Abstract: A thermophoresis-resistant dilution apparatus for dilution of gas from an emission source, such as a combustion engine, for example a gasoline, diesel or natural gas engine. The apparatus is designed to simulate atmospheric dilution, mixing and cooling processes, enabling sampled emission gas and dilution air to thoroughly mix and cool to ambient temperature, allowing some volatile and semi-volatile gas-phase organics to nucleate, condense and coagulate to their usual aerosol phase. The apparatus is designed to resist thermophorectic forces acting on the particulate matter in the sampled emission gas, thereby preventing particulate matter losses. In addition, the apparatus evenly distributes the dilution air into the sampled gas for improved mixing.

Abstract: A disposable apparatus for use in blood testing and being adapted for simultaneous dilution of a blood sample into two different dilution ratios, said apparatus including a block-shaped housing having integrated therein a first and a second receptacle, one of which as a first blood sample receiver being adapted to receive a blood sample; a first and a second container, each containing a defined volume of a diluent; a valve including a valve body having three valve body channels extending therethrough and being positionable in three distinct positions, one of which putting the receptacles in simultaneous communication with a respective one of the containers through pairs of the channels; and displacers for displacing diluent and diluted sample through said channels between said containers and said receptacles.

Abstract: An apparatus and method for diluting and cooling that is extracted from high temperature and/or high pressure industrial processes. Through a feedback process, a specialized, CFD-modeled dilution cooler is employed along with real-time estimations of the point at which condensation will occur within the dilution cooler to define a level of dilution and diluted gas temperature that results in a gas that can be conveyed to standard gas analyzers that contains no condensed hydrocarbon compounds or condensed moisture.

Abstract: The present invention relates to a microfluidic device comprising a microchannel (2, 4) providing for solvent contact between an open microarea (MA) carrying a microvolume (1) of a solvent and a reservoir (3) for the solvent, said reservoir (3) and said microchannel (2, 4) being adapted so that solvent evaporated from said microarea (MA) is continuously replaced by solvent from the reservoir (3) through said microchannel (2, 4). It further relates to method for replacing solvents evaporating from a microvolume (1) of solvent placed in an open microarea (MA) of a microfluidic device, wherein replacement is continuously taking place via a microchannel (2, 4) that transports solvent to the microarea (MA) from a solvent reservoir (vessel) (3). The device and method are suitable for preventing the desiccation of samples.

Abstract: The present invention discloses an apparatus and method for rapid analysis of members of a combinatorial library. The apparatus includes a plurality of vessels for containing individual library members and a fluid handling system that apportions a test fluid about equally between each of the vessels. This allows for simultaneous screening of library members by detecting changes in test fluid following contact with individual library members. Fluid flow through each of the vessels is controlled using passive flow restrictors or active flow controllers to ensure that each library member contacts approximately the same amount of test fluid per unit time. The disclosed apparatus is especially useful for screening library members based on their ability to catalyze the conversion of fluid reactants.

Abstract: An analytical apparatus to monitor fluid systems has at least one extraction module having a raw-sample reservoir connected by input fluid conduit to individual ones of said fluid systems, to extract raw samples for analysis from said fluid systems, one or more modification modules comprising additive materials to modify the extracted raw samples prior to analysis, an analytical device to receive at least a portion of said raw samples in an ordered sequence, and to determine concentration of at least one constituent of said sample portion, fluid-handling apparatus for transferring fluid through the analytical apparatus, and a computerized control and management system to manage operations of component modules and devices, and to report analytical results.

Abstract: A flow-through monitor for detecting molecular contamination (MC) within a fluid flow. The monitor has a diffusion chamber having an inlet port and an outlet port, and a structure for supporting a fluid flow from the inlet port to the outlet port. The structure includes a flow gap causing a diffusion of molecular contaminants into the diffusion chamber, while substantially preventing, for a rate of the fluid flow above a predetermined magnitude, particulate contaminants within the fluid from entering the diffusion chamber. A SAW device detects molecular contamination interior to the diffusion chamber. Fluid input to the flow-through monitor may be diluted by a pure fluid for extended monitor life. A system for aggregate sampling connects an ensemble manifold upstream of the flow-through monitor. A system for triggered sampling connects a sample preconcentrator downstream of the flow-through monitor. A chemically selective membrane may be located between the flow gap and the SAW.

Abstract: An apparatus for synthesizing polymer chains includes a controller, a plurality of precision fit vials circularly arranged in multiple banks on a cartridge, a drain corresponding to each bank of vials, a chamber bowl, a plurality of valves for delivering reagents to selective vials, and a waste tube system for purging material from the vials. A purging operation can be selectively performed on one or more of the banks of vials. The multiple banks of valves provide an additional number of reagent choices while operating in a serial mode and faster reagent distribution while operating in a parallel mode. The plurality of vials are stored in the cartridge and are divided among individual banks wherein each bank of vials has a corresponding drain. There is at least one waste tube system for expelling the reagent solution from vials within a particular bank of vials when the waste tube system is coupled to the corresponding drain.

Abstract: The present invention provides improved methods and compositions for producing oocysts. The oocysts produced according to the invention find use in the manufacture of vaccines. In preferred embodiments, the present invention provides methods and compositions for the production of Eimeria oocysts. Vaccines containing Eimeria oocysts, sporocysts and/or sporozoites produced according to the present invention may be used to immunize birds against coccidiosis either in ovo or post hatch.

Abstract: Parallel flow reaction systems comprising four or more reaction channels are disclosed. Distribution systems, and parallel flow reaction systems comprising such distribution systems are also disclosed. Specifically, the distribution systems comprise a feed-composition subsystem for providing a different feed composition to each of the four or more reactors. In preferred embodiments, the feed composition subsystem comprises at least one set of four or more feed-component flow restrictors, each of the four or more feed-component flow restrictors having a flow resistance that varies relative to other flow restrictors in the set.

Abstract: The present invention relates to conducting a plurality of chemical reactions in a system including an apparatus which provides energy for the chemical reactions, such as chemical reactions in organic synthesis, where a particular advantage is the use of predetermined reaction parameters corresponding to similar chemical reactions. The present invention also relates to a system for performing said method and to corresponding kits and software. The system comprises an apparatus which can provide energy for the chemical reactions, said apparatus comprising a reaction cavity and a liquid handler, and a parameter selecting unit having a user interface means, a search unit means, apparatus control unit means, and storage means for carrying a database.

Abstract: A chemical for dissolving a sample taken from the semiconductor device fabrication equipment for analyzing the contaminants attached thereon, and a method of analyzing the contaminants thereby. The chemical composition is made of equal ports of sulfuric acid, hydrogen fluoride, and nitric acid. The method includes a) immersing a sample taken from semiconductor device fabrication equipment in the chemical composition; b) dissolving the sample in the chemical composition; c) cooling the dissolved sample; d) diluting the dissolved sample with deionized water and e) analyzing the diluted sample using either Atomic Absorption Spectrometer or by Atomic Emission Spectroscopy.

Abstract: Methods and devices are provided for controlling a fluid flow over a sensing surface within a flow cell The methods employ laminar flow techniques to position a fluid flow over one or more discrete sensing areas on the sensing surface of the flow cell. Such methods permit selective sensitization of the discrete sensing areas, and provide selective contact of the discrete sensing areas with a sample fluid flow. Immobilization of a ligand upon the discrete sensing area, followed by selective contact with an analyte contained within the sample fluid flow, allows analysis by a wide variety of techniques. Sensitized sensing surfaces, and sensor devices and systems are also provided.

Abstract: An apparatus for continuous on-line measurement of chemical composition of aerosol particles with a fast time resolution is provided. The apparatus includes an enhanced particle size magnifier for producing activated aerosol particles and an enhanced collection device which collects the activated aerosol particles into a liquid stream for quantitative analysis by analytical means. Methods for on-line measurement of chemical composition of aerosol particles are also provided, the method including exposing aerosol carrying sample air to hot saturated steam thereby forming activated aerosol particles; collecting the activated aerosol particles by a collection device for delivery as a jet stream onto an impaction surface; and flushing off the activated aerosol particles from the impaction surface into a liquid stream for delivery of the collected liquid stream to an analytical instrument for quantitative measurement.

Abstract: A method is provided for performing array microcrystallizations to determine suitable crystallization conditions for a molecule, the method comprising: forming an array of microcrystallizations, each microcrystallization comprising a drop comprising a mother liquor solution whose composition varies within the array and a molecule to be crystallized, the drop having a volume of less than 1 microliter; storing the array of microcrystallizations under conditions suitable for molecule crystals to form in the drops in the array; and detecting molecule crystal formation in the drops by taking images of the drops.

Abstract: A multiwell plate for microarraying comprising a self-sealing lower membrane and optionally also a self-sealing upper membrane. Spotting is performed by pushing a pin down through the liquid and then on to pierce the self-sealing lower membrane. A slide having an upper spotting surface is arranged under the well plate. The liquid sample forced through the lower membrane by the pin tip can thus be deposited directly onto the spotting surface. The pin is then withdrawn upwards through the lower membrane, which automatically reseals preventing further loss of liquid. The optional resealable upper membrane also prevents loss of sample liquid by evaporation and spillage. By contrast to the prior art, there is the major advantage that the pin head does not have to traverse between the well plate and slide to collect sample liquid, thus dramatically increasing operational speed for an automated microarraying apparatus employing the multiwell plate. Excellent spot reproducibility is also observed.

Abstract: The present invention is directed to a method of preparing a biological sample for quantification which includes an element to be quantified. A volume of biological sample is collected without quantifying the volume thereof to mix with a specified volume of an aqueous solution. Absorptivity of an indicating material in the aqueous solution is measured. Absorptivity of the indicating material in the collected biological sample mixed with the specified volume of the aqueous solution is measured. Next, a dilution ratio of the biological sample is calculated using the absorptivity of the indicating material in the specified volume of the aqueous solution and the absorptivity of the indicating material in the biological sample mixed with the specified volume of the aqueous solution.

Abstract: An interconnection support for plate-like microcomponents (1) has a support rail (2) which is attached to a support plate (3). An insertion slot (4) for the support rail (2) accommodates an insertion edge (5) of a plate-like microcomponent (1). Like connections (10, 10a), which can be connected to associated connections (11) in an outside (1a) of the plate-like microcomponent (1), are provided in at least one side wall (9) of the insertion slot (4) of the support rail (2).

Abstract: A dissolution test sample holder for testing topical formulations for dermal and/or transdermal drug delivery is disclosed. The holder has a cylinder tubular body with an end cap removably attached to one end. The end cap has a peripheral wall which frictionally engages the body to hold the end cap in place. A flange extends perpendicularly from the peripheral wall inwardly defining an aperture in the end cap and providing a support surface for a membrane held within the end cap. A ring is positioned within the end cap on the membrane, the membrane being sandwiched between the ring and the support surface. The ring protects the membrane by preventing contact between it and the body and provides a volume for holding the test sample in contact with the membrane.

Abstract: Modular microfluidic systems includes a plurality of microfluidic modules, each capable of performing fluidic operations including, but not limited to, filtering, splitting, regulating pressure, mixing, metering, reacting, diverting, heating, cooling, and condensing are provided. The microfluidic modules are polymeric, stencil-based structures adapted to be coupled in sequence for performing biological or chemical synthesis, including, but not limited to, chemical and biological syntheses of organic, polymer, inorganic, oligonucleotide, peptide, protein, bacteria, and enzymatic products.

Abstract: A system and method for dispensing a sample using a self-dispensing system including a sample storage device, a dispensing mechanism, and a driving mechanism for driving the dispensing mechanism. The dispensing mechanism is formed as part of and is in dispensing communication with the sample storage device. Preferably the dispensing mechanism is a positive displacement type dispensing mechanism and includes an inlet valve, an actuator, and an outlet valve. The driving mechanism may be positioned internal or external to the dispensing mechanism and drives the dispensing mechanism thereby inducing a flow of a measured quantity of the sample into or out of the storage device. Preferably, the dispensing mechanism is relatively inexpensive and is disposable.

Abstract: Analyzing a plurality of fluid specimens with a single analyzing instrument comprising introducing different combinations of specimens into a homogenizing volume to create a homogenized specimen and with a programmed digital computer mathematically processing the recorded results to produce analyses corresponding to individual fluid specimens.

Abstract: A silicon nitride cuvette window for a microsampling device and method of construction are provided. The sample to be analyzed is drawn into the cuvette of the microsampling device. The silicon nitride window permits optical measurements to be made on analytes contained within the cuvette.

Abstract: Methods for manufacturing and using an apparatus for manipulating and analyzing a large number of microscopic samples of a liquid or materials, including cells, in liquid suspension. Parallel through-holes are formed in a platen and loaded with a liquid. Loading may be performed in such a way as to create a gradient, with respect to the position of the through-holes, of the concentration of a particular substance or of another quantity. Mixing of the contents of through-holes may be obtained by bringing filled microwell arrays into contact with each other with registration of individual through-holes.

Abstract: A fluid treatment device is disclosed for mixing first and second fluids. The first fluid may be a treatment liquid that is contained in a container and that is used to change a property, such as the pH, density or ionic strength, of the second fluid. In some illustrative embodiments, the fluid treatment device is used to create an effluent by adding a buffer material and/or a matrix material to an analyte for subsequent MALDI MS analysis of the effluent. A mixing space is defined in a container between ends of first and second conduits. In some embodiments, a junction member couples together the ends of the first and second conduits. The junction member has a main passage that receives the ends of the first and second conduits. The junction member has at least one opening that provides fluid communication between an interior region of the container and the mixing space.

Abstract: A method for dispensing droplets of a liquid to a microsystem in the form of a disc comprising a target area (TA0I) in its surface, said disc preferably being a microfluidic disc comprising a microchannel structure with an inlet port that is a target area (TA0I). The method is characterized by comprising the steps of: i) providing (1) said disc which has a triggering mark, and (2) a dispenser arrangement comprising: a) a spinner for rotating the disc around its axis, b) a drop dispenser permitting dispensation of droplets to inlet port I, c) a fixed trigger position outside the disc, and d) a controller which is capable of triggering the dispensation of a droplet into (TA0I) as a function of the triggering mark passing the trigger position, ii) placing the disc in the spinner and programming the controller with values for dispensing parameters that will give dispensation of the droplets to TA0I, iii) dispensing the droplets. The invention also comprises the dispenser arrangement as such.

Abstract: The present invention recognizes that separation of components of a sample facilitate, and are often necessary for, sample analysis. Dielectrophoretic separation provides an efficient, reliable, nondisruptive, and automatable method for the separation of moieties in a sample based on their dielectric properties. The present invention provides compositions and methods for enhancing the dielectrophoretic separation of one or more moieties in a sample. A first aspect of the present invention is a solution that when mixed with a sample, modifies at least one dielectric property of one or more components of the sample and has a conductivity such that one or more moieties of the sample can be separated using dielectrophoresis. Such solutions can be used in the analysis of samples on chips, and can be used in methods that use binding partners, including microparticles that can be translocated by dielectrophoretic forces, traveling-wave dielectrophoretic forces or magnetic forces.

Abstract: Flow rates in a microfluidic device are modulated after performing serial dilutions by flow reduction channels that draw fluid from the main channel, thus reducing the flow rate. The reduction in flow rate and/or use of smaller dimension channels allow reduced reagent consumption. In addition, multiple flow reduction channels are used for multiple concentration measurements and for performing multiple assays simultaneously on a single sample. Also included are microfluidic devices and integrated systems for performing assays using serial dilutions, single pressure sources, multiple concentration measurements, and reduced reagent consumption. Devices comprising flow reduction channels are also used to suppress pressure perturbations from spontaneous injection.

Abstract: A new method of producing liposomes is described using an in-line mixing system. The liposomes produced by this method find utility in numerous therapeutic applications.

Abstract: a method for separating particulate matter from a fluid, using apparatus which includes a container and cover, a filter assembly positioned in a housing atop the cover and suitable for collecting particulate matter in the fluid on a collection surface, and a dispersing element fixed relative to the cover. The cover has a portion that is fixed in a first position and freely rotatable in a second position. The specimen is placed in the container, and a mixer apparatus rotates the container in relation to the cover to disperse the particulate matter throughout the fluid. Upon deactivation of the mixer apparatus, a fluid sample including dispersed particulate matter is drawn through the filter assembly to capture a substantially uniform layer of particulate matter on the collection surface. The housing is then opened to expose the layer of particulate matter, which is then transferred to a microscope slide.

Abstract: Two dimensional COSY magnetic resonance spectroscopy of human stool can be used in a non-invasive method of detecting the presence of colorectal cancer. The spectrum of a patient's stool is compared with that of stool from non-cancerous subjects, observed differences in spectra being indicative of cancer.

Abstract: A method of assaying a specimen, comprising: preparing (i) a specimen, (ii) a liquid cell in which a liquid used for assaying a component in the specimen, such as a liquid reagent or a liquid diluent, is to be contained, and (iii) a mixing cell wherein the specimen and the liquid are mixed; supplying a liquid reagent into the liquid cell in an amount exceeding the amount required in the assay; pipetting a portion of the specimen and a portion of the liquid into the mixing cell using a pipetting tip; and washing the pipetting tip with the liquid remaining in the liquid cell.

Abstract: A method of speciated isotope dilution mass spectrometry (SIDMS) which will permit determination of concentrations of one or more species from a sample even if the sample has been subjected to species conversion prior to species separation or degradation or incomplete separation exists. At least one predetermined stable isotope is spiked to convert the stable isotope to a speciated enriched isotope corresponding to the specie or species to be measured in the sample. The sample containing the species to be measured is spiked and the isotopic spiked specie and species to be measured are equilibrated. The species are separated from the sample and an isotope ratio determination for each specie to be measured is made. The species concentrations are then mathematically deconvoluted while correcting for species conversion and/or incomplete separation. The method may be employed to validate other methods. The method may also be employed in the preparation and analysis of speciated standard reference materials.

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. Rings are optionally disposed between the cover layer and the body structure and circumferentially around pairs of aligned apertures and ports. The devices also optionally include conductive coatings and membranes. The invention additionally provides methods of controlling the delivery of a composition of material into a microfluidic device.

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 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: A diluting solution moving unit moves a diluting solution in forward and reverse directions in a flow path. A probe is connected to the flow path through a T-junction and sucks a sample. A sample syringe is connected to the flow path through a T-junction. A control unit performs controlling so that the diluting solution moving unit is driven to move the diluting solution in the flow path and the sample syringe is driven to make the probe suck the sample into the flow path to thereby dilute the sucked sample with the diluting solution and further driven so that the sample solution diluted with the diluting solution is delivered from the probe into any one of reaction containers. There can be provided a dispensing apparatus in which dilution of the sample is made in a short time and in which the accuracy of the diluting rate is improved.

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: An automated device that couples a pair of differently sized sample loops with a syringe pump and a source of degassed water. A fluid sample is mounted at an inlet port and delivered to the sample loops. A selected sample from the sample loops is diluted in the syringe pump with the degassed water and fed to a flow through detector for analysis. The sample inlet is also directly connected to the syringe pump to selectively perform analysis without dilution. The device is airtight and used to detect oxygen-sensitive species, such as dithionite in groundwater following a remedial injection to treat soil contamination.

Abstract: A concentration detection method and a concentration detection apparatus, and an agent diluting preparation apparatus capable of accurately estimating the concentration of a solution without the need of strict temperature control, and of estimating the concentration of the solution in real time, and further of cost reduction of diluting and preparing an agent and of simplification of diluting and preparing work are provided herein.

Abstract: A chemical collection assembly and a method for using the assembly such that a chemical-mechanical polishing (CMP) pad used in the manufacture of semiconductor wafers can be assessed for cleanliness. The method involves delivering solvent from the assembly's reservoir to an enclosed volume over the CMP pad. The solvent then brings contaminants imbedded on the CMP pad into solution. This solution is then drawn back up from the enclosed volume wherefrom a sample of the solution can be taken. That sample is then analyzed for the level of contaminants present therein, and the analysis is compared to a pre-determined level of cleanliness to determine whether the CMP pad should or should not continue to be used for semiconductor wafer manufacturing.

Abstract: A device for producing microscopic arrays of molecules is provided, the device comprising a plurality of inverted cavities containing solutions, a substrate adapted to be received by the cavities for extracting the solutions, a substrate for depositing the extracted solutions onto a location on a matrix; and a quality control monitoring system for verifying that the solutions are deposited onto the location on the matrix. A process for producing an array of molecules also is provided, the process comprising providing a plurality of inverted solution cavities, wherein each cavity contains a solution; extracting each solution from its respective inverted cavity; loading each solution at a predetermined position in an array; and verifying that each solution is loaded onto its respective position in the array.

Abstract: Devices and methods are provided for collecting a sample, diluting the sample in a buffer, and dispensing it for analysis by a method of choice. The devices comprise a dropper top dispensing component having a housing and an elongated swab member inserted in the dropper top and having a swab end with an absorbent for collecting a sample. Also included is a vial that contains a buffer and is attachable to the dropper top so as to immerse the absorbent in the buffer after the absorbent has been used to collect the sample. One embodiment incorporates a dispensing chamber within the dropper top for controlling the amount of sample dispensed from the device, so the device is capable of dispensing sample in drop-sized increments.

Abstract: A system for collecting a whole blood sample includes a fill port (32), a metering chamber (72), a gasket or seal (16) and a reservoir (74). The gasket or seal (16) is positioned to a fill position, and a sample of whole blood is received in the metering chamber (72) until the metering chamber (72) is full. Then the seal (16) is moved to a closed position, thereby moving blood from the metering chamber (72) to the reservoir (74) and also sealing the reservoir (74). The seal (16), metering chamber (72) and fill port (32) together define a passageway at least a portion of which is coated with an anticoagulant. A diluting liquid contained in the reservoir (74) is mixed with the whole blood to dilute and stabilize the whole blood in the reservoir (74) for later analysis of one or more selected blood components.

Abstract: Methods and devices for inducing high bulk hydrodynamic resistance and/or for inducing low electrical resistance in microscale systems including bulk viscosity enhancers, surfactants, and electrolytes. High bulk hydrodynamic resistance is optionally utilized to regulate the effects of spontaneous injection and/or dispersion. Induced high hydrodynamic resistance in conjunction with induced low electrical resistance are optionally utilized to provide and regulate electrical fields within microfluidic devices. Integrated systems incorporating the methods of the invention are also provided.

Abstract: The present invention provides a process for forming electrical contacts to a molecular layer in a nanoscale device, the nanoscale device, and a method of manufacturing an integrated circuit comprise such devices. The process includes coating a surface of a stamp with a metal layer and forming an attached layer of anchored molecules by coupling first ends of the anchored molecules to a conductive or semiconductive substrate. The process also includes placing the metal layer in contact with the attached layer of anchored molecules such that the metal layer chemically bonds to free ends of the anchored molecules. The resulting devices produced have superior reliability as compared to conventional prepared devices.

Abstract: A device and a method for diluting a sample are disclosed. A sample is first diluted by a porous tube type diluter configuration. Then the diluted flow is further diluted by a ejector type diluter configuration. Further a heat exchange based on serrature heat exchange elements inside said porous tube type diluter configuration is disclosed.

Abstract: A method involving the automatic, online dilution of polymer and/or colloid solutions, such that, when the diluted polymer stream flows through suitable detectors, non-equilibrium processes, such as polymerization, degradation and aggregation, can be monitored. The dilution involves a reacting or stock solution of polymer and/or colloid, and at least one solvent. The online dilution technique can also be used to assess the effects of solvent quality and other solutes on polymer/colloid characteristics and reactions, and also permits equilibrium characterization of polymers/colloids by making a single stock solution of the polymer/colloid.

Abstract: A device and method for filtering a biologically derived sample and for mixing the sample with a reagent, comprising a fluid container defining a reservoir compartment and including a container outlet, a filter and a fluid flow-through matrix disposed in a flow path between the reservoir compartment and the container outlet. Water-soluble, dried reagent is retained on the matrix. Means is provided for urging sample in an aqueous liquid in the reservoir compartment through the filter and matrix and out the container outlet. Pressure is applied to the sample in an aqueous liquid in the reservoir compartment to cause the sample to flow in liquid through the filter and matrix and out of the container for analysis.

Abstract: A novel reagent system for use with automated and semi-automated hematology analyzers including an essentially isotonic blood diluting reagent, a blood cell lysing and hemoglobin conversion reagent, and a second lysing reagent for differentiating white blood cells into classes by size and functional characteristics. The diluent reagent enhances properties for counting and sizing blood specimens, while stabilizing cellular volume and cellular integrity for many hours. The blood cell lysing reagent removes red blood cells and enables subsequent enumeration of white blood cells and simultaneous determination of hemoglobin without use of the toxic cyanide anion. The third lysing reagent and a companion quenching differentiates blood cells into classes by size and functional characteristics, based on d.c. impedance volume, conductivity/opacity and light scatter measurements. The companion quenching reagent adjusts pH and conductivity of the final measurement solution to match the analyzer system requirements.