Abstract: A method for capturing a target substance in a sample, comprising the steps of preparing particles capable of capturing the target substance in a dispersed state in a fluid, aggregating the particles, and allowing the particles to capture the target substance in the sample by bringing the sample into contact with the particles aggregated.

Abstract: A simple easy to manufacture analytical device capable of performing membrane based immunoassays on batch of samples within 3 to 10 minutes wherein the method permits focused application of samples, costly labeled immunoassay and signal amplification reagents, said device includes an antibody-immobilized micro porous membrane, breadth corner layer of which is directly attached to a semi-rigid liquid-impervious body with water insoluble adhesive; absorbent body is provided separately and is not attached to analytical device during manufacture, absorbent body is wetted and is placed proximal to the lower surface of the membrane thereby forming networks of capillary channels with the absorbent body; flow of samples or reagents is always kept downwards and focused without application of any force to the absorbent body and the use of disposable adsorbent body permits stepwise addition of signal amplification reagents for ultra sensitive detection of diagnostically important molecules by visual examination of the m

Abstract: Device (1) for assaying a particulate analyte, comprising (a) a receptacle (2) for receiving a suspension (5) of particulate analyte, and containing label (3) for the particulate analyte, and (b) a porous detection material (4) that is permeable to label (3) but is impermeable to particulate analyte, the detection material (4) being arranged within receptacle (2) such that introduction of suspension (5) of particulate analyte into receptacle (2) forms liquid communication between label (3) and detection material (4). After liquid sample (5) is introduced into the receptacle (2), capillary flow through the porous detection material (4) begins. Particulate analyte cannot flow through the detection material (4) and is captured at its surface. Addition of liquid sample (5) also releases the label (3) within the receptacle (2), which is then free to flow through the detection material (4). Label (3) encounters the captured analyte and gives a signal (7).

Abstract: Methods, articles, and kits for obtaining elevated concentrations of a substance from a sample that has become bound, for example by providing a positive test result in an immunoassay or other binding assay. The concentrated substance is optionally subjected to further processing or analysis, for example to confirm the identity of the substance, such as a pathogenic organism in a food sample.

Abstract: The invention concerns a method for the detection of an analyte in a sample using analyte-specific conjugates which have at least one heterologous group for an analyte-independent binding to a control zone. The present invention additionally provides new conjugates and reagent kits.

Abstract: An analytical test device incorporating a dry porous carrier to which a liquid sample, eg. urine, suspected of containing an analyte such as HCG or LH can be applied indirectly, the device also incorporating a labelled specific binding reagent which is freely mobile in the porous carrier when in the moist state, and an unlabelled specific binding reagent which is permanently immobilized in a detection zone on the carrier material, the labelled and unlabelled specific binding reagents being capable of participating in either a sandwich reaction or a competition reaction in the presence of the analyte, in which prior to the application to the device of a liquid sample suspected of containing the analyte, the labelled specific binding reagent is retained in the dry state in a macroporous body, eg.

Abstract: A process for isolating and/or identifying at least one active chemical substance from a mixture of active and inactive chemical substances, is characterized by the steps: a) adding a target to said mixture and forming a complex of target and at least one active chemical substance of the mixture, b) separating the complex from the inactive chemical substances of the mixture, and either c) liberating and isolating and/or identifying at least one active chemical substance from the separated complex or d) identifying at least one active chemical substance of the mixture by subtracting from a chromatogram of the mixture of active and inactive chemical substances a chromatogram of the mixture of inactive chemical substances which is obtained after separation of the complex, and possibly liberating and isolating the at least one active substance from the separated complex.

Abstract: A substantial amount of a marker reagent associated with a measurement is measured in a marker reagent measurement area, and the substantial amount of the marker reagent is reflected by a result obtained in a reaction result measurement area where a reaction with a measurement target in an inspection target solution is measured. Thereby, an influence of external environmental factors, factors in a property of the inspection target solution, an erroneous operation in a measurement operation or the like is eliminated, whereby a chromatography measuring method employing a biosensor with higher accuracy and higher reliability can be provided.

Abstract: Methods and devices for electrochemical detection of a specific binding pair member utilizing a microsphere with an incorporated electroactive marker, wherein a member of the specific binding pair to be detected is bound, directly or through one or more intermediates, to the microsphere. Multiple specific binding pair members may be detected by use of electrochemically distinguishable electroactive markers. Microspheres with incorporated electroactive markers may include one or more functional groups for binding members of specific binding pairs, and are preferably insoluble in aqueous solvents but soluble in selected organic solvents.

Abstract: An improved method for separating materials is provided, using colloidal, magnetizable aggregates, optionally silanized, and coated with a one or more layers of novel polysaccharide derivatives. Materials separated by the aggregates of the invention include inorganic and organic molecules, viruses, organelles, and cells. The invention also relates to a kit for separating such materials. The separated materials are useful in analytical and preparative or in diagnostic and therapeutic techniques.

Abstract: A simple easy to manufacture analytical device capable of performing membrane based immunoassays on batch of samples within 3 to 10 minutes wherein the method permits focused application of samples, costly labeled immunoassay and signal amplification reagents, said device includes an antibody-immobilized micro porous membrane, breadth corner layer of which is directly attached to a semi-rigid liquid-impervious body with water insoluble adhesive; absorbent body is provided separately and is not attached to analytical device during manufacture, absorbent body is wetted and is placed proximal to the lower surface of the membrane thereby forming networks of capillary channels with the absorbent body; flow of samples or reagents is always kept downwards and focused without application of any force to the absorbent body and the use of disposable adsorbent body permits stepwise addition of signal amplification reagents for ultra sensitive detection of diagnostically important molecules by visual examination of the m

Abstract: The invention provides methods and compositions for azide tagging of biomolecules. In one embodiment of the invention, proteins are tagged by metabolic incorporation of prenylated azido-analog substrates. Examples of such analogs are azido farnesyl diphosphate and azido farnesyl alcohol. The azido moiety in the resulting modified proteins provides an affinity tag, which can be chemoselectively captured by an azide-specific conjugation reaction, such as the Staudinger reaction, using a phosphine capture reagent. When the capture agent is biotinylated, the resulting conjugates can be detected and affinity-purified by streptavidin-linked- HRP and streptavidin-conjugated agarose beads, respectively. The invention allows detection and isolation of proteins with high yield, high specificity, and low contamination without harsh treatment of proteins.

Abstract: A method and device are described to concentrate target organisms from a mixture of organisms. Beads (1) made of material such as nylon, polystyrene or glass are coated with antibodies of specific microorganisms. The beads (1) are contained in an enclosure (2) surrounded by grid material (4). The pore size of the grid is smaller than the size of the beads, to assure that the beads stay within the grid material and larger than the size of the microorganisms to allow the interaction of the microorganisms with the beads. A rod (5) is attached to the upper part of the enclosure (2) allowing the agitation of the device inside he growth medium containing the target organisms.

Abstract: An assay device and method are provided which allow the determination of the presence or absence of at least one analyte in a test sample, while providing specific identification of the test subject. The assay device includes a reaction medium having at least one reaction zone and at least one control zone, which is capable of providing a pattern suitable for identifying the test subject. The pattern suitable for identifying the test subject is preferably a fingerprint. In a preferred embodiment of the invention, the reaction zone and the control zone include at least one member of a ligand/receptor pair.

Abstract: The invention provides an improved test cell for detecting the presence of an analyte in a liquid sample. The device has an elongate casing defining a liquid sample inlet, a reservoir volume, a test volume, and a window through the casing at the test volume. Disposed within the cell is a sample absorbent, a novel biphasic substrate and a reservoir, together capable of transporting an aqueous solution within the casing along a flow path extending from the sample inlet through the test volume and into the reservoir volume. The invention further comprises a method for detecting the presence of an analyte in a liquid sample using the device and a biphasic chromatographic material for carrying out the method.

Abstract: The invention concerns a method for the detection of an analyte in a sample using analyte-specific conjugates which have at least one heterologous group for an analyte-independent binding to a control zone. The present invention additionally provides new conjugates and reagent kits.

Abstract: A device for collecting oral liquids includes a lateral flow chromatography strip having a collection pad for insertion into the mouth. The collection pad is separated from the remainder of the chromatography strip by a liquid impermeable removable barrier which prevents liquid in the collection pad from entering the chromatography strip. Once adequate oral liquid has been collected (as indicated by a sample sufficiency indicator), the device is withdrawn from the mouth and the barrier is removed to allow oral liquids to flow through the strip. The liquids interact with binding partners in the strip to provide test results, such as an indication that an analyte of interest is present in the liquid. The strip may be contained in a housing with an access opening through which the removable barrier may be manipulated, and windows through which test results may be viewed. This device avoids reflux of reagents from the strip into the mouth of a test subject during use.

Abstract: The present invention is directed to an enterotoxin adsorbent comprising a compound having a log P (P denotes a partition coefficient in an octanol-water system) value of not less than 2.50 as immobilized on a water-insoluble carrier.

Abstract: An assay method and kit for detecting the presence of a predesignated, target IgG antibody in a sample selected from one or more patient bodily fluids. The method comprises the following steps: (a) contacting the sample of one or more patient bodily fluids with a membrane-bound recombinant protective antigen to bind to the target IgG antibody in the sample; (b) previously, simultaneously or subsequently to step (a), binding the protective antigen (PA) with a conjugated label producing a detectable signal; and (c) detecting the signal whereby the presence of the target IgG antibody is determined in the sample by the intensity of the signal. The method can further comprise the step of evaluating immunization status of the patient from whom the sample came by comparing the signal or lack thereof with immunizations previously received by the patient. In a preferred embodiment, the recombinant protective antigen (PA) specifically binds to anthrax protective antigen-specific IgG antibodies.

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: A system and method for removing contaminants from a surface. The system is designed to use very small particles having means thereon which are capable of selectively binding to a contaminant or contaminants of interest. The particles may contain a dye to render the particles visible in order for a user to observe the application and removal of the particles. The particles also have magnetic properties which may be provided by a high iron content. A carrier can be used to apply the particles to a surface whereupon the targeted contaminants bind to the particles. The particles may then be readily removed from the surface using magnets. When the particle is removed, the targeted contaminants are also removed. The invention is especially useful for the removal of contaminants from skin.

Abstract: A lateral flow immunoassay device includes a membrane strip for enabling capillary migration of a sample therealong with a labeled reagent disposed on the membrane. The label reagent is formulated for suspension in the sample migrating therepast. A captive reagent is immobilized on the strip on a path of sample migration and the captive reagent is formulated to bind to the labeled reagent to form a visible colored site on the strip. An element is provided for changing the strip to a color which enhances visual perception of the colored site.

Abstract: This invention provides methods of retentate chromatography for resolving analytes in a sample. The methods involve adsorbing the analytes to a substrate under a plurality of different selectivity conditions, and detecting the analytes retained on the substrate by desorption spectrometry. The methods are useful in biology and medicine, including clinical diagnostics and drug discovery.

Abstract: A colloidal system for detection of a variety of analytes involves techniques which permit reconstitution of a desiccated substance such as for surface enhanced Raman spectroscopic analysis and multiple sensors at once, each having different spectra through the use of markers or the like. Competitive assay techniques and a variety of substances are explained to permit a practical an versatile system which can also be used for immunological assays and can include antibodies tagged to provide spectroscopic indicia.

Abstract: An immunological test kit suitable for the rapid detection of ciguatoxin and related low molecular weight lipid polyether marine toxins in fish tissues in the field, home or laboratory. The test procedure utilizes a synthetic membrane laminated onto one end of a solid plastic stick, which is immersed into alcohol with a piece of fish tissue. The membrane is then removed and dried thoroughly, then placed in the suspension of mixed colored beads coated with anti-ciguatoxin. The membrane is then rinsed in water and the intensity of the color compared with a standard range of colors formed (0-3+). The color intensity is proportional to the concentration of toxin in the piece of tissue. The kit includes the synthetic membrane on a plastic stick, a suspension of mixed colored beads coated with anti-ciguatoxin antibody, testing instruments, and a supply of solvent.

Abstract: The invention provides an improved test cell for detecting the presence of an analyte in a liquid sample. The device has an elongate casing defining a liquid sample inlet, a reservoir volume, a test volume, and a window through the casing at the test volume. Disposed within the cell is a sample absorbent, a novel biphasic substrate and a reservoir, together capable of transporting an aqueous solution within the casing along a flow path extending from the sample inlet through the test volume and into the reservoir volume. The invention further comprises a method for detecting the presence of an analyte in a liquid sample using the device and a biphasic chromatographic material for carrying out the method.

Abstract: A catcher, having an immunological epitope, is fixed to a detection zone of a spreading layer. A marker, capable of easy detection, has an inmmunological epitope. The marker and bispecific antibodies are soluble so that they can move on the spreading layer. The bispecific antibodies include a first bispecific antibody, having specificity for the detectable material in the fluid sample and the marker, and a second bispecific antibody, having specificity for the detectable material in the fluid sample and the catcher. Pore sizes and particle diameters are set so that the reaction product in which the marking elements and the particles are bonded are caught at a catching section. The concentration of the marking elements and the particles are increased to improve detection sensitivity. The result is an inexpensive and simple detection apparatus being highly-sensitive for the immunological detection of a detectable material, without wasting valuable antibodies.

Abstract: Displacement assays, under non-equilibrium conditions, are performed by flowing a liquid sample through a membrane having binding elements with binding sites saturated with a labelled form of the analyte. Analyte in the sample displaces, under non-equilibrium conditions, the labelled form of the analyte from the membrane. The displaced labelled form of the analyte may then be detected.

Abstract: Staphylococcus aureus virulence genes are identified, thereby allowing the identification of novel anti-bacterial agents that target these virulence genes and their products, and provision of novel S. aureus mutants useful in vaccines.

Abstract: The invention provides extraction columns for the purification of an analyte (e.g., a biological macromolecule, such as a peptide, protein or nucleic acid) from a sample solution, as well as methods for making and using such columns. The invention is characterized by the use of low dead volume columns, which is achieved in part by the use of low pore volume frits (e.g., membrane screens) to contain a bed of extraction media in the column. Low dead volume facilitates the elution of the captured analyte into a very small volume of desorption solution, allowing for the preparation of low volume samples containing relatively high concentrations of analyte.

Abstract: The invention is generally directed toward an analytical method to determine the concentration of the free analyte fraction in a sample. More particularly, the method encompasses applying a sample comprising a free and bound analyte fraction to an affinity column capable of selectively extracting the free fraction in the millisecond time domain. The signal generated by the free fraction is then quantified by standard analytical detection techniques. The concentration of the free fraction may then be determined by comparison of its signal with that of a calibration curve depicting the signal of known concentration of the same analyte.

Abstract: The invention concerns the stabilization and amplification of electrochemiluminescence signals in detection methods.

Abstract: The analytical process utilized in the system of this invention comprises three (3) step distinct steps wherein an analyte of interest in a test sample is initially labeled and subsequently isolated within a porous medium of a test device. Once isolated within the medium, the label is displaced from the analyte, or from the complex with the analyte, and converted, under electrolytic condition, to a metallic species which is caused test to deposit upon a working electrode of the test device. This working electrode is part of an electrode array that is positioned coincident with the porous medium, yet maintained physically remote therefrom. This deposit is then stripped from the working electrode, under anodic stripping conditions, and the current generated within the electrode array monitored. The characteristic response curve that is produced thereby can be correlated with the identity and concentration of the analyte(s) with the test sample.

Abstract: Methods and devices for the detection and/or quantification of an analyte in a sample are provided. These are positive detection methods and devices, in that the more analyte is present in the sample, the stronger the signal that is provided. Devices of the invention include a mobilization zone including a mobile or mobilizable detectable analyte analog, a sample application area, primary and secondary capture areas each including an immobilized binding partner having a binding affinity for the analyte being tested for a detectable analyte analog. The mobilization zone, sample application area, primary and secondary capture area are in fluid continuous contact with each other. In these devices, the first immobilized binding partner has an equal or lower apparent affinity for the analyte than it has for the detectable analyte analog.

Abstract: Approaches are described for separating plasma from whole blood samples and include the use of magnetically attractable particles associated with an agglutinating agent. The magnetically attractable particles bind the cellular components in a whole blood sample. Application of a magnetic field gradient to a container with the blood sample and the magnetically attractable particles draws the particles to the surface of the container near the source of the magnetic field gradient. The plasma can be removed and stored or used for monitoring or detecting analytes in the plasma.

Abstract: In this disclosure, novel caanabinol-based tracers suitable for use in immunoassays that detect cannabinoids in a biological sample are disclosed. These cannabinol-based tracers are particularly useful in a continuous flow displacement immunoassay. The disclosure also describes the processes for synthesizing the novel tracers, and the application of these tracers in fluorescence immunoassays for detecting and quantifying cannabinoids in biological samples.

Abstract: A method and device is disclosed for rapidly identifying a large number of proteins by placing a protein mixture in a sample chamber of an electrophoresis gel, and performing electrophoresis to separate the mixture by molecular weight, in a direction of separation, into a two-dimensional separation pattern in the gel. The separation pattern is transferred to a membrane, such as a sheet of nitrocellulose, and a plate with a set of separate, side-by-side slots is then applied to the membrane. A different antibody mixture is introduced into each of the slots by perfusing each antibody mixture under pressure through the slots. The antibody mixture that is perfused through each slot recognizes several different proteins of sufficiently different molecular weights that different protein bands can be resolved by the antibody mixture in each slot.

Abstract: A chromatography assay device and method for use with whole blood samples utilizing a red blood cell separating agent to aggregate red blood cells and permit plasma or serum to flow by capillary action and a neutralizing agent to neutralize any effects the red blood cell separating agent may have on the device and method.

Abstract: Disclosed is a device and method of use for detecting polyvalent analytes such as antibody to the AIDS virus, utilizing an inverse sandwich method. The test device comprises a first substance having an epitope, bound to a label and capable of moving within the test device. The test device further comprises a second substance immobilized to the test device and spatially separated from the first substance. The second substance has an epitope substantially similar to the epitope of the first substance. Upon application to the test device, the polyvalent analyte binds to the first substance and moves within the test device to the location of the second substance with both polyvalent analyte and first substance are immobilized at location of the second substance. Polyvalent analyte is detected by the presence of the label at the location of the second substance. Also disclosed is a control substance for use with the device that can be used to determine completion of the test and viability of the device.

Abstract: A method and apparatus for extracting, identifying, and manipulating proteins or peptides from a solution uses paramagnetic beads having a coating with an affinity for the target component. In one embodiment, paramagnetic beads coated with C18 are used to adsorb proteins and peptides. The beads can be used to purify, immobilize and assay antibodies. By cycling the beads, many times greater molar amount of binding partner may be separated from a solution. A magnetic probe is used to capture the beads and transfer the beads to selected processing stages.

Abstract: This invention provides novel methods for monitoring urine for type II collagen fragment using a combination of a capture antibody and a detection antibody, such that type II collagen is distinguished from other collagen fragments.

Abstract: A method to facilitate recovery troponin I and/or troponin T from a sample comprising addition of troponin C to the sample or to a surface from which the troponin I and/or troponin T are recovered.

Abstract: An immunochromatographic assay employing superparamagnetic particles to lable the target analytes. An opaque cover prevents misinterpretive readings in field situations and provides a protective surface on the porous membrane. Additional features include separability of the test strip from any backing or housing which is configured to support the strip, and that quantitative measurements of the target analytes are easily and accurately made by means of an electromagnetic reader device.

Abstract: A disposable, dry chemistry analytical system is disclosed which is broadly useful for the detection of a variety of analytes present in biological fluids such as whole blood, serum, plasma, urine and cerebral spinal fluid. The invention discloses the use of the reaction interface that forms between two liquids converging from opposite directions within a bibulous material. The discovery comprises a significant improvement over prior art disposable, analytical reagent systems in that the detectable reactant zone is distinct and separate from the unreacted reagents allowing for the use of reaction indicators exhibiting only minor changes as well as extremely high concentrations of reactants. In addition, staged, multiple reagents can be incorporated. Whole blood can be used as a sample without the need for separate cell separating materials.

Abstract: A testing apparatus 10 having an absorbent matrix 12, including a membrane 14 which contains a plurality of counter-ions 16. Chromionophore (or fluorionophore)s 18 and affinophores 22 compete to carry ions into the membrane 14 and neutralize the charge of the counter-ions 16. Biological recognition molecules 42 bind to a portion of the affinophores 22 and prevent them from entering the membrane 14, thereby allowing more chromionophore (or fluorionophore)s 18 to enter the membrane 14. The portion of affinophores 22 bound to the biological recognition molecules 42 is inversely proportional to the amount or concentration of analyte 40 occurring within the solution or medium 30. The result of this is that the color of the membrane-covered matrix changes in a manner related to the concentration of the analyte. One application of this apparatus is a strip test for prediction of ovulation.

Abstract: A method of assaying for an analyte including the steps of: (i) passing a sample suspected of containing an analyte and reagents comprising a target ligand-analyte receptor conjugate and a detectable tracer containing a label for the analyte through filter apparatus containing a plurality of discrete flow zones wherein at least one zone functions as a capture zone having bonded thereto a receptor ligand for said target ligand; (ii) allowing the sample and accompanying reagents to incubate prior to passage through said at least one zone to facilitate formation of complex(es) of said conjugate and said at least one analyte in a liquid or fluid phase; and (iii) detecting the presence of analyte in the sample by activation of the label in said at least one zone after binding of the complex(es) conjugate to the associated receptor ligand(s).

Abstract: The present invention relates to a simple immunochemical semi-quantitative assay method according to chromatography, which comprises trapping a certain amount of an analyte in a sample with a predetermined amount of a fixed antibody for the analyte before qualitative analysis of the analyte, the certain amount corresponding to the amount of the fixed antibody, and thereby decreasing a concentration of the analyte to be subjected to subsequent immunochemical qualitative determination, and an apparatus therefor.

Abstract: A solid diagnostic device for the quantitative determination of substances of biological affinity in biological fluids is described. A process is also described in which the biological fluid is brought into contact with a specific functional sector of the device, the fluid migrates through several functional sectors situated beside one another and containing suitable reagent components, and one or more substances of biological affinity are detected in such functional sectors which contain, for each substance to be detected, at least one combination partner of biological affinity, attached to a solid phase.

Abstract: A biological fluid collection container comprising a cup member, a lid assembly removably mounted to the cup member comprising a housing with a downwardly extending cylindrical skirt, a luer lock with a throughgoing bore extending from one side of the lid housing. A hollow tube extends from the other side of the lid housing adjacent the luer lock and is axially aligned with the throughgoing bore of the luer lock. The hollow tube is provided with a plurality of throughgoing holes leading into its lumen along its surface to provide for a sampling along various liquid level layers of the biological fluid specimen collected in the cup member so that when the biological fluid specimen is removed from the cup member a representative sampling is obtained.

Abstract: A chromatographic test strip comprising a solid support having at least a first portion and a second portion with said portions being in the same plane so as to permit capillary flow communication with each other. The sample is added to the first portion. The first portion also may comprise a tracer portion having a tracer movably supported therein. The tracer consists of a visible particulate marker. In the second portion, a binder is immobilized. The test strip is useful in a variety of immunoassays.