Abstract: The assay reagent and kit of the present invention suppress non-specific binding of a labeled substance onto a solid phase, and can assay one or more species of antibodies or one or more species of antigens by means of a single reagent in a simple manner. The assay method involves reacting immunological ligands in a test sample with the assay reagent which contains a combination of components (A) and (B), thereby forming complexes, which complexes are captured onto the independently and separately present Solid phases (C), to assay the label contained in the complexes.

Abstract: The invention relates to the area of protein determinations in homogeneous solution by means of antigen-mediated precipitation by antibodies or using latex materials coated with antibodies and subsequent optical measurement of the precipitation reaction by a nephelometric or turbidimetric measurement.

Abstract: A method for the separation of at least one specific binding entity from a mixture of binding entities by the steps of contacting a mixture of binding entities with immobilized peptides in which the peptides specifically bind to the specific binding entities and the peptides contain an amino acid which facilitates removal of the binding entities from the peptides, and separating the immobilized peptide/specific binding entity complexes from the mixture of binding entities. A change in incubation conditions facilitates removal of the binding entities from the immobilized peptides.

Abstract: A method is provided for preparing lipoprotein (a) from a volume of biological fluid that is substantially free of lipoproteins of another class. The method involves an ultracentrifugation step in which at least one fraction is recovered that contains Lp(a). This material is then reacted with immobilized ligand to remove non-Lp(a) interfering substances from the fraction, the Lp(a) remaining unbound. The non-reacted Lp(a) is subsequently obtained in a form that is suitable for use in the analysis of any of protein concentration, protein isoform determination or cholesterol assays. A method of identifying and measuring an amount of one or more isoforms of Lp(a) is further provided.

Abstract: Two or more analytes having the same action, or having different actions in spite of their similar structures, or two or more analytes having the same action and the same detectable chemical characteristics, in samples derived from living bodies, etc., can be measured rapidly and easily by forming one or more complexes with one or more affinity substances, separating the complexes by using high pressure liquid chromatography, followed by measurement of the amount of an affinity substance or one of the analytes.

Abstract: A method for quantitatively determining cholesterol in high density lipoproteins, in which, prior to the determination of cholesterol by an enzymatic method, a surfactant and a substance which forms a complex with lipoproteins other than high density lipoproteins are added to a sample containing lipoproteins.The method does not require any pretreatments such as centrifugal separation. With a simple operation, cholesterol in HDLs can be measured effectively. Also, this method can be adopted in a variety of automated analyzers, and thus is very useful in the field of clinical assays.

Abstract: A method and apparatus for separating solid supports formed of magnetic particles on which immunocomplexes are bound, from a liquid phase includes a reaction container containing a fluid in which magnetic particles having immunocomplex bound thereon are suspended. The reaction container is positioned at a flock forming station, where the fluid is subjected to an alternate current magnetic field having a temporally varying intensity by an electromagnetic. The magnetic particles are flocculated with each other due to the application of such varying magnetic field to form a multiplicity of flocks. A stronger magnetic field then is applied to the resulting contents in the reaction container by a permanent magnet. The flocks are magnetically fixed on the inner wall surface of the reaction container by the action of the stronger magnetic field.

Abstract: The hydrogel-forming polymers are used as absorbents for collecting and concentrating solutions. A solution to be concentrated can be contained in a dialysis membrane, with the hydrogel-forming polymer, or mixture thereof, on the outer surface of the membrane. A hydrogel-forming polymer can be added directly to the solution to be concentrated and the resulting concentrate separated from the gel by filtration of decanting. A hydrogel-forming polymer can be placed in a container formed of porous material and the container can be added to the solution to be concentrated and physically removed after concentration has occurred. Hydrogel-forming polymer can be used as a liquid collection in diagnostic membrane assay cartridges.

Abstract: Methods are disclosed for separating a component of interest from a mixture containing the component of interest and other components. The method comprises contacting a first liquid medium containing the component of interest and other components with a second liquid medium that is of different density than and/or of different viscosity than the first liquid medium. The contact is carried out in such a way that mixing of the media is minimized or avoided. The component of interest is bound to magnetic particles. The contacted first liquid medium and second liquid medium are subjected to a magnetic field gradient to allow the magnetic particles to migrate into the second liquid medium and separation of the component of interest from other components is realized. Also disclosed are assays employing the present method. Kits for carrying out the present method and assays are also disclosed.

Abstract: A patient's health may be diagnosed by centrifuging blood samples in a transparent tube, which tube contains one or more bodies or groups of bodies such as floats, inserts, liposomes, or plastic beads of different densities. Each density-defined body carries analyte-capture binding materials such as antigens or antibodies, which are specific to an epitope, or other specific high affinity binding site on a target analyte which target analyte may be in the blood or other sample being tested; and the level of which analyte is indicative of the patient's health. At least one labeled binding material which is also specific to an epitope, or other specific high affinity binding site on the target analyte is added to the sample so as to form labeled binding material/analyte/body complexes in the sample.

Abstract: The present invention relates to a binary assay method capable of providing wide dynamic range, a high degree of precision and rapid processing times in which analyte is reacted successively with two independently determinable forms of solid-supported binding partner and also with a labelled ligand having affinity for the analyte or binding partner. The analyte concentration is determined from signals deriving from the resulting two forms of analyte-binding partner-labelled ligand systems by reference to a double standard calibration curve. A kit for use in the method is also disclosed.

Abstract: The invention is a device and a method for collecting samples mixing the samples with test reagents, and acting as a container in which the mixture can be incubated and the test reaction viewed by microscope or imaging device. This device enables an entire test to be performed in one simple step without complicated handling procedures. The device consists of a cartridge with a well with micro-lances imbedded in the bottom of the well and an overlying micro-baggy containing a mixture of reagents. There are two reagents present in the micro-baggy: the first consisting of antibodies coupled to paramagnetic microspheres and the second consisting of antibodies coupled with a fluorochrome. A test subject presses down onto the micro-baggy and at the same time punctures his/her finger or thumb on the micro-lances. Once the finger has been lanced, breaking the micro-baggy, the reagents mix with the test subject's blood. The well is then covered by a clear mylar strip.

Abstract: Trace components in samples can be measured rapidly with high precision by applying interaction between an analyte to be measured and an affinity substance and using a membrane having specific separating capability.

Abstract: The present invention is a method and apparatus useful for the detection of bloodgroup antigens and antibodies. There are two preferred embodiments of the method: a direct assay and an indirect assay. The direct assay comprises adding a sample of erythrocytes to a reaction tube charged with a column of immunoreactive particles having an immunoglobulin binding ligand selected from the group consisting of Protein A, Protein G, Protein A/G or a universal kappa light chain binding protein coupled to the surface of the particles. Antibodies specific for bloodgroup antigens tested for are coupled to the ligand on the particles. The reaction tube is then centrifuged for a time sufficient to force to the bottom of the reaction tube erythrocytes that do not attach to the antibodies on the particles.

Abstract: Disclosed is an apparatus designed to be used for enriching specific cell types from cell mixtures. The apparatus includes a centrifugable device that includes a constriction defining a lower region and a defined cell separation medium. The constriction prevents mixing between the upper and lower portions of the device. Also disclosed are methods that use precisely defined cell separation media to isolate specific cells from cell mixtures, including CD34.sup.+ hematopoietic progenitor cells from blood or bone marrow, nucleated fetal cells from maternal blood, specific tumor cells, dendritic cells, natural killer cells, and natural suppressor cells from various body fluids, and for enrichment or depletion of T cell lymphocytes. Also disclosed is a density adjusted cell separation technique used to augment the above apparatus and enrichment methods. The apparatus and enrichment methods are useful in various diagnostic and therapeutic regimens.

Abstract: A method for determining the presence and/or concentration of a target substance e.g. protein, nucleic acid, bioparticle etc. in a fluid sample is provided. The method disclosed combines elements of immunoassays, coated cup assays and magnetic particle separation to effect the quantitation and recovery of an analyte in solution. Also the method ensures the non-reorientation of magnetically collected material by linking the magnetic particles to a collection surface via a specific binding pair. This linkage immobilizes the magnetic-analyte-containing material and thus allows for vigorous washing and reagent addition without significant redistribution or displacement. Thus the assay of this invention offers the speed of diffusion controlled kinetics as in a ferrofluid assay, the speed of collection of labeled target substance as in a magnetic assay as well as the ability to magnetically monolayer the ferrofluid, all of which is combined with the ease of washing and signal detection found in a coated cup assay.

Abstract: The present invention relates to methods of enriching breast tumor cells from a patient's body fluids. In particular, it relates to the use of a cell-trap centrifugation tube containing a specific density gradient solution adjusted to a specific density to enrich for breast tumor cells from a cell mixture. The tube allows the desired cell population to be collected by decantation after centrifugation to minimize cell loss and maximize efficiency. In addition, the method can be further simplified by density-adjusted cell sorting which uses cell type-specific binding agents such as antibodies and lectins linked to carrier particles to impart a different density to the non-tumor or tumor cell populations allowing the breast tumor cells to be separated from the non-tumor cells in a more convenient manner.

Abstract: The present invention relates to methods of enriching fetal cells from maternal body fluids. In particular, it relates to the use of a cell-trap centrifugation tube containing a gradient solution adjusted to a specific density to enrich for fetal nucleated red blood cells from maternal blood. The tube allows the desired cell population to be collected by decantation after centrifugation to minimize cell loss and maximize efficiency. In addition, the method can be further simplified by density-adjusted cell sorting which uses cell type-specific binding agents such as antibodies and lectins linked to carrier particles to impart a different density to undesired cell populations allowing the fetal cells to be separated during centrifugation in a more convenient manner. The rapid fetal cell enrichment method described herein has a wide range of applications, including but not limited to, gender determination and prenatal diagnosis of genetic diseases without the use of invasive procedures.

Abstract: A method for separation of a mixture of biological entities into at least three distinct, subpopulations. Different antibodies are provided, with each antibody bound to a solid support in a unique manner such that by a manipulation of the physical or chemical environment, the bonds between the antibodies and the solid supports can be selectively broken. The mixed population of cells is incubated with the antibodies. The cells are magnetically separated from a test medium and collected in a monolayer upon a collection surface. Then by manipulation of the physicochemical environment, specific linkages can be broken and desired cell subpopulations released from the collection surface. This method has medically significant diagnostic and therapeutic applications, as entire cell types can be separated from non-malignant medically vital cell types. Cancer can be diagnosed, staged, and monitored. Genetic analysis from maternal blood, CVS, or amniocentesis samples is possible.

Abstract: The invention relates to a method of using a pair of leucine zipper peptides for in vitro diagnosis, in particular, for the immunochemical detection and determination of an analyte in a biological liquid. In one method, the first leucine zipper peptide is immobilized by attaching it to a solid support, the second leucine zipper peptide is coupled to a specific binding partner for the analyte, the two peptides are brought into contact, the sample of the biological liquid is brought into contact with the immobilized first peptide and the specific binding partner for the analyte, and the amount of analyte bound to the binding partner is determined. The leucine zipper peptides are preferably v-fos and c-jun.

Abstract: Disclosed are materials and methods for detecting biomolecules in samples employing transponders having memory elements associated with particle(s) used as a solid phase in art assay, and information pertinent to the assay is encoded on the transponder memory elements. A dedicated read/write device is used remotely to encode or remotely to read the information encoded on the transponder memory elements. The invention can be used in direct or competitive ELISA-type assays, or in multiplex assays for the simultaneous assay of several analytes.

Abstract: A patient's health may be diagnosed by centrifuging blood samples in a transparent tube, which tube contains one or more bodies or groups of bodies such as floats, inserts, liposomes, or plastic beads of different densities. Each density-defined body carries analyte-capture binding materials such as antigens or antibodies, which are specific to an epitope, or other specific high affinity binding site on a target analyte which target analyte may be in the blood or other sample being tested; and the level of which analyte is indicative of the patient's health. At least one labeled binding material which is also specific to an epitope, or other specific high affinity binding site on the target analyte is added to the sample so as to form labeled binding material/analyte/body complexes in the sample.

Abstract: Disclosed are devices and methods for analyzing a fluid cell containing sample. The devices are composed of a solid substrate, microfabricated to define at least one sample inlet port and a mesoscale flow system. The mesoscale flow system includes a sample flow channel, extending from the inlet port, and a cell handling region for treating cells disposed in fluid communication with the flow channel. The devices may further include a component for inducing flow of cells in the sample through the flow system. In one embodiment, the cell-handling region may include a cell lysis component to enable the lysis of cells in the sample, prior to, e.g., the detection of an intracellular component in the cell sample. In another embodiment, the cell handling region may have a cell capture region, with binding sites which reversibly bind to a specific population of cells in the cell sample, to permit the isolation of the specific cell population from the sample.

Abstract: A novel approach to study changes in protein tyrosine phosphorylation during apoptosis, and thereby identify cells committed to apoptosis is presented, methods used to study apoptosis and tyrosine phosphorylation at the single cell level are combined to study directly whether apoptosis in hematopoietic cells is associated with changes in cellular phosphotyrosine levels. The changes in cellular phosphotyrosine content strongly correlated with the appearance of features of cell death such as cell shrinkage, DNA fragmentation and loss of membrane integrity.

Abstract: Methods and devices are disclosed which are useful for collecting magnetic materials in either internally or externally generated magnetic gradient fields, followed by resuspension into solution with a simple manipulation of the magnetic device. The methods provide for removal of excess reagent, washing of magnetic material, and resuspension for analysis, among other uses. The methods are applicable to all types of biological material that are susceptible to magnetic labelling, including, for example, cells, viruses, proteins, hormones, and receptor-ligand complexes. Several devices are disclosed to take advantage of the method for cellular and immunoassay applications, including both internal and external devices. Both flow-through and static separators are disclosed.

Abstract: A method of determining a hapten which comprises: (1) contacting the sample which contains or may contain the hapten with a first binding partner which binds the hapten; (2) separating the hapten bound to the first binding partner from material which is not bound by the first binding partner; (3) contacting the hapten bound to the first binding partner with a second binding partner which binds the hapten; and (4) assaying the hapten bound to a binding partner as is described. Kits are also described.

Abstract: An apparatus and method provide automated collection and transfer of particles from a liquid suspension to a glass slide for visual examination. A magnet is positioned adjacent to a solution which contains particles tagged with magnetic beads, for example cells, so that the magnetic particles flow toward the magnet and collect against a collection surface positioned between the particles and the magnet. A transfer mechanism applies a selected pressure to a second side of the collection surface for transferring collected cells to a viewing slide. The apparatus includes a device for dispersing the liquid suspension of particles prior to the collection process and for collecting particles against the collection surface with a spatial distribution advantageous for visual examination. The transfer operation maintains this spatial distribution.

Abstract: A method of binding aggregated immunoglobulin or immune complexes comprising contacting them with modified forms of C-reactive protein. The method may be employed for diagnostic and therapeutic purposes and to deplete fluids of aggregated immunoglobulin or immune complexes. Further, a method of reducing the levels of immune complexes in a mammal comprising administering modified-CRP to the mammal, and a method of binding immunoglobulins comprising contacting them with modified C-reactive protein. Also, a method of binding aggregated immunoglobulin or immune complexes comprising contacting them with antibody to neo-CRP, and a method of modifying C-reactive protein. Finally, a test kit for detecting or quantitating immune complexes and a device for removing aggregated immunoglobulin or immune complexes from fluids are disclosed.

Abstract: A separation procedure for separating a selected desired or undesired population from a biological sample utilizing relatively heavy, dense particles and gravity sedimentation. The particles have one or more reactants bound thereto which are specific to and will bind with the selected population. The particles preferably are mixed with the sample by repeatedly causing the particles to settle through a substantial portion of the sample to bind to the selected population. The particles with the bound selected population then are allowed to preferentially settle in the sample and the supernatant including the non-selected population is separated from the particles with the selected population bound thereto. The particles can be heated for sterilization and endotoxin removal.

Abstract: Inter alia, a process for the selective removal of salivary .alpha.-amylase from a sample comprising salivary .alpha.-amylase and pancreatic .alpha.-amylase characterized in that there is used a monoclonal antibody against salivary .alpha.-amylase, which is immobilized or is coupled to a physically separable or seperate support and which exhibits a binding affinity towards salivary .alpha.-amylase of at elast 1.times.10.sup.7 l/m and a cross-reactivity with pancreatic .alpha.-amylase of less than 1% is disclosed. The remaining pancreatic .alpha.-amylase may be assayed.

Abstract: This invention is intended to provide a process by which a complex formed by the interaction between one or more analytes to be measured and affinity substance can be more effectively separated from substances existing together therewith which tend to affect the detection of the complex, for example, free affinity substance, by using high pressure liquid chromatography (HPLC); and a process for measuring a trace component by utilizing said separating process.This invention is characterized in that a substance which has been modified with a substance capable of changing properties of the complex (a separation-improving substance) and has affinity for the complex is attached to the complex. Because of this characteristic, the invention is effective in that the position of elution of said complex in the HPLC can be freely controlled.

Abstract: Disclosed is a method of isolating a ligand from a sample, the method including: providing a hybrid molecule including the receptor for the ligand covalently bonded to the first member of a specific binding pair; contacting sample with the hybrid molecule to form an affinity complex between the ligand and the hybrid molecule; and isolating the affinity complex using the second member of the specific binding pair. Also disclosed is a c-kit ligand, nucleic acid encoding such a ligand, and recombinant cells containing such nucleic acid. The c-kit ligand may be used to stimulate hematopoietic cell growth.

Abstract: The amount of an analyte in a sample derived from a living sample is measured by reacting the analyte with an excess of a substance having affinity for the analyte, followed by separation of complex by high pressure liquid chromatography and measurement using a linear calibration curve representing the peak area values associated with known concentrations of analyte.

Abstract: Methods and devices are provided for separation of magnetic particles and/or magnetic-associated substances from non-magnetic associated substances and media. The methods are specifically applicable to biological separation, and utilize a phase phenomenon arising from mutual interactions between suspended magnetic particles and interactions with the suspension medium. The phenomenon is exploited to produce and maintain a distinct, structured phase of magnetic particles, or ferrophase, within a multi-phase liquid system. A ferrophase is established within a separation chamber prior to introducing therein a test sample containing the target substances to be separated. The formation of a ferrophase is used to transport target substances from regions of relatively low magnetic field gradient to regions of relatively high magnetic field gradient within a high-gradient magnetic separation apparatus.

Abstract: An improved one-step immunochromatographic assay which involves the binding of a predetermined amount of analyte to an antibody, enabling the control of the assay sensitivity, is disclosed. The system is especially useful as a controlled sensitivity fecal occult blood assay. Antibodies to a desired analyte, present at a predetermined concentration, are deposited on the sample pad of the reaction unit. The antibody binds analyte present in the sample, up to a threshold amount. Analyte which is present in the sample at a level above the threshold amount proceeds unbound through the sample pad and onto a membrane, where it reacts with an antibody-coated latex and a second, immobilized antibody to generate a positive signal.

Abstract: A method is disclosed for detecting abnormal epitope expression of protein molecules by immunocapturing a constant number of protein molecules from a test and a reference sample using a limited amount of capturing antibodies, saturating them with its corresponding protein from the test and reference samples to provide a constant, known amount of the immobilized protein for comparison, labelling an epitope on the immobilized protein by means of a labelled probing antibody specifically reactive with the epitope and correlating any difference in labelling between the test and the reference sample to the absence or modification of the epitope in the protein of the test sample.

Abstract: A suspension of inert particles is prepared in an aqueous solution, to which an antibody or an antigen and a carrier-bound antigen or antibody, respectively, are added in any desired order. After centrifuging, the positive, weakly positive, or negative reaction can easily be recognized on the basis of a simple pattern.

Abstract: A method of assessin glycated blood protein in a sample which comprises separating glycated and non-glycated protein using a liquid phase precipitation reagent, contacting the sample before or during the separation with a signal forming agent capable of binding preferentially to the glycated protein, and assessing the signal forming agents.

Abstract: Desired cells are positively separated from a mixture of cells using multiple stages of affinity surfaces. Bound cells from each surface are removed and subjected to a further surface for further enrichment.

Abstract: An immunoassay method for the detection or quantitation of an analyte suspected of being in a solution comprising: (a) combining said specimen, a first binding component, insoluble particles, and second binding component labelled with a signal generating material in a solid phase retention and separation apparatus having a sufficient pore size such that said particles are trapped within said filter yet permitting rapid passage of fluid therethrough in such a manner that an immunological reaction occurs if analyte is present in said specimen, resulting in the formation of an immunocomplex of insolublized first binding component:analyte:second labelled binding component on or within said filter means; (b) separating bound from unbound material; and (c) determining the presence and/or amount of signal produced which is correlative with the amount of analyte present in the solution.

Abstract: A device for collecting a specimen, including (a) a test vessel for containing a solution containing an immunocomplex, which is a complex as a result of an antigen-antibody reaction between a specimen and a magnetic-labeled antibody containing a magnetic micro-particle and an antibody fixed to the micro-particle, (b) an external magnetic field generating device for generating a magnetic field, preferably a gradient magnetic field and applying it to the solution in the test vessel to effect local concentration of the immunocomplex to a predetermined position, (c) a magnetic member for collecting the immunocomplex at the position of local concentration, and (d) a moving mechanism for achieving relative movement between the magnetic member and the test vessel.

Abstract: A biological sample such as feces, sputum, cervical tissue, pleural fluids, exudates, cytologic specimens, or the like, is tested for the presence or absence of: ova; parasites; microorganisms; inflammatory, neoplastic tissue cells; or other target materials which are indicative of infestation, disease or infection. The sample is mixed with a buffer fluid and placed in a transparent tube which contains a volume-constricting cylindrical insert for gravimetric separation of components of the sample. The mixture is centrifuged, and the annular space between the insert and tube bore is examined under magnification for the presence of the target materials.

Abstract: A vessel for conducting blood cell agglutination assays is disclosed. A barrier retains reactants in an upper chamber during incubation, then, in response to a force, permits reagents to enter a lower chamber containing a matrix for separating agglutination.

Abstract: A novel polypeptide, designated plasma carboxypeptidase B (PCPB), has been purified from human plasma. It has been cloned from a human liver cDNA library using PCR amplification. Provided herein is nucleic acid encoding PCPB useful in diagnostics and in the recombinant preparation of PCPB. PCPB is used in the preparation and purification of antibodies thereto, in the purification of plasminogen, in the inhibition of plasminogen activation by t-PA in the presence of fibrinogen, and in diagnostic assays.

Abstract: A magnetic separator for isolating magnetically-labeled substances of interest, such as immunological agents, from a non-magnetic test medium using a method of high gradient magnetic separation. The target substance is contacted with microscopic magnetic particles having a receptor for binding with the target substance. The test medium containing the magnetic particles is held in a non-magnetic container and placed into a gap within an arrangement of magnets for causing the magnetic particles to adhere to selected locations upon the interior wall of the container. The quantity of magnetic particles may be controlled to cause the magnetic particles collected upon the interior wall to form a monolayer. The magnets are arranged upon a yoke which may provide linear, surrounding multipolar, or partially surrounding multipolar configurations of magnetic pole faces about the gap.

Abstract: A hydrophobic polymer such as polysulfone or polyethersulfone is modified to contain an increased number of functionalizable chain ends such as by treating with an alkali hydroxide to provide hydroxyl groups. A linker is covalently bonded to a chain end of the polymer and a macromolecule is covalently bonded to the linker. A ligand may be covalently bonded to the macromolecule. The macromolecule can be a natural polymer, a synthetic polymer or a biologically active species. The hydrophobic polymer is preferably in the form of a microporous membrane. By the use of a four-component dope composition, substantially isotropic microporous structures in the form of flat sheets or hollow fibers are produced. An improved spinnerette assembly is provided for the production of hollow fibers.

Abstract: Methods and cards for detecting an antigen or antibody in a fluid sample are disclosed. The fluid sample is added to a microreaction vessel containing a slurry suspension of inert particles and a binding partner to the antigen or antibody to be determined. The fluid sample is added to the micro reaction vessel, with one of the antigen and antibody binding partners being carrier bound. The vessel contents are centrifuged, to cause the binding partners to contact each other to form an optically detectable binding complex. The location of the optically detectable complex is observed to determine the presence of the antibody.

Abstract: A patient's health is diagnosed by centrifuging blood samples in a transparent tube, which tube contains one or more groups of particles such as lyposomes or plastic beads of different densities for each group. Each group of density-defined particles carries antigens or antibodies which are specific to a complement antigen or antibody which may be in the blood sample being tested, and which are indicative of the patient's health. A label-tagged antibody which is specific to all bound antibody/antigen couples is added to the blood sample so as to form labelled antibody+antigen-antibody complexes (AAAC) in the blood sample. Upon centrifugation, the complexed particles will settle out in different areas in the tube according to the respective density of the particles, and the degree of label emission of the particle layers can enable qualitative or quantitative analyses of the blood sample to be made.

Abstract: The present invention includes novel digoxin assays employing a capture reagent, involving a first binding member conjugated to a polymeric anion substance, and a solid phase material containing a reaction site comprising a polymeric cation substance having a nitrogen content of at least about two percent. A test sample suspected of containing the analyte of interest may be contacted with the capture reagent to form a charged capture reagent/analyte complex. The complex is then contacted to the oppositely charged solid phase to attract, attach, and immobilize the capture reagent/analyte complex.

Abstract: An affinity column antibody purification method using a synthetic hCG analyte-analog insolubilized on a support material. The immobilized hCG analyte-analogs are peptide sequences which duplicate or mimic the determinants formed by the amino acid residues of the C-terminus peptide sequence or portions or variants thereof. The antibodies produced according to the present invention are useful in immunoassays for hCG.