Abstract: The present invention provides a unique and highly accurate method for generating molecular arrays of very high density on porous surfaces. The method involves the application of focused acoustic energy to each of a plurality of fluid-containing reservoirs to eject a small fluid droplet—on the order of 1 picoliter or less—from each reservoir to a site on a porous substrate surface. High density molecular arrays are provided as well, in which greater than about 62,500 molecular moieties, serving as array elements, are present on a porous surface. Biomolecular arrays that can be generated using focused acoustic ejection include oligonucleotide arrays and peptidic arrays.

Abstract: A method and system for circulating sample solution within a reaction chamber containing a microarray. The reaction chamber contains, on each side, a shallow vertical and a deep vertical well at the corners of the microarray. The vertical wells having a gap between the active surface of the microarray and the bottom of the reaction chamber are filled with sample solution. As the reaction chamber is rotated, sample solution from the deep vertical well displaces sample solution in the gap between the active surface of the microarray and the bottom of the reaction vessel, and sample solution from that gap is, in turn, displaced into the shallow vertical well, from which it flows along the inner surface of a cover strip above the microarray back to the deep vertical well.

Abstract: A microfluidic device which operates without the need for an external power source. The device includes a body structure, at least one microscale channel within the structure, a port for introducing fluid into the channel, and a power source internal to the structure for propelling the fluid through the channel. Various structures are described which embody the invention.

Abstract: The invention concerns a device for qualifying products containing volatile substances forming an analyte. The devices includes a measuring apparatus (2) provided with an enclosure (21a) and an electronic analyzing circuit (21b) for defining said analyte characteristics, a pumping system (30) for producing a vacuum inside said enclosure, a sampling chamber (16) wherein the analyte is introduced and a capillary (22) for connecting said chamber (16) to said enclosure (21a).

Abstract: A microfluid driving device is provided. The microfluid driving device of this invention comprises microfluid driving platform prepared in a chip, which platform comprises at least two miniature Venturi pumps, at least one microchannel and optionally micro mixers or micro reactors in said microchannel; an external pneumatic flow supply and control module that provides selectively different air flows; and an interface device connecting said microfluid driving platform and said external pneumatic flow supply and control module. The air flows supplied by said the pneumatic flow supply and control module are supplied under selected flow rates and frequencies to said at least two Venturi pumps through said interface device, such that the microfluid inside said microchannel may be driven forward or backward or halt and the transportation, mixing and reaction of the microfluid may be accomplished.

Abstract: An improved cartridge for holding a fluid sample with a small volume is disclosed herein. The cartridge has a test chamber and a vestibule through which the test fluids are inserted into the test chamber. Improved grips are flared-out to aid manipulation. The handle portion is reinforced to prevent flexing, and a prefabricated trough along the edge of the land surface prevents introduction of the adhesive into the region for analysis. The cartridge has a stopper having a dual sealing mechanism, which seals the test chamber inlet between the vestibule and the test chamber, and the mouth of the vestibule so that when the stopper is in place, the test chamber is closed to the admission of air or other contaminants. The vestibule is similarly closed against escape of the overflow from the test chamber. The stopper is composed of a single elastomer. An improved locking mechanism has two flexible walls on either side of the handhold that locks into their respective keepers on the cartridge to provide a secure lock.

Abstract: Methods for testing proper operation of drop ejection units in a multi-ejector system are provided to determine whether the drop ejectors have been properly filled and/or the ejectors are emitting fully formed droplets. The methods include testing the ejectors prior to drop ejection. In this method, a priming system is used wherein fluid received by the priming system is ejected onto a test substrate to allow a scanner to determine the existence of the fluids at selected locations. The selected locations are correlated to the drop ejection units to determine which ejection units do not have biofluid or sufficient biofluid. A further method allows for ejection prior to printing, on a test substrate wherein testing for both the fullness of the ejector units as well as proper emission of the ejectors of droplets may be tested. The ejectors after being primed, eject the biofluids which are then scanned and correlated to each individual ejector.

Abstract: An automated chemical synthesizer including plural reaction vessels, a plurality of liquid containers, at least one liquid dispenser, a liquid amount storage, a dispensing amount calculator, and a liquid shortage detector. The plurality of liquid containers are configured to contain liquid chemicals respectively. The at least one liquid dispenser is configured to dispense the liquid chemicals from the plurality of liquid containers to the plural reaction vessels according to a synthesizing protocol. The liquid amount storage is configured to memorize a present amount of each of the liquid chemicals in the plurality of liquid containers. The dispensing amount calculator is configured to calculate a dispensing amount of each of the liquid chemicals to be dispensed according to the synthesizing protocol.

Abstract: The present invention relates to artificial receptors and arrays or microarrays of artificial receptors or candidate artificial receptors. Each member of the array includes a plurality of building block compounds, typically immobilized in a spot on a support. The present invention also includes the building blocks, combinations of building blocks, arrays of building blocks, and receptors constructed of these building blocks together with a support. The present invention also includes methods of making and using these arrays and receptors.

Abstract: The disclosed pin-lifter can selectively lift pins partially out of a printhead of a spotting instrument and thereby prevent the lifted pins from contacting the substrate during any printing. Methods of using pin-lifters to increase the rate of production of compact microarrays are disclosed.

Abstract: A high throughput microarraying or colony picking robot with an automatic mechanism for exchanging pin heads and an automated washing and drying apparatus. The robot allows a dirty pin head to be deposited on the automated washing and drying apparatus for cleaning without use of the xyz-positioner, while spotting or picking can continue by picking up a clean pin head without having to wait for the dirty pin head to be cleaned. In this way, the speed of operation can be increased without any increase in the acceleration or speed of the x-, y- and z-drives. The dead time normally associated with the washing and drying cycle, which is usually several minutes, is therefore eliminated, and replaced with the much shorter dead time, of only a few tens of seconds, needed for changing between heads.

Abstract: A system for separating an aqueous stream of mixed polynucleotides into a series of length-based polynucleotide fractions and collecting one or more of the length-based polynucleotide fractions into separate containers. The system comprises a separation column containing separation media for separating an aqueous stream of mixed polynucleotides into a series of length-based polynucleotide fractions; a container including one or more single-sample containers; an ejection chamber having a separated sample inlet for receiving the length-based polynucleotide fractions, a waste outlet for discharging uncollected sample, and a capillary-sized fraction outlet positioned to discharge a selected length-based polynucleotide fraction into a single-sample container. The system also includes means for effecting discharge of a selected length-based polynucleotide fraction into the separate container.

Abstract: Systems and method for removing undesirable gas from microfluidic separation devices to prepare them for operation are provided. The microfluidic devices contain separation media that provides a significant fluidic impedance. A vacuum source is used to evacuate gas from, and a positive pressure source is used to introduce liquid into, the microfluidic device to minimize the presence of undesirable bubbles. Where hydrophobic materials are present within the microfluidic device, the liquid may be an organic solvent. Positive pressures of at least about 100 psi are preferably employed. A microfluidic separation device may include multiple separation columns and a distribution network in fluid communication with the columns.

Abstract: A method and device for forming large arrays of polymers on a substrate (401). According to a preferred aspect of the invention, the substrate is contacted by a channel block (407) having channels (409) therein. Selected reagents are delivered through the channels, the substrate is rotated by a rotating stage (403), and the process is repeated to form arrays of polymers on the substrate. The method may be combined with light-directed methodolgies.

Abstract: A coupling system can utilize a first receptacle and a second receptacle to couple syringes together. Syringes can be used to mix viscous material and/or dispense the viscous material. Furthermore, a kit can be provided that contains parts used in mixing and/or dispensing viscous material.

Abstract: A pipette gun and holster apparatus having a remote source of positive and negative air pressure. The holster supports the pipette gun above a work table with the pipette connector oriented generally, vertically downwardly. The holster has a base which may be fastened to a vertical wall. A mounting bracket is fixed to and extends transverse to the base. The bracket has a bottomless socket constructed and arranged to receive and removably hold the pipette gun by inserting the pipette connector into the socket. A switch deactivates the remote air pressure source when the pipette gun is parked in the holster and energizes the remote air pressure source when the pipette gun is removed from the holster. A method of metering fluid using a pipette gun and holster apparatus. The holster is removable fastened to a vertical surface next to or proximate a horizontal work table top.

Abstract: A microfluidic component having a microfluidic channel is joined to an array component having a flexible array substrate. In an embodiment, the array component includes a prefabricated flexible array that couples with the microfluidic component in modular fashion. The modular architecture provides for different combinations of microfluidic components and array components that can be used to create customized processing and analysis tools.

Abstract: Systems, including apparatus and methods, for microfluidic processing and/or analysis of samples. The systems include a microfluidic device having a substrate and a thin-film layer formed on the substrate. The thin-film layer may be included in electronics formed on the substrate. The electronics may provide electronic devices configured to sense or modify a property of the sample. The thin-film layer defines an opening for routing movement of fluid and/or sample within the device.

Abstract: Embodiments of the invention are directed to microfluidic devices. In one embodiment, a microanalysis chip comprises a body having at least one transfer-separation channel with a channel bottom that has a bottom opening. The transfer-separation channel terminates in a discharge aperture.

Abstract: Devices, and methods for the use of same, for collecting and assaying a biological fluid in a single step. One method provides means to control and direct the flow of a sample of the biological fluid directly onto an assay test strip by disposing the assay test strip within a flow control channel in which the internal ambient pressure is maintained in substantial equilibrium with the ambient pressure outside of the flow control channel, such that essentially no pressure gradient is formed within the flow control channel. The devices include the flow control channel, at least one assay test strip and a fluid sample collection container, such as a urine cup, for insertion of the flow control channel therein.

Abstract: A device for applying a plurality of microdroplets onto a substrate comprises a dosing head substrate (10) having a plurality of nozzle openings (16) formed therein. For each nozzle opening (16), there is provided a media portion (18) to be filled with a liquid to be dosed. There is provided a deformable component (28) that is arranged adjacent the media portions (18). Finally, the device comprises an actuating means (34) for actuating the deformable component (30) such that the deformable component (30) deforms into the media portions (18) so as to simultaneously expel microdroplets from the plurality of nozzle openings (16).

Abstract: Identically shaped spots can be formed sequentially and stably by a spotting pin comprising a bar-like plunger 20. Four projections each formed in the shape of a top portion of a quadrangular pyramid are formed on the head of the plunger 20. The apexes 21 of the quadrangular pyramids constituting the projections are located inside a virtual plane extending from the peripheral wall of the plunger.

Abstract: A fluid specimen collecting and testing device has two chambers each sealable by a lid. A first chamber has a portion of the specimen volume for carrying out a field test. A second chamber preserves an untainted portion of the fluid for more rigorous laboratory testing. A volume of fluid is temporarily allowed to pass from one chamber to the other through a sealable passageway. One lid carries one or more chromatic graphic reaction testing strips.

Abstract: A device for collecting a blood sample from a plastic segment tube into a receptacle uses a cylindrical housing containing a hollow needle to puncture the segment tube as it is inserted into the upper port of the device. A series of ribs with medial edges are arranged in a radial pattern around the needle within the upper port to guide and support the segment tube as it is inserted. The ribs are separated by slots that also guide the sealed end of the segment tube. An annular recess around the lower port of the device holds the rim of the receptacle and allows blood released by the punctured segment tube to drain into the receptacle. The annular recess accommodates a wide range of test tube diameters, and exerts only a downward force on the rim of the receptacle when a segment tube is inserted into the upper port of the device.

Abstract: Liquid dispensing module and methods for dispensing a heated liquid onto a substrate. The dispensing module includes a dispenser body receiving liquid from a heated liquid distribution manifold and an actuator having a housing with an air piston movable in an air cavity and a solenoid valve for pressurizing the air cavity. Movement of the air piston controls a flow-regulating mechanism for selectively dispensing liquid from the dispenser body. A thermally insulating shield may be provided for reducing heat transfer from the manifold and/or dispenser body to the actuator so that the solenoid valve can be mounted directly to the housing and the effective volume of the air cavity can be reduced. The cycle time of the liquid dispensing module may be specified by selecting an initial volume of the air cavity and an effective valve flow coefficient for the actuator that characterizes the air flow to the air cavity.

Abstract: For depositing fluid dots in an array, e.g., for microscopic analysis, a deposit device, e.g. a pin, cooperating with a fluid source defines a precisely sized drop of fluid of small diameter on a drop carrying surface. Transport mechanism positions the device precisely over the receiving surface and drive mechanism moves the deposit device toward and away from the surface. By repeated action, minute drops of fluid can be deposited precisely in a dense array, preferably under computer control. The drop-carrying surface shown has a diameter less than 375, preferably less than 300, preferably between about 15 and 250 micron, and is bound by a sharp rim that defines the perimeter of the fluid drop. The deposit device is compliant in the direction of deposition motion, e.g. by overcoming resistance of a resilient member. When depositing, the deposit device is laterally constrained to a reference position, e.g.

Abstract: A dropping tool for transferring drops of a liquid onto a substrate wherein a surface of the dropping tool for contact with the liquid has a first region which exhibits an affinity to the liquid to be transferred directly surrounded by a second region which exhibits a lower affinity to the liquid to be transferred than the first region; the topography of the first and second regions and the relative affinities of the first and second regions for the liquid to be transferred being selected such that when the dropping tool is dipped into and then removed from a source of the liquid to be transferred, the liquid adheres to the first region without substantially any adherence of the liquid to the second region. A dropping tool for transferring drops of liquid onto a substrate, the dropping tool comprising a tip, at least one surface tapered towards the tip, and a capillary channel which leads from a position of the tapered surface remote from the tip to a reservoir located within the dropping tool.

Abstract: The present invention relates to a cap which can form an essentially leak-proof seal with a vessel capable of receiving fluid specimens for clinical analysis and diagnosis. To minimize potentially contaminating contact between the fluid specimen and humans or the environment, the present invention features a cap which is penetrable by a plastic pipette tip or other fluid transfer device, and may include a plurality of striations which were discovered to further improve penetrability of the cap. In this way, substances can be dispensed into or withdrawn from the vessel without having to physically separate the cap from the vessel. Also featured are fluid transfer devices and caps having surface ribs and/or grooves which aid in creating passageways for venting displaced air from a penetrated collection device.

Abstract: A sample processing device [700] comprises an elongated body [101] with a septum seal [109] on one end and a drip tube [731] on the second end. A small-diameter through-chamber [103] in the body provides a receiving and alignment chamber for a hypodermic needle [109] inserted into the septum. A sample processing chamber [709] provides a location for processing elements such as filters and adsorption or absorption frits [135,137]. Sample fluid injected into, or withdrawn from, the device by the hypodermic needle communicates with a bottom opening [701] of the drip tube via a drip tube nozzle [705], the sample processing chamber and the small-diameter chamber. The device is particularly useful in automated testing where the device is moved to various processing locations by the hypodermic needle.

Abstract: A dispensing apparatus and method is provided for accurately and precisely dispensing various desired patterns of reagent onto a substrate or other receptive surface or receptacle. The invention provides high-speed on-the-fly dispensing of various desired reagent patterns as provided by the operator in the form of a graphic bit map file. In one embodiment the dispensing apparatus comprises a dispensing head having an inlet end and an outlet end. The dispensing head is responsive to a first signal to dispense droplets of liquid reagent onto a substrate. The substrate or dispensing head are secured in association with a table or carriage. The table is responsive to a second signal for providing for relative X, X-Y or X-Y-Z motion between the substrate and the dispensing head.

Abstract: A metering tip for use in a clinical analytical apparatus includes a tapered body having at least one interior stepped areas. Each of the stepped areas include a sharp diametrical edge for latching a fluid meniscus being dispensed from the tip and for reducing fluid oscillation during metering.

Abstract: The present invention relates to a ceramic tip and a random access print head for the transfer of microfluidic quantities of fluid. The print head can randomly collect and deposit fluid samples to transfer the samples from a source plate to a target. The print head can also be programmed to create a direct map of the fluid samples from the source plate on the target or to create any desired pattern or print on the target. The tip and print head can be used for a wide variety of applications such as DNA microarraying and compound reformatting. In one preferred embodiment, the tip is used as a capillary or “gravity” pin to draw or collect source fluid and “spot” or deposit the fluid onto the target via physical contact (touch-off). In another preferred embodiment, the tip is used in conjunction with an aspirate-dispense system to actively aspirate source fluid and deposit the fluid via a contact or non-contact approach.

Abstract: The invention relates to a device for manipulating small quantities of liquid on a solid body surface with at least one defined holding area with wetting properties other than the surroundings, whose material is such that the liquid to be manipulated preferably stays in the holding area, whereby the holding area has at least one constriction zone which cannot be overcome by the liquid due to its surface tension in the normal state, and whereby at least one device for generating an external force is provided substantially in the direction of the at least one constriction zone. The invention also relates to a corresponding method for manipulating small quantities of liquid on solid body surfaces and a method for generating a defined quantity of liquid using the method according to the present invention.

Abstract: The invention relates to a closure for a reagent container (7) with a screw-cap or lid (6), comprising a conical insert (4), reaching in the direction of the contents. The conical insert (4) is cut at least once, such that said insert may be bent apart in the lower region thereof and further comprises, for example, an annular step (3) in the middle region thereof. In the rest state the cone completely seals the reagent container. For the removal of liquid, a pipette with a release sleeve (2), in other words, a broadening (2) at a particular separation from the needle end (1), is introduced. The release sleeve contacts the step of the conical insert (3) and produces a separation of the divided walls of the cone. The pipette needle enters the container without making contact with the cone, in other words with the closure. As the pipette needle, complete with release sleeve (2), is withdrawn, the walls of the cone close back together, as the release sleeve (2) is no longer pressing on the step (57).

Abstract: This invention provides reagent array chips having, e.g., reagents spotted at a high density onto self-assembled monolayers (SAMs) for consistent and high recovery. The invention teaches, e.g., methods to make and use reagent array chips to screen for protease substrates. Identified substrates can, e.g., then be used to screen for modulators of the protease activity and to establish quantitative assays for the protease.

Abstract: Devices, methods and systems for low volume microarray processing are disclosed. The microarray devices preferably include a plurality of reactant sites on a reactant surface. The reactant sites include reactants that operate to capture one or more selected analytes that can then be detected based on an electromagnetic signal, e.g., fluorescence, that is emitted by each analyte in response to excitation energy incident on the microarray device. Mixing and/or distribution of the analyte sample over the reactant surface is accomplished by tilting the reactant surface such that the analyte sample flows over the reactant surface under the force of gravity. The tilting is performed such that a portion of the analyte sample accumulates in a bead along a first edge of the reactant surface. The reactant surface is then tilted in a different direction such that a portion of the analyte sample flows over the reactant surface and accumulates at a second edge.

Abstract: The present invention is directed to a flow through pipet for sample measurement. The pipet of the invention has a body defining an interior space for receiving a fluid. The drain line is provided to drain fluid above a drain line inlet, thereby establishing a repeatable upper fluid level in the body. A dispense valve on the lower end of the body selectively permit dispensing of the fluid from the body. A restriction member may be located in the interior space of the body for defining a passageway. The drain line inlet may communicate with the passageway to establish a smaller surface area for an upper surface of the fluid, thereby minimizing a variance in the fluid level. A vent line vents gas from the measuring chamber during filling of a fluid. The pipet of the invention is particularly suitable for use in an automated system due to the top fill feature, which eliminates the need for cycling back and forth between a fill vessel and a dispense vessel.

Abstract: The present invention provides a method for combining a fluid delivery system with an analysis system for performing immunological or other chemical of biological assays. The method comprises a miniature plastic fluidic cartridge containing a reaction chamber with a plurality of immobilized species, a capillary channel, and a pump structure along with an external linear actuator corresponding to the pump structure to provide force for the fluid delivery. The plastic fluidic cartridge can be configured in a variety of ways to affect the performance and complexity of the assay performed.

Abstract: A dispensing assembly for liquid droplets that includes a dispenser connected to a liquid carrying pipe which in turn is connected to a source of pressurized liquid. The dispenser has an elongated body member having a main bore connected to the liquid carrying pipe. At the other end, the main bore has a valve seat that is connected to a nozzle having a nozzle bore terminating in a dispensing tip. A valve boss of ferromagnetic material covered with a soft polymer is mounted in the main bore and has a cross-sectional area less than that of the main bore. A separate valve boss actuating coil assembly has upper and lower coils that are separate from the main body that can be unplugged from both coils and from the liquid carrying pipe. As such, the main body can be a disposable member.

Abstract: In a method for sampling a continuous liquid flow, the liquid flow is supplied to a surface along an input flow path. The liquid flow is sampled by forming a sample droplet from a portion of the liquid flow. The sample droplet is moved along an analysis flow path to a processing area of the surface, where the sample droplet is processed. Discrete sample droplets are formed and moved using an electrowetting technique. A binary mixing apparatus and method are also provided. The apparatus comprises an array of electrodes, an electronic controller communicating with the electrodes, a sample droplet supply area communicating with the array, and an additive droplet supply area communicating with the array. The electronic controller alternately energizes and de-energizes selected electrodes to carry out droplet-to-droplet binary mixing operations to obtain one or more droplets having a target mixing ratio.

Abstract: Liquids are transferred from a plurality of wells or depots having openings arranged in a selected format to one or more receptacles, by displacing liquid contained in each well so that a convex meniscus swells from the opening, and contacting the receptacle with the swollen meniscus to draw a portion of the liquid into the receptacle. An apparatus for carrying out the method includes a depot member having a plurality of wells having openings supported in a selected format, and a receiving member defining at least one receptacle and usually a plurality of receptacles in a corresponding or complementary format; means for displacing liquid contained within the wells toward and through the openings; and means for bringing at least one selected well opening into proximity with at least one selected receptacle.

Abstract: A device, process and system are provided for collecting and releasing a liquid sample, especially saliva. A defined saliva sample, i.e., a filtered, approximately homogeneously mixed saliva sample of a predetermined volume is made available in the simplest possible manner. A sampling tip (2) is provided made of a dimensionally stable and porous material, which is moved with its mouthpiece (4) in the mouth of a test subject for one to two minutes and takes up saliva based on the capillary action. A reagent liquid enters the pores of the sampling tip (2), mixes with the saliva there and is subsequently fed from a reagent depot by the action of pressure. The saliva and the reagent liquid are finally discharged as a droplet (40) in the filtered and mixed state, either into the cavity (10) of the sample collector or into a filter mixer.

Abstract: The invention relates to the efficient transport of a small volume of fluid, such as may be required by mass spectrometers and other devices configured to process and/or analyze small samples of biomolecular fluids. Such transport involves nozzleless acoustic ejection. In some instances, sample molecules contained in droplets of fluid are introduced from a reservoir into an ionization chamber of an analytical device. In other instances, sample molecules are introduced into a small capillary by directing focused acoustic radiation at a focal point near the surface of a fluid sample. In still other instances, acoustic ejection is used to form an array on a surface, wherein the features of the array are ionized for analysis. The invention may be used with microfluidic devices. Thus, the invention facilitates the processing and/or analysis of various types of samples, such as biomolecules having high molecular weights.

Abstract: There is provided a method and apparatus for aspirating a volume of liquid into a syringe from a sample of the liquid. A substantial portion of the liquid in the syringe is subsequently dispensed from the syringe and returned to the sample. Accordingly, a small portion of the aspirated liquid is retained in the syringe. One or more nanoliter volumes of the liquid retained in the syringe are then dispensed from the syringe to a container for further use or analysis. It will be understood, therefore, that the volume of the originally aspirated liquid is substantially larger than the volume of liquid dispensed for further use or analysis. The invention also includes a method and apparatus for aspirating and dispensing a plurality of liquids by using a plurality of syringes, and also can be used to dispense liquids onto microplates.

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: A sample tube of a sampling valve is moved up and down by a cylinder. When the sample tube is moved downward, a sample inlet opposes a stored sample, and the sample can be extracted. When the sample tube is moved upward, the sample inlet opposes a cleaning liquid path. Thus, cleaning liquid is fed into the cleaning liquid path from a cleaning liquid supply port of a cleaning pipe. The cleaning liquid flows within the sample tube from the sample inlet, and flows out from a sample discharge port. Thus, an entire interior of the sample tube can be cleaned. In a sample extracting device using the sampling valve, a state in which no air or impurities are mixed in the sample can always be maintained, such that stable extraction can be carried out.

Abstract: Microfluidic devices with porous membranes for molecular sieving, metering, and separation of analyte fluids. In one aspect, a microfluidic device includes a substrate having input and output microfluidic channel sections separated by a porous membrane formed integral to the substrate. In another aspect, the porous membrane may comprise a thin membrane that is sandwiched between upper and lower substrate members. The microfluidic device may include one or a plurality of porous membranes. In one embodiment, a plurality of porous membranes having increasingly smaller pores are disposed along portions of a microfluidic channel. In another embodiment, a cascading series of upper and lower channels are employed, wherein each upper/lower channel interface is separated by a respective porous membrane. In another aspect, a porous membrane is rotatably coupled to a substrate within a microfluidic channel via a MEMS actuator to enable the porous membrane to be positioned in filtering and pass-through positions.

Abstract: A single- or multi-well sample preparation apparatus and method for desalting, concentrating and depositing samples prior to further analysis such as by MALDI TOF mass spectrometry. The apparatus in accordance with an embodiment of the present invention includes a plurality of wells each in fluid communication with a respective outlet or drainage opening, optionally containing a three dimensional membrane structure preferably comprising a plurality of sorptive particles entrapped in a porous polymer matrix so as to form a device capable of carrying out solid phase extraction. The apparatus is designed to allow for direct spotting onto a MALDI target, thereby eliminating a transfer step. Also disclosed is a method of sample preparation, deposition and analysis using the apparatus of the present invention.

Abstract: A method for selectively depositing analysis-enhancing fluid on a sample surface is disclosed. The method involves providing a sample having a surface that exhibits variations in a surface characteristic that corresponds to desirability for receiving an analysis-enhancing fluid. Once a site on the sample surface is selected according to the surface characteristic at the site, focused radiation, typically acoustic radiation, is applied in a manner effective to eject a droplet of the analysis-enhancing fluid from a reservoir. As a result, the droplet is deposited on the sample surface at the selected site. Optionally, the sample at the selected site is analyzed. Systems for selectively depositing analysis-enhancing fluids are also disclosed.

Abstract: Devices and methods for integrated packaging, shipping, storage and precise dispensing of extremely small volumes of liquids such as aqueous solutions and compounds dissolved in organic solvents are disclosed. Devices of the invention include a sealed reservoir with an integrated metering tap. The tap includes a metering tube, which is translatable between a fill position inside the reservoir and an expel position outside the reservoir. The metering tube includes: (1) a tube end closure in a lower portion of the tube, (2) a port above the tube end closure, and (3) a piston in an upper portion of the tube. The piston is movable between a down position that seals the side port and an up position above the port. Movement of the piston from the up position to the down position can displace from 10 nanoliters to 20 microliters, e.g., from 20 nanoliters to 2 microliters, or 50 nanoliters to 500 nanoliters.