Abstract: The present invention is directed toward monitoring a thermally driven gas evolving chemical reaction with an acoustic apparatus. Signals from the acoustic apparatus are used to control a heater to prevent a run-away condition. A digestion module in combination with a robotic arm further automate physical handling of sample material reaction vessels. The invention is especially useful for carrying out sample procedures defined in EPA Methods SW-846.

Abstract: A method for fractionating and sequencing DNA via affinity interaction is provided comprising contacting cleaved DNA to a first array of oligonucleotide molecules to facilitate hybridization between said cleaved DNA and the molecules; extracting the hybridized DNA from the molecules; contacting said extracted hybridized DNA with a second array of oligonucleotide molecules, wherein the oligonucleotide molecules in the second array have specified base sequences that are complementary to said extracted hybridized DNA; and attaching labeled DNA to the second array of oligonucleotide molecules, wherein the labeled re-hybridized DNA have sequences that are complementary to the oligomers.

Abstract: This invention relates to a novel analytical device for collecting, analyzing and storing of biological samples and, more specifically, to an analytical device used in the analysis of biological fluids such as urine.

Abstract: The present invention describes a multiple sample container for use in a method and apparatus for detecting microorganisms in a culture container. The container includes a block having a plurality of through holes for dividing the sample into a plurality of partial samples. Each partial sample has its own head space and its own sensor. The spacial array of partial samples is read out by a CCD camera and split into partial sample to generate a spacial array that results in a substantial reduction in the time to detection.

Abstract: Method and apparatus for enabling resuspension wash and magnetic localization of sample components bound to particles with magnetic properties in reaction vessels during separation and wash for enhanced chemiluminescent signal generation in biomedical assays. The assays involve moving reaction vessels past magnetic arrays that partially localized the particles prior to passing a gap where washing occurs, with or without resuspension, after separating out the unbound components and liquid. The band of particles is further localized by a focusing magnet at the end of the array prior to dosing the vessel with acid for chemiluminescent purposes. A block of soft magnetic material is employed in place of a magnet in the gap to minimize magnetic strength at the gap. Trimmed magnets adjacent the gap cause left, then right, particle shifting that localizes the magnetizable particles. The gap enables improved resuspension by wash, whereas the localized particles enable more efficient resuspension by reagent.

Abstract: An immunoassay plate for an immune complex transfer immunoassay, comprising a well type solid phase and a dip stick type solid phase which can be inserted into said well type solid phase, wherein the dip stick type solid phase is coated with either substance (A) or (B) to be mentioned below and the well type solid phase is coated with the other, remaining substance, and these solid phases are used as the two solid phases to be used for an immune complex transfer immunoassay:(A): a substance having a reactive group which specifically binds to a functional group previously introduced onto a substance, which specifically forms an immune complex with a test substance(B): a substance having a reactive group capable of specifically binding to the test substance in the immune complex, a substance which specifically forms an immune complex with the test substance, or a functional group conjugated in advance with said substance, provided that the moiety which binds to the reactive group of (A) does not bind to the rea

Abstract: A deepithelialized skin cell diffusion system which can be used to select topical gel and cream formulations containing human other wound healing promoters such as plasma fibronectin. The formulations provide slow release and increased contact time of fibronectin or other wound healing promoters to the wound site leading to its effective absorption.

Abstract: An optochemical fluorescence sensor with a biorecognitive layer for measuring the concentration of one or more analytes in a sample is provided with at least one island layer which is applied on a sensor substrate. The islands of the island layer are in the form of electrically-conductive material and have a diameter of less than 300 nm, the biorecognitive layer being directly applied on the island layer or bound via a spacer film. In addition, an analyte-specific fluorescent compound is provided which may be added to the sample or is provided in the sensor itself. The biorecognitive layer can bind the analyte to be measured directly or by means of analyte-binding molecules, the originally low quantum yield of the fluorescent compound increasing strongly in the vicinity of the island layer.

Abstract: Disclosed are devices for detecting the presence of a preselected analyte in a fluid sample. The devices comprise a substrate microfabricated to define a sample inlet port, and a mesoscale flow system that includes a sample flow channel extending from the inlet port. The mesoscale flow system further includes an analyte detection region in fluid communication with the flow channel comprised of a binding moiety for specifically binding the analyte. The detection region is constructed with a mesoscale dimension sufficiently small to enhance binding of the binding moiety and the analyte. The binding moiety may be immobilized in the detection region. The mesoscale detection systems of the invention may be used in a wide range of applications, including the detection of cells or macromolecules, or for monitoring reactions or cell culture growth.

Abstract: The present invention provides a method of performing an immunological assay separately and in parallel for each of at least a first sample containing or prospectively containing a first binding moiety, which can be an antigen or an antibody, and a second sample containing or prospectively containing the first binding moiety, the method comprising: placing the first sample and the second sample into an array comprising a solid substrate, a plurality of wells and channels, wherein at least one channel is a crossover channel formed in the upper surface of the substrate and is situated above another channel formed in the lower surface of the substrate, thereby forming crossovers comprising crossing but non-intersecting channels; moving said first sample into a first well containing a second binding moiety, which can be an antigen or an antibody, that binds to the first binding moiety, wherein the second binding moiety is bound to the walls of the first well; moving said second sample into a second well containin

Abstract: For the purpose of reversible optical indication of the pH of a sample, a hydrophilic accommodating layer is disposed on a hydrophobic mechanically stable support element, which layer contains the indicator dye proper in an immobilized form. This provides a sensor membrane which can be fabricated in a simple manner and is cost-effective, which has a rapid response time and can also be fabricated as a mass product to be used only once.

Abstract: A treatment apparatus for analyzing the impurities in silicic material with high precision, includes a container having an inner space in which at least one analysis sample container and a sample decomposing solution are accommodated. The container is divided into a lid body and a lower body, each of the lid body and the lower body being opened at the division surface side thereof to form an open end and being closed at the surface side opposite to the division surface side to form a close end thereof. The inner peripheral surface of the open end of the lower body is formed in a stepwise shape so that the analysis sample container is disposed to be spaced from the surface of the decomposing solution which is stocked in the lower body, and the inner peripheral surfaces of the lid body and the lower body are smoothly continuously threadily engaged with each other through abutment faces thereof to keep the container in an appropriate hermetic level.

Abstract: An improved microfabricated apparatus for conducting a multiplicity of individual and simultaneous binding reactions is described. The apparatus comprises a substrate on which are located discrete and isolated sites for binding reactions. The apparatus is characterized by discrete and isolated regions that extend through said substrate and terminate on a second surface thereof such that when a test sample is allowed to the substrate, it is capable of penetrating through each such region during the course of said binding reaction. The apparatus is especially useful for sequencing by hybridization of DNA molecules.

Abstract: A method and apparatus for performing a chemiluminescent assay are disclosed. A test sample or multiple test samples is or are deposited on a supporting matrix and chemiluminescence of the sample(s) is effectuated. Low energy chemiluminescence emitted during chemiluminescence is removed by a light attenuation optical filter. Chemiluminescence is detected from the filtered light using a light detector means and chemiluminescence is counted using a chemiluminescence counter coupled to the light detector means.

Abstract: A novel enzyme sandwich immunoassay cassette comprising a microporous membrane support having coated thereon:(a) a conductive metal layer; and(b) a capture antibody layer over the conductive metal layer.

Abstract: Methods for determining the presence of a ligand in a sample suspected to contain the ligand are provided, along with apparatus suitable for performing the methods. The methods depend upon a color visualization indicating the ligand's presence or absence in the sample. Preferred methods comprise contacting the sample with colored particles which bear on their surface a receptor specific for the ligand, passing the sample/particle mixture through a filter, and then analyzing the color of the filtrate. The presence of ligand in the sample is established where the color of the filtrate is substantially different from the color of the receptor-bearing particles.

Abstract: A chemical sensor includes a patterned layer having discrete sections, a -dimensional detector array, and a two-dimensional lens array that focuses an optical signal from the patterned layer onto the two dimensional detector array. Typically, the two-dimensional detector array is a charge-coupled device array and the lens array is a graded index of refraction lens array. The chemical sensor maintains good resolution throughout its field of view.

Abstract: Sets and libraries of sets of polypeptides that are related in sequence to melittin are disclosed that have antimicrobial, hemolytic and hydrolytically catalytic activities, as are processes for making and using the same. A contemplated set is a mixture of equimolar amounts of a polypeptide of SEQ ID NO:2, and more preferably SEQ ID NO:3.

Abstract: An optical measurement apparatus includes a reaction vessel 2 which is formed in one body with a slab-type optical waveguide 1, and the apparatus adds fine-grains or water soluble dye for absorbing a fluorescent light which is radiated from fluorescent dye, and/or an exciting light so that stray light due to reagent is reduced and the S/N ratio of the optical measurement is improved.

Abstract: The invention features devices that each consist of a tube containing a linear array of specific binding elements that each have capture probes specific for a target analyte linked thereto. The devices of the invention can be used in methods for detecting target analytes in samples.

Abstract: A method and device is described for direct removal of heparin from whole blood during extracorporeal therapy. In clinical situations where the blood is heparinized to prevent clotting in the extracorporeal circuit containing e.g., a hemodialysis cartridge or a heart-lung machine, it would be desirable to eliminate the systemic heparinization of the patients. The extracorporeal circuit contains a device having antithrombin III immobilized and inserted between the outlet port of the primary extracorporeal device, such as the hemodialysis cartridge or heart-lung machine and the patient. When the heparinized blood comes in contact with the immobilized antithrombin III, heparin is removed and the reperfused blood is substantially free of heparin. The advantage of the system lies in the fact that heparin is removed from the blood rather than neutralized. This helps overcome the adverse reactions and side effects associated with the use of heparin anticoagulation.

Abstract: A device and method for its use in diagnostic assays are provided. The device comprises at least one assay path, where an assay path includes a main flow path and at least one side reagent channel. The main flow path begins at a sample addition port, continues through a main reagent area into an incubation area and ends in a waste area. In fluid communication with the main flow path is at least one side reagent channel that begins at a liquid addition port, continues through a side reagent area and ends in said main channel at a region between the main reagent and waste areas, usually upstream from the incubation area. Agitation means may be included in at least one of the main and side reagent areas and/or the incubation area. At least one fluid interruption means located at various positions along the main and side reagent channels upstream from the incubation area provide for control over reagent interaction and fluid flow through the device.

Abstract: A test kit and method for the highly sensitive detection of specific analytes in a sample is provided. The presence of the analyte in the sample results in a decrease in the concentration of a growth inhibiting substance leading to proliferation of cells in the region of the analyte. The presence or absence of the analyte is determined by detecting the presence of increased numbers of cells. Assay sensitivity is accounted for by the exponential amplification of cell number that occurs during cell proliferation in the presence of analyte.

Abstract: A test device for detecting or determining an analyte in a test solution includes an absorbent material having separate contact, competitive binding, and measurement portions. The contact portion is positioned for contact with and uptake of the test solution. The competitive binding portion has a binding material for the analyte non-diffusively bound thereto. The measurement portion has a receptor for the analyte and marker-encapsulating liposomes non-diffusively bound thereto. In a method for using the test device, a solution containing the analyte and the analyte-liposome conjugate is allowed to traverse the absorbent material from the contact portion through the competitive binding portion and on through the measurement portion of the absorbent material. The amount of marker in the measurement portion of the absorbent material, following traversal by the test solution, is then determined as a measure of the analyte in the sample.

Abstract: A self contained glucose sensor is provided that generally comprises a strip type glucose sensing electrode having an active surface comprising an organic conducting redox salt dispersed in a polymeric membrane, with the membrane coating a conductive strip and a strip type Ag/AgCl reference electrode having its active surface separated from physical contact with the strip type glucose sensor and a carrier strip of water absorbent paper or film containing an enzyme system and an oxidizable dye. The water absorbent carrier strip is in simultaneous contact with both the active surface of the strip type glucose electrode and the active surface of the strip type reference electrode. When an aqueous solution containing glucose is brought in contact with the carrier strip containing the enzyme system an electrical potential, proportional to the concentration of glucose in the solution, is created which can be detected by an electrometer or other suitable device.

Abstract: A method and apparatus for immunoassays utilizes an improved collection technique of fluorescence induced emissions at the solid phase/liquid phase interface from surface plasmon resonance sensing devices. In a preferred embodiment, a solid phase substrate is coated with a thin film of a conducting material on which a first specific binding partner is directly or indirectly immobilized. The coated solid phase substrate is incubated with a liquid component comprised of a biological sample containing a specific ligand or analyte and a fluorescent labeled second specific binding partner in the case of immunometric assays, or a fluorescent labeled ligand or analog thereof in the case of competitive assays.

Abstract: A bead dispenser device, and a system comprising a plurality of same, useful for supplying, one at a time, beads for heterogenous immunoassay, including a track capable of storing and feeding a plurality of substantially spherical beads by effect of gravity to a lower track end, where the track is sealingly housed within an enclosure having a base including upper and lower sections defining a plunger chamber, and a bead chamber defined in the upper section communicating with the lower track end and the bead chamber being offset along the plunger chamber relative to a bead exit opening in the lower section, with a plunger sealingly provided in the plunger chamber capable of horizontal reciprocal movement within the plunger chamber, the plunger having a throughhole defining another bead chamber normally aligned with the first-mentioned bead chamber at the lower track end and with a plunger portion concurrently blocking the exit opening via a horizontal biasing device acting on the plunger, wherein when opposing

Abstract: A particularly efficient design for a nonbibulous lateral flow one step assay for an analyte in a biological sample is disclosed. In the improved device of the invention, three zones which are in nonbibulous lateral flow contact are employed: a sample receiving zone, a labeling zone, and a capture zone. The sample containing analyte is carried through the labeling zone and interacts with an assay label comprising visible moieties, preferably particles, which are coupled to specific binding reagent for analyte or to a competitor with analyte for a capture reagent. The flow continues into the capture zone where the visible moieties to which analyte or competitor are coupled are captured. Excess fluid is absorbed into an absorbent zone in contact with the capture zone. A positive result is obtained by visualizing the visible moieties in the capture zone.

Abstract: Improved devices for collecting and analyzing samples of aqueous solutions, body fluids, sewage or fecal matter to be used in detecting microbes and microbial byproducts. A device in accordance with the invention comprises a body including an internal channel having an entryway, a solute chamber connected to the entryway, a solute-adding mechanism operatively connected to the solute chamber, a window in the body that allows viewing of a portion of the channel, and an aperture in the body that opens to the channel; a bendable tang connected to the body; and a sample collection unit attached to the tang.

Abstract: A particularly efficient design for a nonbibulous lateral flow one step assay for an analyte in a biological sample is disclosed. In the improved device of the invention, three zones which are in nonbibulous lateral flow contact are employed: a sample receiving zone, a labeling zone, and a capture zone. The sample containing analyte is carried through the labeling zone and interacts with an assay label comprising visible moieties, preferably particles, which are coupled to specific binding reagent for analyte or to a competitor with analyte for a capture reagent. The flow continues into the capture zone where the visible moieties to which analyte or competitor are coupled are captured. Excess fluid is absorbed into an absorbent zone in contact with the capture zone. A positive result is obtained by visualizing the visible moieties in the capture zone.

Abstract: A test device for detecting or quantifying an analyte in a test sample includes an absorbent material having separate contact and measurement portions. The contact portion is positioned at or proximate to a first end of the absorbent material. The measurement portion has a receptor for a conjugate of an analyte analog and marker-encapsulating liposomes. In a method for using the test device, a binding material specific for the analyte is combined with the liposome-analyte analog conjugate and the test sample to form a test mixture. The mixture is incubated for a time sufficient to permit competition between any analyte present and the conjugate for the binding material. Following incubation, the mixture is allowed to traverse the absorbent material from the contact portion through the measurement portion of the absorbent material.

Abstract: A diagnostic test, and a device for conducting the test, for assessing whether patient chest pain is cardiac in origin and for differentiating between unstable angina and myocardial infarction as a cause of patient chest pain is described. The diagnostic test comprises simultaneously detecting at least three selected cardiac markers with the use of at least three different monoclonal or polyclonal antibody pairs, each member of which is complementary to a different marker, which is released by heart muscle at varying stages after the onset of chest pain and is indicative of the cause of the chest pain.

Abstract: Devices and methods are provided to facilitate the rapid, accurate analysis of a sample having cells characterized by their motility. The devices feature a solid substrate microfabricated to define a flow system including one or more ports or chambers, connected by elongate channels of various shapes having a mescoscale cross-sectional dimension on the order of 0.1 .mu.m to 1000 .mu.m. In one embodiment, the devices are fitted with various flow-regulating features to facilitate unimpeded movement of the motile cells of interest along the flow channels. In another embodiment, devices are provided for conducting replicate motile cell assays, or for conducting a series of different assays using a single test sample. In another embodiment, preparative devices are provided for separating and collecting selected motile cell types of interest.

Abstract: A synthetic strategy for the creation of large scale chemical diversity. Solid-phase chemistry, photolabile protecting groups, and photolithography are used to achieve light-directed spatially-addressable parallel chemical synthesis. Binary masking techniques are utilized in one embodiment. A reactor system, photoremovable protective groups, and improved data collection and handling techniques are also disclosed. A technique for screening linker molecules is also provided.

Abstract: The invention relates to an immunoassay cassette useful for carrying out multistage immunoassays in an automated manner. In operation, the cassette assumes different operational positions in which solutions are transferred sequentially across an absorbent pathway containing assay reagents.

Abstract: A diagnostic test, and a device for conducting the test, for assessing whether patient chest pain is cardiac in origin and for differentiating between unstable angina and myocardial infarction as a cause of patient chest pain is described. The diagnostic test comprises simultaneously detecting at least three selected cardiac markers with the use of at least three different monoclonal or polyclonal antibody pairs, each member of which is complementary to a different marker, which is released by heart muscle at varying stages after the onset of chest pain and is indicative of the cause of the chest pain.

Abstract: This invention provides methods for determining whether a target nucleic acid sequence is present in a sample and methods for determining the amount of a target nucleic acid sequence present in a sample using flow-through hybridisation technology. This invention also provides different embodiments of these methods. Finally, this invention also provides devices where these methods are carried out.

Abstract: An apparatus for flow injection analysis is disclosed which comprises: (a) an open flow cell containing an upper cell body, a lower cell body contiguously affixed to the upper cell body, and a cell chamber provided in the upper cell body, the cell chamber having a bottom and a top, wherein the top of the cell chamber is open to an atmosphere; (b) a carrier fluid inlet port provided in a lower portion of the upper cell body and in communication with the cell chamber; (c) a fluid delivery device for introducing a carrier fluid into the cell chamber through the carrier fluid inlet; (d) an over-flow outlet setup in an upper portion of the upper cell body to allow exit of the carrier fluid and thus maintaining a constant fluid volume in the cell chamber; (e) a detector disposed in the lower cell body in such a manner that its detecting surface is placed at the bottom of the cell chamber and and facing upward; and (f) a sample injecting assembly, separated from the inlet port and the fluid delivery device for injec

Abstract: A method and apparatus for determining qualitatively or quantitatively the presence of analyte bound to a separation media without doing a bound/free separation. In the method, the bound fraction is collected in an assay region of a body of liquid which includes the free analyte, and the assay is performed by comparing the radiant-energy response in the assay region to the radiant-energy response in a control region of the body of liquid which is free of bound analyte. The apparatus has a chamber which contains the body of liquid, one or more collection elements and a control element and position in the body of liquid parallel to an opaque wall which has a colliminating slit in registry with each element. Each slit enables sensing of the radiant-energy response from the body of liquid between the slit and its associated elements.

Abstract: The invention is an improved single-step test device for detecting the presence of a pre-selected analyte in a urine stream. The device has a hollow outer casing and an assay material disposed within the casing. The outer casing defines: a urine inlet port; a viewing window; and at least one drainage vent spaced about the urine inlet port. The assay material is a sorptive material defining: a urine sample application region adjacent to, and in fluid communication with the urine inlet port; a capture region adjacent to the viewing window; and a fluid flow path for transporting liquid sample between the urine sample application region and the analyte capture region. The drainage vent is located to permit excess urine entering the casing from the urine stream to exit the casing thereby to minimize hydraulic pressure induced flooding of the assay material disposed within the casing and to reduce the frequency of false test results.

Abstract: A frameless chemical analysis film includes a reagent layer formed on a support sheet. When the frameless chemical analysis film which has been held on a resilient suction pad under a suction force supplied to the suction pad is transferred to a predetermined member, the suction force supplied to the suction pad is gradually released taking at least a time which the suction pad, which has been deformed under the suction force, takes to be restored to the original shape.

Abstract: A mesoscale sample preparation device capable of providing microvolume test samples, separated into a cell-enriched fraction and a fraction of reduced cell content, for performing various analyses, such as binding assays, determinations involving polynucleotide amplification and the like. Analytical systems including such devices are also disclosed.

Abstract: Disclosed are devices and methods for performing an assay which determines the presence or quantity of an analyte in a fluid sample by detecting binding of the analyte to at least one immobilized analyte capture reagent and washing unbound material from the immobilized analyte capture reagent. The devices and methods an elongated solid phase flow matrix, including capillary channels capable of driving capillary fluid movement, and further including (i) a first region adapted for receipt of the fluid sample, (ii) a second region at which the analyte capture reagent is immobilized, (iii) a third region for application of a wash reagent capable of removing unbound substances from the second region; and (iv) an absorbent reservoir of high volume capacity. The second region is positioned intermediate to the first region and the third region and intermediate to the absorbent reservoir and the third region. The device also includes means to detect analyte bound at the second region.

Abstract: Device for capturing a target molecule for the purpose of detecting it and/or assaying it, including a solid support on which is immobilized a ligand, the ligand being provided in the form of a conjugate resulting from the covalent coupling of a polymer with a plurality of molecules of the ligand. The polymer is an N-vinylpyrrolidone copolymer, and the conjugate is immobilized on the solid support by adsorption.When the ligand is capable of forming a complex with the target, the device is specific for a given target. When the device comprises, in addition, a bifunctional reagent capable of forming a complex, on the one hand, with the ligand and, on the other hand, with the target, the support on which the ligand is immobilized constitutes a universal capturing system.

Abstract: This invention relates to a diagnostic tests and devices for conducting such tests at the point of care or in a diagnostic laboratory for accurate, simple, and rapid assessment of chest pain. In particular, the invention relates to differential diagnosis of the origin of chest pain, e.g., whether the pain is cardiac in origin, and for differentiating between unstable angina ("UA"), myocardial infarction ("MI"), congestive heart failure ("CHF"), and other ischemic events affecting the heart, at early onset of patient chest pain. The invention further relates to diagnosis of the stage of the MI in a patient suffering from MI, and to prognosis of such a patient.

Abstract: Methods for determining the concentration of an analyte in a sample in which an analyte gradient is established and brought into contact with one or more zones that contain binding members that interact with the analyte and thereby produce a detectable signal. Devices that may be used to practice the disclosed methods are also provided.

Abstract: A magnetic material attracting/releasing control method makes use of a pipette device sucking a liquid from or discharging a liquid into a container. A magnet body or bodies are provided in a liquid suction line of the pipette device, and any magnetic material contained in liquid sucked into the liquid suction line by magnetic force are deposited on the internal surface of the line. The magnetic material is released and discharged together with liquid from the liquid suction line to a state where the effect of the magnetic force generated by the magnet body is cut off.

Abstract: The invention provides a fragment of C1q which is characterized in that a plurality of such fragments selectively binds immune complexes or aggregated immunoglobulins in the presence of monomeric immunoglobulin. The invention also provides a synthetic peptide comprising the sequence: ##STR1## or variants thereof capable of binding immunoglobulin. Like the C1q fragment, a plurality of the peptides can selectively bind immune complexes or aggregated immunoglobulins in the presence of monomeric immunoglobulin. As a result of this property, the fragments and peptides are well-adapted for removing immune complexes and aggregated immunoglobulins from fluids containing monomeric immunoglobulin, and for detecting or quantitating immune complexes in such fluids. The invention also provides a binding material for removing immune complexes or aggregated immunoglobulins from a fluid.

Abstract: The invention relates to a method of measuring antigens or antibodies in biological fluids in appropriately designed reaction cells in an automated analytical apparatus. The method includes the steps of contacting, in the reaction cell, the biological fluid with antibodies specific for a desired analyte antigen, which antibodies are coated on magnetic particulate carrier, under conditions such that binding of the antibody to the desired analyte antigen occurs, and detecting the presence or absence of an immunocomplex formed between the antibody and the desired analyte antigen. The automated analytical apparatus includes a closed circuit transfer path having means for transferring cells around the entire transfer path, and a thermostating period for each analysis to be performed with the automated analytical apparatus. The transfer path includes a loading station, a reagent delivery station, a mixing and washing station, a separating station and a discharging station.

Abstract: A disposable diagnostic device and method of its use are provided. The device comprises a housing containing first and second flow paths orthogonal to each other. The first flow path commences at a sample addition port and continues through a transport channel which feeds sample to an incubation area by means of capillary flow. The incubation area comprises a signal producing system and is underneath an optically-clear window. The first flow path terminates in a top waste reservoir which receives sample and wash fluid. The second flow path begins on one side of the incubation area at an inlet port over a side reagent reservoir. Liquid flows along the second flow path from the side reagent reservoir across the incubation area into the side waste reservoir. The incubation area may comprise agitation means for homogenous dispersion of reagent into liquid.