate, at least one of the plurality of electrodes comprising a heating element in the form of a patterned electrode. A hydrophilic region is disposed in or above a portion of the heating element. The hydrophilic region may be permanent or electronically actuable. The thin-film electrodes have multi-function capabilities including, for instance, heating, temperature sensing, and/or sample actuation.

Abstract: On-board reagent storage, handling, and dispensing apparatuses and methods for droplet actuator systems are provided. In one embodiment, a fluidic analyzer is provided and includes a droplet actuator including a substrate including a plurality of electrodes configured to actuate a droplet and a reagent storage component in selective fluid communication with the droplet actuator and including a reagent configured to combine with a solvent at a time of use. In another embodiment, a method of conducting fluidic analysis is provided and includes storing a reagent within a reagent storage component in fluid communication with a droplet actuator including a plurality of electrodes configured to actuate a droplet and combining the reagent with a solvent at a time for use within the droplet actuator.

Abstract: A capillary electrophoresis apparatus capable of efficiently using a polymer in a polymer container is provided. The present invention relates to a mechanism for efficiently using the polymer in the polymer container in a capillary electrophoresis apparatus for the electrophoresis with a separation medium filled in a capillary. According to the present invention, since the polymer in the polymer container is not contacted with the air, deterioration of the polymer by oxidation can be prevented.

Abstract: The invention relates to the use of MS compatible surfactants in free-flow electrophoretic methods, which allow the separation of analytes with differentiated electrophoretic mobility. The surfactant is preferably a cleavable surfactant, such as PPS.

Abstract: A liquid droplet manipulation system has a substrate with at least one electrode array and a central control unit for controlling selection of individual electrodes of the electrode array and for providing the electrodes with individual voltage pulses for manipulating liquid droplets by electrowetting. A working film is placed on top of the electrodes for manipulating samples in liquid droplets with the electrode array. At least one selected individual electrode of the electrode array is configured to be penetrated by light of an optical detection system for the optical inspection or analysis of samples in liquid droplets that are located on the working film. Also disclosed is working film that is to be placed on the electrode array and a cartridge that includes such a working film for manipulating samples in liquid droplets.

Abstract: A method of analysis, instrument for analysis and device for use in such an instrument are provided, which perform a number of processes need to reach a useful result in the context of a wide variety of samples. The sequence of those processes being optimised. A device, instrument using the device and method of use are also provided which offer reliable performance of a heating based process, with minimal condensation and/or sample loss issues.

Abstract: A device for forming at least one circulating flow, or vortex, at the surface of a drop of liquid, including at least two first electrodes forming a plane and having edges facing each other, such that the contact line of a drop, deposited on the device and fixed relatively to the device, has a tangent forming, when projected onto the plane of the electrodes, an angle between 0° and 90° with the edges facing each other of the electrodes.

Abstract: A cartridge manipulates samples in liquid droplets with an electrode array when a working film is placed on the array. The cartridge has a body with lower surface and wells to hold samples, each with a bottom opening to release liquid. A piercable bottom structure seals the bottom openings. A working film below the body has a hydrophobic upper surface. A peripheral spacer connects the working film to the body and forms a gap is between the body and surface. A top piercing system located in at least one of the wells has a piston and a piercing element, the piston being movable in the well and the piercing element piercing the piercable bottom structure for releasing a sample from a well into the gap.

Abstract: A fluidic device includes a porous substrate, a wetting region extending through a first portion of the porous substrate from a first side of the substrate, in which the wetting region is permeable to fluid transport, and a non-wetting region extending through a second portion of the porous substrate from a second side of the substrate, in which the non-wetting region is operable to switch between a first state impermeable to fluid transport and a second state permeable to fluid transport.

Abstract: Techniques are generally described that include electrokinetic pumping an emulsion comprising an ionic fluid and a nonpolar fluid to promote flow of the ionic fluid by electro-osmotic flow and drag the nonpolar fluid by viscous drag forces. In some examples, the electrokinetic pump may be utilized to deliver one or more reagents within a fluidic reactor system, such as a micro-scale reactor system. In some additional examples, a reagent may be dissolved in the nonpolar fluid of a first emulsion and pumped through the electrokinetic pump to a mixing channel to allow the reagent of the first emulsion to react with a reagent of second emulsion to form a reactive product.

Abstract: A microfluidic separation device is provided that includes a sample channel having a first sample channel region and a second sample channel region, where a cross-section of the first sample channel region is smaller than a cross-section of the second sample channel region. The invention further includes a detection region having a first detection region and a second detection region, where a cross-section of the first detection region is larger than a cross-section of the second detection region and the second sample channel region is connected to the first detection region. Additionally, the invention includes a marker input channel disposed to input markers into the second sample channel region, where the markers are larger than the cross-section of the first sample channel region and the cross-section of the second detection region, where the markers collect in the first detection region.

Abstract: Provided is a device and method of manipulating particles. The device includes: a channel for accommodating an electrolyte solution including particles to be manipulated; an anode and cathode for imposing a direct current (DC) electric field on the channel; metal strip(s) attached to an inner wall of the channel and resulting in induced-charge electroosmosis near a surface of the channel; a DC power supply unit for supplying a DC voltage to the anode and the cathode of the channel; control electrodes on both sides of the metal strip(s) to locally tune the induced-charge electroosmosis on the metal strip(s) regardless of the global electric field across the channel; and a DC power supply unit for supplying a DC voltage to the control electrodes.

Abstract: Reversible flow may be provided in certain EHD device configurations that selectively energize corona discharge electrodes arranged to motivate flows in generally opposing directions. In some embodiments, a first set of one or more corona discharge electrodes is positioned, relative to a first array of collector electrode surfaces, to when energized, motivate flow in a first direction, while second set of one or more corona discharge electrodes is positioned, relative to a second array of collector electrode surfaces, to when energized, motivate flow in a second direction that opposes the first. In some embodiments, the first and second arrays of collector electrode surfaces are opposing surfaces of individual collector electrodes. In some embodiments, the first and second arrays of collector electrode surfaces are opposing surfaces of respective collector electrodes.

Abstract: Apparatus and methods are provided for liquid manipulation utilizing electrostatic field force. The apparatus is a single-sided electrode design in which all conductive elements are embedded on the first surface on which droplets are manipulated. An additional second surface can be provided parallel with the first surface for the purpose of containing the droplets to be manipulated. By performing electrowetting based techniques in which different electrical potential values are applied to different electrodes embedded in the first surface in a controlled manner, the apparatus enables a number of droplet manipulation processes, including sampling a continuous liquid flow by forming individually controllable droplets from the flow, moving a droplet, merging and mixing two or more droplets together, splitting a droplet into two or more droplets, iterative binary mixing of droplets to obtain a desired mixing ratio, and enhancing liquid mixing within a droplet.

Abstract: Systems and methods are provided for sample processing. A device may be provided, capable of receiving the sample, and performing one or more of a sample preparation, sample assay, and detection step. The device may be capable of performing multiple assays. The device may comprise one or more modules that may be capable of performing one or more of a sample preparation, sample assay, and detection step. The device may be capable of performing the steps using a small volume of sample.

Abstract: 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.

Abstract: A device for real time monitoring of fluid composition in microfluidic devices. The invention can be integrated into any microfluidic device where fluid moves along a pathway with a measurement region consisting of at least two measurement electrodes. The fluidic pathway can contain an unbound droplet, a droplet confined in at least one aspect, or a continuous flow. The device also includes control circuitry connected to measurement electrodes that allows for the determination of the droplet composition by measuring at least one of capacitance, resistance, or impedance between said electrodes. This invention can (1) measure droplet composition, (2) compare composition against a known sample, (3) monitor droplet mixing, (4) control mixing to achieve specific mixing ratios, (5) measure the particle concentration within a droplet, (6) determine the position of particles in a droplet, and (7) monitor chemical reactions. These functions call all be performed in real time.