Abstract: Disclosed are methods for conducting assays of samples, such as whole blood, that may contain cells or other particulate matter. Also disclosed are systems, devices, equipment, kits and reagents for use in such methods. One advantage of certain disclosed methods and systems is the ability to rapidly measure the concentration of an analyte of interest in blood plasma from a whole blood sample without blood separation and hematocrit correction.

Abstract: In the present invention cells are placed in a multiwell plate and grown. When the assay is to be performed, one uses gravity to wash away any unbound ligands rather than vacuum or centrifugation. The cells are then examined to detect the bound ligand. To perform the washing step(s) the plate is placed into a carrier plate having open wells in register with the wells of the filter plate or one may use a wicking device or an underdrain attached to the bottom of the filter plate. Sufficient wash liquid is added to allow for filtration by the effect of gravity to occur. Cells are retained within the wells at a rate of 4 times that of other rapid methods.

Abstract: Bodily fluid is analyzed for the presence of drugs of a selected panel of drugs in a simultaneous assay in which sample of the fluid is incubated with additional amounts of all drugs of the panel, antibodies specific to each of the drugs of the panel, and microparticles, the microparticles being divided into subsets, one subset for each drug in the panel and each subset distinguishable from the others. The incubation is performed in a liquid medium in which competitive binding occurs, the drugs in the sample competing with those added to the assay medium for binding to the antibodies. In one procedure, the added drugs are pre-coupled to the microparticles while the antibodies are not, and the incubation is followed by further incubating the microparticles with labeled ligands that have affinity for the antibodies.

Abstract: The present invention discloses a method of purifying bivalent antibodies or antibody fragments that are active at both Fab sites from a source of antibodies or antibody fragments using a non-chromatographic method that includes inducing the formation of cyclic immunoglobulin aggregates by addition of multivalent hapten to a salt solution of soluble antibodies or antibody fragments, wherein the multivalent hapten possesses a linker between the two haptens effective to prevent the binding of both haptens of the ligand to the same antibody or antibody fragment.

Abstract: Assay systems and specialized antibodies for the detection and quantitation of troponin I and troponin T in body fluids as an indicator of myocardial infarction are disclosed. Troponin I and T exist in various conformations and the ratios of monomeric troponin I and T and the binary and ternary complexes, as well as which form of troponin present in the blood, may be related to the metabolic state of the heart. Disclosed are systems to determine the presence of a troponin form or a group of troponin forms in whole blood, serum or plasma samples. Disclosed is a method for improving the recovery of troponin I or T from a surface used in immunoassays. Also disclosed are antibodies which recognize unbound troponin forms, the forms of troponin in binary complexes, the ternary complex of troponin I, T and C, and the conformations of troponin I having intramolecularly oxidized and reduced cysteines.

Abstract: Disclosed are methods for detecting protein complexes of sigma factors and interacting proteins in a sample containing Mycobacterium tuberculosis. Such methods are useful for the diagnosis and/or monitoring of tuberculosis in a subject. Also disclosed are methods for screening compounds that affect the interaction of one or more sigma factors with one or more interacting proteins.

Abstract: The present invention, in some aspects, relates to systems and methods for determining oxidized proteins, including nitrosylated proteins such as S-nitrosylated proteins. The systems and methods of the invention can be used in vitro (e.g., in cell or tissue culture) or in vivo. For instance, in some cases, the invention can be used to spatially determine the location and/or concentration of oxidized proteins within cells and/or tissues (e.g., through visual detection). In one set of embodiments, a nitrosylated or otherwise oxidized moiety on a protein may be reacted with a detection entity, which may be, for example, fluorescent, radioactive, electron-dense, able to bind to a signaling entity or a binding partner in order to produce a signal, etc. In some embodiments, other moieties on the protein may be altered or blocked before reaction of the protein with the detection entity.

Abstract: A method and kit for assaying a cell sample for the presence of at least a threshold number of cells of a given type are disclosed. The kit includes an assay device having a sample chamber for receiving the cell sample and an elongate collection chamber containing a selected-density and/or viscosity medium and having along its length, a plurality of cell-collection regions, and particles which are capable of specific attachment to cells of the selected cell type, and which are effective, when attached to the cells, to increase the density or magnetic susceptibility of the cells. In operation, particle-bound cells and particles in the cell sample are drawn through the elongate collection chamber under the influence of a gravitational or selected centrifugal or magnetic-field force until the particle-bound cells and particles completely fill successive cell-collection regions in the collection chamber.

Abstract: A method of assaying nucleotide receptor P2X7 pore activity in white blood cells contained within a mixed cell sample is provided comprising labeling white blood cells with a white blood cell-specific label; depolarizing the labeled white blood cells with an isotonic depolarizing solution; contacting the labeled white blood cells with dye and a P2X7 agonist in an amount sufficient to activate P2X7 pore activity; contacting the labeled white blood cells with a divalent cation in an amount sufficient to deactivate P2X7 pore activity; and analyzing dye uptake whereby P2X7 pore activity is quantified by the amount of dye taken up in labeled white blood cells treated with the P2X7 agonist relative to labeled white blood cells in the absence of said P2X7 agonist, said P2X7 pore activity being corrected for sample age and by subtraction of P2X7 pore activity contributed by nonviable white blood cells.

Abstract: In the present invention cells are placed in a multiwell plate and grown. When the assay is to be performed, one uses gravity to wash away any unbound ligands rather than vacuum or centrifugation. The cells are then examined to detect the bound ligand. To perform the washing step(s) the plate is placed into a carrier plate having open wells in register with the wells of the filter plate or one may use a wicking device or an underdrain attached to the bottom of the filter plate. Sufficient wash liquid is added to allow for filtration by the effect of gravity to occur. Cells are retained within the wells at a rate of 4 times that of other rapid methods.

Abstract: Bodily fluid is analyzed for the presence of drugs of a selected panel of drugs in a simultaneous assay in which sample of the fluid is incubated with additional amounts of all drugs of the panel, antibodies specific to each of the drugs of the panel, and microparticles, the microparticles being divided into subsets, one subset for each drug in the panel and each subset distinguishable from the others. The incubation is performed in a liquid medium in which competitive binding occurs, the drugs in the sample competing with those added to the assay medium for binding to the antibodies. In one procedure, the added drugs are pre-coupled to the microparticles while the antibodies are not, and the incubation is followed by further incubating the microparticles with labeled ligands that have affinity for the antibodies.

Abstract: Whole cell, simultaneous target and drug-target assay using differentially labeled antibodies and flow cytometry. First antibody binds to total target and second antibody binds to the drug binding site of the target, thus drug binding will competitively inhibit the second antibody allowing for a competitive inhibition assay of drug-target binding. The assay allows for whole cell analysis and even analysis of mixed populations of cells, yet provides detailed kinetic assessment of drug activity.

Abstract: The enumeration of cells in fluids by flow cytometry is widely used across many disciplines such as assessment of leukocyte subsets in different bodily fluids or of bacterial contamination in environmental samples, food products and bodily fluids. For many applications the cost, size and complexity of the instruments prevents wider use, for example, CD4 analysis in HIV monitoring in resource-poor countries. The novel device, methods and algorithms disclosed herein largely overcome these limitations. Briefly, all cells in a biological sample are fluorescently labeled, but only the target cells are also magnetically labeled. The labeled sample, in a chamber or cuvet, is placed between two wedge-shaped magnets to selectively move the magnetically labeled cells to the observation surface of the cuvet. An LED illuminates the cells and a CCD camera captures the images of the fluorescent light emitted by the target cells.

Abstract: New applications for the use of distinguishable particulate labels available in a variety of hues and sized in the submicron range are described. These applications include profiling of cellular components, obtaining secretion patterns, identifying a multiplicity of components in chromatographic or electrophoretic techniques and identification of desired immunoglobulin secreting cells.

Abstract: The present invention provides methods, diagnostic assays, and diagnostic kits based on said methods, to determine levels of immunosuppressive complexes containing immunosuppressive drugs tacrolimus, sirolimus and cyclosporine A separately and in combination, formed in the blood of a drug-treated patient or in a patient candidate to immunosuppressive drug therapy. These methods, assays and kits are especially useful when using automated systems.

Abstract: A process for the detection of antibodies in a test sample by preparing a suspension of erythrocytes with a test serum or plasma by mixing a test serum or plasma with erythrocytes; incubating the suspension of erythrocytes at a temperature of from 37° C. to 45° C. to bind any antibodies in the test serum or plasma to the surface of said erythrocytes; combining the suspension of erythrocytes with an amount of a solution of a macromolecule which is effective to agglutinate the erythrocytes; packing the resultant red cell agglutinates by centrifuging the suspension of erythrocytes; and, determining the presence of anti-erythrocyte antibodies by observing if antibody-dependent erythrocyte agglutination has occurred.

Abstract: A negative isolation method for separately isolating preparations of Th1 and Th2 helper lymphocytes from peripheral blood mononuclear cells involving the use of novel combinations of monoclonal antibodies to separately sequester specific Th1 and Th2 lymphocytes and contaminating leukocytes and erythrocytes, adding a magnetic colloid to the cells, and using a magnetic column for fractionation of Th1 and Th2 cells. Imbalances in the relative numbers of Th1 and Th2 lymphocytes can be used in the diagnosis and prognosis of human diseases.

Abstract: Elevated number of Circulating Endothelial Cells (CEC) have been implicated in disease conditions associated with the formation or destruction of blood vessels such as acute coronary syndrome, thrombocytopenic purpura, sickle cell disease, sepsis, lupus, nephrotic syndromes, rejection of organ transplants, surgical trauma and cancer. This invention provides a method for assessing the levels of CEC which vary between different studies using a sensitive enrichment, imaging, and enumberation analysis. CD146 is one of the most specific endothelium-associated cell-surface antigens which can be used in image cytometry. CEC analysis provides an essential tool in prognostic/diagnostic evaluation in the clinic.

Abstract: The present invention provides compositions and methods for treating or preventing antibody mediated graft rejection and blood typing.

Abstract: The invention provides nanoparticles and nanoparticle conjugates comprising one or more redox-active species, methods of making nanoparticles and nanoparticle conjugates, and methods for using nanoparticles and nanoparticle conjugates, for example, as diagnostic agents for the detection of various analytes.

Abstract: A method and apparatus for use in a flow through assay process is disclosed. The method is characterized by a “pre-incubation step” in which the sample which is to be analysed (typically for the presence of a particular protein), and a detection analyte (typically one or more antibodies bound to colloidal gold or a fluorescent tag) which is known to bind to the particular protein may bind together for a desired period of time. This pre-incubation step occurs before the mixture of sample and detection analyte come into contact with a capture analyte bound to a membrane. The provision of the pre-incubation step has the effect of both improving the sensitivity of the assay and reducing the volume of sample required for an assay. An apparatus for carrying out the method is disclosed defining a pre-incubation chamber for receiving the sample and detection analyte having a base defined by a membrane and a second membrane to which a capture analyte is bound.

Abstract: A sample analysis device is provided in which a target component to be analyzed is prevented from being contaminated by a sample itself, which can be formed in an appropriate size, and which has excellent operability. In a sample analysis device 1 in which a sample is to be held in a porous sheet 13, supporting films 11 and 12 are stuck on front and rear faces of the porous sheet 13, respectively, and a sample supply hole 14 is formed in a part of the supporting films.

Abstract: The methods and reagents described in this invention are used to analyze circulating tumor cells, clusters, fragments, and debris. Analysis is performed with a number of platforms, including flow cytometry and the CellSpotter® fluorescent microscopy imaging system. Analyzing damaged cells has shown to be important. However, there are two sources of damage: in vivo and in vitro. Damage in vivo occurs by apoptosis, necrosis, or immune response. Damage in vitro occurs during sample acquisition, handling, transport, processing, or analysis. It is therefore desirable to confine, reduce, eliminate, or at least qualify in vitro damage to prevent it from interfering in analysis. Described herein are methods to diagnose, monitor, and screen disease based on circulating rare cells, including malignancy as determined by CTC, clusters, fragments, and debris. Also provided are kits for assaying biological specimens using these methods.

Abstract: A diagnostic test kit that provides an integrated system for accurately detecting a test analyte over a broad range of possible concentrations is provided. One feature of the integrated system is that it is capable of indicating whether an analyte is within the “hook effect” region. Based on this indication, a technique may be selected for correlating a measured signal intensity to an analyte concentration or range of concentrations. For example, when it is determined that the test sample falls outside the “hook effect” region, the analyte concentration may be determined using one portion of a dose response curve. On the other hand, when it is determined that the test sample falls within the “hook effect” concentration, the analyte concentration may be determined using another portion of the dose response curve. Alternatively, the sample may simply be diluted for re-performing the assay.

Abstract: A blood crossmatching apparatus, kit and methods for testing the compatibility of mammals for blood transfusion. Particulate layers in the apparatus allow nonagglutinated red blood cells to permeate through, while agglutinated red blood cells cannot. The apparatus also has a density solution. The density solution separates white blood cells from red blood cells in the whole blood when centrifuged, without lysing the red blood cells. Thus, the apparatus can be used to test whole blood.

Abstract: Analytes using an active assay may be detected by introducing an analyte solution containing a plurality of analytes to a lacquered membrane. The lacquered membrane may be a membrane having at least one surface treated with a layer of polymers. The lacquered membrane may be semi-permeable to nonanalytes. The layer of polymers may include cross-linked polymers. A plurality of probe molecules may be arrayed and immobilized on the lacquered membrane. An external force may be applied to the analyte solution to move the analytes towards the lacquered membrane. Movement may cause some or all of the analytes to bind to the lacquered membrane. In cases where probe molecules are presented, some or all of the analytes may bind to probe molecules. The direction of the external force may be reversed to remove unbound or weakly bound analytes. Bound analytes may be detected using known detection types.

Abstract: The present invention is directed to apparatuses and methods for reducing the content of albumin in serum, plasma and/or blood samples. The apparatuses comprise an insoluble support with a ligand attached thereto. According to certain embodiments of the invention, the ligand is a bromosulfophthalein, Cibacron Blue or Warfarin ligand or salts or esters thereof. Also provided are methods of making the apparatus, as well as kits and albumin-depleted samples produced by the methods of the present invention.

Abstract: The present invention provides methods for identifying and/or enriching fetal cells from maternal blood, using as fetal cell markers the antibodies that the mother produces against paternally inherited fetal antigens. The fetal cell-maternal antibody complexes are identified and isolated using labelled agents that bind to the maternal antibodies. The present invention also provides fetal cells, isolated by use of said maternal antibodies, as a source of fetal DNA for prenatal genetic diagnosis of the fetus.

Abstract: Methods of detecting and/or quantifying an IgE antibody present in a liquid sample. The IgE antibody is specific to a ligand in the form of an antigen, an antibody, or a hapten. These methods can be used for monitoring and evaluating the immunological status of a subject.

Abstract: The invention relates to methods for the determination of pharmacological properties of substances, such as, e.g., chemical substances. The invention also relates to methods and kits for use in the determination of the free fraction, fu, of pharmacologically active compounds in aqueous solutions and serum. The invention also relates to the above methods in which solid particles, coated with a lipophilic medium, are used.

Abstract: A method for measuring an analyte in a whole blood sample comprising the steps of (1) bringing the whole blood sample into contact with a first substance which is carried on an insoluble carrier and specifically binds to the analyte to be measured and a second substance which is labeled with an alkaline phosphatase and specifically binds to the analyte to be measured, and (2) measuring a resulting complex on the basis of an enzyme reaction of the alkaline phosphatase, the measuring step (2) being carried out in the presence of an inhibitor of endogenous alkaline phosphatases, is disclosed.

Abstract: The invention relates to a method for detecting disease-associated autoantibodies, which recognize extracellular structures of G protein-coupled receptors, and to the use of peptides, which comprise these loops or fragments thereof, for treating autoimmune diseases.

Abstract: The present invention relates to methods for detecting or quantifying an analyte in a test sample including providing at least one test mixture including a test sample, at least one marker complex, wherein each marker complex includes a particle, a marker, and one member of a coupling group, a first binding material selected to bind to a portion of the analyte, a second binding material selected to bind with a portion of the analyte other than the portion of the analyte for which the first binding material is selected, analyte analog, and/or marker conjugate. The at least one test mixture is passed through a membrane. The amount of marker on the membrane is detected and correlated to the presence or amount of analyte in the test sample.

Abstract: An immunological or immunohematological assay system is disclosed that includes a filter vessel capable of containing an assay sample, an incubator, a sample separation system, an image acquisition system, and a robotic pipettor. The immunological assay system may also include a washer. Also disclosed is an immunological assay method that includes the steps of placing a immunological assay sample in a filter vessel, which includes a filter, adding testing reagents to the filter vessel, incubating the sample and reagent mixture in the filter vessel, separating the sample and reagent mixture in the filter vessel into components above and below the filter, and analyzing the filter vessel to determine the presence of interactions between the sample and reagents.

Abstract: A test strip configured for the detection of an analyte in a fluid sample and methods for manufacturing and for using the same. The test strip comprises a first flow matrix and a second flow matrix sequentially arranged to form an interface therebetween. The first flow matrix comprises a detection composition movably bound thereto, wherein the detection composition when exposed to the analyte produces at least one detectable product and wherein the first and second solid matrices are selected so as to accumulate the at least one detectable product at the interface between the two matrices, when the fluid sample travels from the first flow matrix to the second flow matrix.

Abstract: A method for analyzing a biological sample by antibody profiling for identifying forensic samples or for detecting the presence of an analyte. In an embodiment of the invention, the analyte is a drug, such as marijuana, Cocaine (crystalline tropane alkaloid), methamphetamine, methyltestosterone, or mesterolone. The method comprises attaching antigens to a surface of a solid support in a preselected pattern to form an array wherein locations of the antigens are known; contacting the array with the biological sample such that a portion of antibodies in the sample reacts with and binds to the antigens in the array to form immune complexes; washing away antibodies that do form immune complexes; and detecting the immune complexes, to form an antibody profile. Forensic samples are identified by comparing a sample from an unknown source with a sample from a known source.

Abstract: The invention provides methods and compositions for simultaneously detecting the activation state of a plurality of proteins in single cells using flow cytometry. The invention further provides methods and compositions of screening for bioactive agents capable of coordinately modulating the activity of a plurality of proteins in single cells. The methods and compositions can be used to determine the protein activation profile of a cell for predicting or diagnosing a disease state, and for monitoring treatment of a disease state.

Abstract: Test strips designed to prevent or reduce false results when measuring the condition of a sample are provided. The test strips can be used for analysis of samples by methods including electrical and optical measurements. The reagent test strips and methods are particularly suited for use in the detection of blood coagulation.

Abstract: A membrane-based assay device for detecting the presence or quantity of an analyte residing in a test sample is provided. The device utilizes a self-calibrated magnetic binding assay format (e.g., sandwich, competitive, etc.) that includes detection probes capable of generating a detection signal (e.g., fluorescent non-magnetic particles) and calibration probes capable of generating a calibration signal (e.g., fluorescent magnetic particles). The amount of the analyte within the test sample is proportional (e.g., directly or inversely) to the intensity of the detection signal calibrated by the intensity of the calibration signal. It has been discovered that the fluidics-based device of the present invention provides an accurate, inexpensive, and readily controllable method of determining the presence of an analyte in a test sample.

Abstract: A solid-phase immunoassay for 6-keto-Prostaglandin F1?, the stable hydrolysis product of prostacyclin (Prostaglandin I2) is disclosed. Prostacyclin, a potent vasodilator with anti-platelet and anti-proliferative properties is an effective treatment for primary pulmonary hypertension and pulmonary arterial hypertension associated with scleroderma and scleroderma-like syndrome. Levels of 6-keto-Prostaglandin F1? can be directly correlated with levels of prostacyclin. Therefore, 6-keto-Prostaglandin F1? has become the indicator of choice to measure prostacyclin levels. The single step immunoassay for 6-keto-Prostaglandin F1? uses the bioluminescent protein, aequorin as a label. Analyte-label conjugates were constructed by linking the carboxyl group of 6-keto-Prostaglandin F1? and lysine residues of aequorin by chemical conjugation methods. The binding properties of 6-keto-Prostaglandin F1? towards its antibody and the bioluminescent properties of aequorin are retained in the conjugate.

Abstract: A latex reagent for analyzing adiponectin, comprising a suspension of latex particles carrying a substance which specifically binds to adiponectin, is disclosed. Further, a method for analyzing adiponectin, comprising (1) obtaining a biological liquid possibly containing adiponectin, and (2) bringing the biological liquid, while maintaining the state in which the biological liquid is obtained, into contact with a suspension of latex particles carrying a substance which specifically binds to adiponectin, and optically analyzing a degree of latex-particles-agglutination, is disclosed. According to the latex reagent and the method for analyzing adiponectin, a predilution or pretreatment of the biological liquid to be analyzed is not necessary. Further, the analysis can be performed rapidly and conveniently, and facilities therefor are not limited.

Abstract: An analytical test element for blood analyses is provided having an application site and a microfluidic channel structure in fluid communication with the application site. The channel structure includes at least first and second analytical channels for receiving first and second portions of a blood sample applied to the application site. The first analytical channel includes a first analytical site to determine the total haemoglobin value (Hb) of the blood sample. The second analytical channel includes a second analytical site to determine a glycohaemoglobin value (HbA1c) of the blood sample.

Abstract: The instant invention provides an economical flow-through method for determining amount of target proteins in a sample. An antibody preparation (whether polyclonal or monoclonal, or any equivalent specific binding agent) is used to capture and thus enrich a specific monitor peptide (a specific peptide fragment of a protein to be quantitated in a proteolytic digest of a complex protein sample) and an internal standard peptide (the same chemical structure but including stable isotope labels). Upon elution into a suitable mass spectrometer, the natural (sample derived) and internal standard (isotope labeled) peptides are quantitated, and their measured abundance ratio used to calculate the abundance of the monitor peptide, and its parent protein, in the initial sample.

Abstract: The present invention provides a magnetic sifter that is small in scale, enables three-dimensional flow in a direction normal to the substrate, allows relatively higher capture rates and higher flow rates, and provides a relatively easy method of releasing captured biomolecules. The magnetic sifter includes at least one substrate. Each substrate contains a plurality of slits, each of which extends through the substrate. The sifter also includes a plurality of magnets attached to the bottom surface of the substrate. These magnets are located proximal to the openings of the slits. An electromagnetic source controls the magnitude and direction of magnetic field gradient generated by the magnets. Either one device may be used, or multiple devices may be used in series. In addition, the magnetic sifter may be used in connection with a detection chamber.

Abstract: Assay systems and specialized antibodies for the detection and quantitation of troponin I and troponin T in body fluids as an indicator of myocardial infarction. Since troponin I and T exist in various conformations in the blood, the ratios of the monomeric troponin I an T and the binary and ternary complexes, as well as which form of troponin present in the blood, may be related to the metabolic state of the heart. Disclosed is a system to determine the presence of a troponin form or a group of troponin forms in a sample of whole blood, serum or plasma. Disclosed is a stabilized composition of troponin; the stabilized composition can comprise a stabilized composition of troponin I, wherein the troponin I is oxidized, the troponin I can be unbound or the troponin I can be in a complex.

Abstract: The present invention provides methods, diagnostic assays, and diagnostic kits based on said methods, to determine levels of immunosuppressive complexes containing immunosuppressive drugs tacrolimus, sirolimus and cyclosporine A separately and in combination, formed in the blood of a drug-treated patient or in a patient candidate to immunosuppressive drug therapy. These methods, assays and kits are especially useful when using automated systems.

Abstract: A method to determine specificity of ligand binding includes comparing a solid phase carrier first extract obtained by pre-treating a sample with a ligand-immobilized solid phase carrier and a solid phase carrier second extract obtained by treating the pretreated sample again with a ligand-immobilized solid phase carrier in terms of the proteins contained therein, and identifying a protein whose content is remarkably decreased in the second extract compared to the first extract, in order to solve 1) the problem of the solubility of subject ligand, 2) the problem of the non-specific protein-denaturing effect of the subject ligand added, and the like, in antagonism experiments in target search using an affinity resin.

Abstract: Heterogeneous assays for different analytes in a single biological sample are performed simultaneously in a multiplexed assay that combines flow cytometry with the use of magnetic particles as the solid phase and yields an individual result for each analyte. The particles are distinguishable from each other by characteristics that permit them to be differentiated into groups, each group carrying an assay reagent bonded to the particle surface that is distinct from the assay reagents of particles in other groups. The magnetic particles facilitate separation of the solid and liquid phases, permitting the assays to be performed by automated equipment. Assays are also disclosed for the simultaneous detection of antibodies of different classes and a common antigen specificity or of a common class and different antigen specificities.

Abstract: A method of rapidly assaying nucleotide receptor P2X7 pore activity in white blood cells contained within a blood sample. A method according to the invention includes the steps of: (a) labeling the white blood cells with a white blood cell-specific label; (b) depolarizing the labeled white blood cells with an isotonic depolarizing solution; (c) contacting the labeled white blood cells with a dye and a P2X7 agonist in an amount sufficient to activate nucleotide receptor P2X7 pore activity; (d) contacting the labeled white blood cells with a divalent cation in an amount sufficient to deactivate nucleotide receptor P2X7 pore activity; and (e) analyzing dye uptake in labeled white blood cells whereby nucleotide receptor P2X7 pore activity is quantified by the amount of dye taken up in labeled white blood cells treated with P2X7 agonist relative to labeled white blood cells in the absence of P2X7 agonist.

Abstract: The present invention is directed to methods for quantitatively measuring biomolecules by using magnetic nanoparticles. Through the use of the magnetic nanoparticles and the bioprobes coated to the magnetic nanoparticles, the biomolecules conjugated with the bioprobes result in the formation of particle clusters. By measuring the changes in magnetic properties resulting from the existence of the bio-targets, the amount of the bio-targets in a sample to be tested can be measured.