Abstract: An imaging method and apparatus are provided, including a light source emitting a polarized light beam, and an optical assembly including a control layer and/or a light reflection surface. The control layer advantageously allows for control over the properties of a generated evanescent wave to optimize an image of a specimen array within the evanescent wave. The light reflection surface includes coupling means used to couple a receptor/capture agent advantageously allowing for flexible control over receptor specific regions.

Abstract: Methods are disclosed for producing electrochemiluminescence by electrochemically oxidizing an acridan compound at an electrode in the presence of a peroxide. Maintaining a sufficiently positive potential results in continuous oxidation of the acridan compound to an acridinium compound which reacts with peroxide to produce the luminescence. Light emission can be reversibly and repeatedly cycled on and off by sweeping the potential between two values. The acridan compounds can be provided with a labeling group for linking to an analyte or analyte binding partner. The present electrochemiluminescent reaction can find use in assay methods for detecting analytes by immunoassays and nucleic acid assays.

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: A biosensor includes a substrate with a receptive material layer of radiation-absorbing member (RAM)-tagged biomolecules disposed thereon. The receptive material is specific for an analyte of interest. A pattern of active and deactivated areas of the receptive material are defined in the receptive material layer by a masking process wherein areas are exposed through a mask with a light source to induce deactivation.

Abstract: Methods are provided for detecting biomolecular interactions. The use of labels is not required and the methods can be performed in a high-throughput manner. The invention also relates to optical devices.

Abstract: This invention provides solid phase specific binding lateral flow assay methods, devices and kits for quantitating high and low molecular weight analytes. The methods and devices of the invention employ labelled reagents which are either analyte analogs or complementary specific binding pair members for the analyte and a novel arrangement of capture zones comprising immobilized specific binding substances for either the analyte or the labelled reagent to effect bound from unbound labelled reagent as a function of analyte concentration. The capture zones are disposed on a non-bibulous matrix defining a flow path from a sample receiving zone to the capture zone. The devices of this invention also include multilane flow paths and multiple capture zones to quantitate analyte.

Abstract: Solid-state colorimetric biosensors having sensory groups and interdendritic cross-linking segments of alternating conjugated double and triple bonds are prepared by intermolecular polymerization of diacetylene-functionalized dendritic polymer precursors. The polymerization process may be used to form solid films that are capable of indicating the presence of an analyte by a detectable change in color. The disclosed solid-state colorimetric biosensors may exhibit excellent stability at elevated temperatures and in the presence of organic solvents, and due to the dendritic architecture and high density of sensing functionality achieve high sensitivity to analytes.

Abstract: This invention provides a novel fluorescent particle including a core or carrier particle having on its surface a plurality of smaller polymeric particles or nanoparticles, which are stained with different fluorescent dyes. When excited by a light source they are capable of giving off multiple fluorescent emissions simultaneously, which is useful for multiplexed analysis of a plurality of analytes in a sample. The coupled complex particles carrying on their surface fluorescent nanoparticles, methods of preparing such polymer particles, and various applications and methods of using such particles are claimed.

Abstract: A device for detecting a compound in a sample includes a substrate and a self-assembled monolayer. The substrate includes a support with a metallized top surface, and the self-assembled monolayer includes an alkanethiol attached to the metallized top surface of the substrate and having a functional group that reversibly or irreversibly interacts with the compound. A liquid crystal is disposed on the self-assembled monolayer opposite the side of the self-assembled monolayer attached to the metallized top surface of the substrate. The liquid crystal includes a moiety that interacts with the functional group of the alkanethiol. When the compound is present in a sample that that contacts the self-assembled monolayer, the orientation of the liquid crystal is altered.

Abstract: Disclosed are sensors for use in testing biological, biochemical, chemical or environmental samples, and methods of making and using the same.

Abstract: A method of forming a liquid crystal device, includes: contacting an aqueous solution comprising a surfactant and a receptor molecule with a top surface of a liquid crystal. The liquid crystal is in a holding compartment of a substrate, and the receptor molecule is adsorbed on the top surface of the liquid crystal forming an interface between the liquid crystal and the aqueous solution. The receptor molecule is different than the surfactant. A method of detecting a compound in a flowing stream includes passing an aqueous solution over a top surface of a liquid crystal in a holding compartment of a substrate. The method also includes determining whether a change in the orientation of the liquid crystal occurs as the aqueous solution is passed over the top surface of the liquid crystal. A change in the orientation of the liquid crystal indicates the presence of the compound in the flowing stream.

Abstract: Methods and compositions are provided for detecting changes in membrane potential in membranes biological systems. In one aspect, the method comprises; a) providing a living cell with a first reagent comprising a charged hydrophobic molecule which is typically a fluorescence resonance energy transfer (FRET) acceptor or donor, or is a quencher and is capable of redistributing within the membrane of a biological membrane in response to changes in the potential across the membrane; b) providing the cell with a second reagent that can label the first face or the second face of a biological membrane within the cell; c) detecting light emission from the first reagent or the second reagent. One aspect of this method involves monitoring membrane potential changes in subcellular organelle membranes in a living cells. Another aspect of the invention is the use of certain embodiments of the method for the screening of test chemicals for activity to modulate the activity of a target ion channel.

Abstract: An electrochemical test device is provided for determining the presence or concentration of an analyte in an aqueous fluid sample. The electrochemical test device includes a working electrode and a counter electrode made of an amorphous semiconductor material. The working electrode is overlaid with a reagent capable of reacting with an analyte to produce a measurable change in potential which can be correlated to the concentration of the analyte in the fluid sample. The test device optionally contains a reference electrode made of an amorphous semiconductor material having a reference material on the reference electrode. The test device electrodes can be constructed on a flexible film substrate, such as a polymeric film or a metal foil coated with a non-conductive coating.

Abstract: Methods and compositions are provided for determining the potential of a membrane. In one aspect, the method comprises: (a) introducing a first reagent comprising a hydrophobic fluorescent ion capable of redistributing from a first face of the membrane to a second face of the membrane in response to changes in the potential of the membrane, as described by the Nernst equation, (b) introducing a second reagent which labels the first face or the second face of the membrane, which second reagent comprises a chromophore capable of undergoing energy transfer by either (i) donating excited state energy to the fluorescent ion, or (ii) accepting excited state energy from the fluorescent ion, (c) exposing the membrane to radiation; (d) measuring energy transfer between the fluorescent ion and the second reagent, and (e) relating the energy transfer to the membrane potential. Energy transfer is typically measured by fluorescence resonance energy transfer.

Abstract: An immunochemical assay device for determining the presence of NT-proBNP alone or conjunctively with Cardiac Troponin I comprising a base member, an array disposed on the base member, and at least one assay indicia zone. The array comprises (i) a reservoir pad to receive sample liquid, (ii) a wicking membrane, and (iii) at least one filter zone interposed between the wicking membrane and the reservoir pad. The filter zone being operable to permit passage of any specific immunocomplex to the wicking membrane while impeding passage of larger components.

Abstract: An analytical test device useful for example in pregnancy testing, comprises a hollow casing (500) constructed of moisture-impervious solid material, such as plastics materials, containing a dry porous carrier (510) which communicates indirectly with the exterior of the casing via a bibulous sample receiving member (506) which protrudes from the casing such that a liquid test sample can be applied to the receiving member and permeate therefrom to the porous carrier, the carrier containing in a first zone a labelled specific binding reagent is freely mobile within the porous carrier when in the moist state, and in a second zone spatially distinct from the first zone unlabelled specific binding reagent for the same analyte which unlabelled reagent is permanently immobilised on the carrier material and is therefore not mobile in the moist state, the two zones being arranged such that liquid sample applied to the porous carrier can permeate via the first zone into the second zone, and the device incorporating mea

Abstract: An apparatus to measure micro-forces includes a cantilever palette with a set of cantilever array blocks. Each cantilever array block includes a set of cantilevers, with each cantilever including a set of cantilever fingers surrounded by a frame with frame fingers. The cantilever fingers and the frame fingers form a diffraction grating. Each cantilever array block is configured to be responsive to a predetermined micro-force, such that cantilevers of the cantilever array block deflect in the presence of the predetermined micro-force, which causes the diffraction grating to diffract light and thereby provide a visual indication of the presence of the predetermined micro-force.

Abstract: Methods, compositions and kits are disclosed. The methods are directed to determining the presence of one or more analytes in a sample suspected of containing any one of a plurality of the analytes. A combination is provided comprising in a medium (i) the sample, (ii) a binding partner for each of the analytes, (iii) for each of the analytes, a first reagent comprising a member of a signal producing system, a ligand and an analyte analog, and (iv) a second reagent comprising a binding partner for the ligand. The binding of the binding partner for the ligand is affected by the presence of an analyte and alters the amount of signal produced by the member of the signal producing system. The signal thus is modulated if one or more of the analytes are present in the sample. The amount of the signal is determined and is related to the presence of one or more of the analytes in the sample. The method may be homogeneous or heterogeneous.

Abstract: The invention provides a methods for fabricating colorimetric resonant reflection biosensors.

Abstract: A diagnostic test unit is provided. The test unit comprises a stem having a first end and a second end, the stem defining at least one flow channel extending between the first end and the second end. A swab is disposed at the first end of the stem, the swab being configured to collect a test sample derived from a biological source that is suspected of containing an analyte. The test unit also comprises a fluid chamber configured to contain a fluid, wherein the fluid chamber is in fluid communication with the swab via the flow channel. The test unit also comprises a rupturable seal that inhibits leakage of the fluid from the fluid chamber prior to use, and an assay for detecting the presence or absence of the analyte. The assay is in fluid communication with the swab, the flow channel, and the fluid chamber.

Abstract: An analyzer useful in determining the presence of an analyte using a diffraction based sensing device and methods and systems using this device. The present invention may be used with a variety of different diffraction-based diagnostic methods and systems. The analyzer enhances the accuracy and/or usefulness of these devices in detecting analytes, while providing more ease-of-use and convenience to the user. The analyzer may include a light source, a photodiode, a microprocessor and a display system for informing the user of the result. Other features include mirrors, lenses, a sample holder, and a mask for blocking out some light. The analyzer and related method and system may be used in a large number of environments, including commercial, professional, and individual.

Abstract: Bioelectronic devices for the detection of estrogen include a collection of eukaryotic cells which harbor a recombinant lux gene from a high temperature microorganism wherein the gene is operably linked with a heterologous promoter gene. A detectable light-emitting lux gene product is expressed in the presence of the estrogen and detected by the device.

Abstract: A device for detecting the presence of an antigen including (1) a cell having antibodies which are expressed on the surface of the cell and are specific for the antigen to be detected, where binding of the antigen to the antibodies results in an increase in calcium concentration in the cytosol of the cell, the cell further having a emitter molecule which, in response to the increased calcium concentration in the cytosol, emits a photon; (2) a liquid medium for receiving the antigen and in which the cell is immersed; and (3) an optical detector arranged for receiving the photon emitted from the cell.

Abstract: An enhanced diffraction based biosensor system and method are provided for detecting an analyte of interest in a test medium. The system incorporates at least one additional detection tag substance with the analyte of interest, the tag emitting a measurable parameter that is different from optical diffraction characteristics of the analyte. The biosensor may be a “fluoroptical” system wherein the detection tag is a fluorescence emitting substance, including fluorescent-labeled diffraction enhancing elements. The enhanced diffraction biosensor system may determine the presence of analytes in biological fluids both qualitatively and quantitatively.

Abstract: A coplanar waveguide biosensor and methods of use include a coplanar waveguide transmission line and a sample containment structure. The coplanar waveguide transmission line is operable to support the propagation of an electromagnetic signal and includes a signal line and one or more spaced apart ground elements. The signal line is configured to conduct a time-varying voltage, and the one or more ground elements are configured to maintain a time-invariant voltage, a detection region being formed between a portion of the signal line and a portion of at least one of the one or more ground elements. Detection methods are improved through the enhancement of the electric field in the detection region via impedance discontinuities in the signal line and ground elements. The sample containment structure intersects the detection region of the coplanar waveguide transmission line and includes a cavity configured to hold 1 ml or less of sample solution within the detection region.

Abstract: The present invention provides a method of detecting human antibodies in a sera solution. The invention also provides a method of quantitating anti-glycolipid antibody levels in solutions. The invention provides a method of diagnosing disease states, including neurological diseases, by quantitating a subject's antibody levels.

Abstract: Methods and compositions are provided for detecting biomolecular interactions. The use of labels is not required and the methods can be performed in a high-throughput manner. The invention also provides optical devices useful as narrow band filters.

Abstract: Assays for detecting molecular modifications such as phosphate modifications and the presence and/or activity of enzymes and other agents involved in facilitating or otherwise regulating such modifications.

Abstract: A screening device for performing an immunoassay test to detect the presence of a compound in a body fluid. The device includes a holder for removably receiving a membrane to which the fluid has been applied. A light is directed to the membrane. A photodetector measures the concentration of the light reflected back from the membrane. Specifically, the concentrations of reflected light from a control zone and a test zone are measured. Signals representative of the measured light concentrations are applied to a processor. If a specified concentration of predetermined light from a control zone on the membrane is detected, the processor considers the test to be successful. In the test is successful, the processor, based upon the measured concentration of reflected light from the test zone, generates data representative of the presence of the compound.

Abstract: The present invention provides novel microfluidic devices and methods that are useful for performing high-throughput screening assays. In particular, the devices and methods of the invention are useful in screening large numbers of different compounds for their effects on a variety of chemical, and preferably, biochemical systems.

Abstract: A test device (20) for detecting human blood includes a strip (22) having an introduction station (24), a test station (26), and a control station (28) disposed in spaced apart relationship. The test sample introduction station (24) has labeled antihuman Hb antibodies, the test station (26) has immobilized antihuman Hb antibodies, and the control station has immobilized polyclonal antibodies. A test sample (500) is deposited at the introduction station (24). If human hemoglobin is present in the test sample (500), a colored line will appear at the test station (26) and at the control station (28). If no human hemoglobin is present in the test sample (500), a colored line will only appear at the control station (28).

Abstract: Graphitic nanotubes, which include tubular fullerenes (commonly called “buckytubes”) and fibrils, which are functionalized by chemical substitution, are used as solid supports in electrogenerated chemiluminescence assays. The graphitic nanotubes are chemically modified with functional group biomolecules prior to use in an assay. Association of electrochemiluminescent ruthenium complexes with the functional group biomolecule-modified nanotubes permits detection of molecules including nucleic acids, antigens, enzymes, and enzyme substrates by multiple formats.

Abstract: The present invention herein provides the design, synthesis and characterization of compositions comprising asymmetric bolaamphiphilic lipids that form extended polymeric ribbons and wide sheets. These compositions may be doped, or interspersed, with various compounds to fine-tune the fluidity and rigidity of the bolaamphiphilic lipid composition, and promote other morphologies of the composition, including fluid vesicles and truncated flat sheets. Upon an increase in pH these compositions undergo a calorimetric and morphological transformation.

Abstract: An improved multi-layered diagnostic sanitary test strip for receiving a heterogenous fluid, such as whole blood, to test for presence and/or amount of a suspected analyte in the fluid by facilitating a color change in the strip corresponding to the amount of the analyte in the fluid, wherein the test strip includes fluid volume control dams to prevent spillage of the fluid from the strip and a chemical reagent solution that facilitates end-point testing.

Abstract: Novel bipyridyl-osmium complex conjugates and their use in electrochemical assays are described. The redox reversible-osmium complexes can be prepared to exhibit unique reversible redox potentials and can thus be used in combination with other electroactive redox reversible species having redox potentials differing by at least 50 millivolts in electrochemical assays designed for use of multiple electroactive species in the same cell and in the same sample without interference between the two or more redox coupled conjugate systems.

Abstract: Molecular chemical and/or biological sensors that exhibit a very high density of sensing functionality and which are applicable to a wide variety of different analytes, and enable rapid, convenient and economical detection of analytes are prepared by reacting a dendritic polymer with a diacetylene reagent wherein the diacetylene functional groups are subsequently intramolecularly polymerized to form segments having alternating conjugated double and triple bonds. Sensory groups that can bind with an analyte are bonded to the acetylene monomer units to form molecular sensors that produce observable and measurable color changes when an analyte binds with the sensory groups.

Abstract: The present invention provides novel microfluidic devices and methods that are useful for performing high-throughput screening assays. In particular, the devices and methods of the invention are useful in screening large numbers of different compounds for their effects on a variety of chemical, and preferably, biochemical systems.

Abstract: An apparatus for measuring a medical substance where a prism having a high refractive index, a thin metal film formed on one of the surfaces of the prism, a light source for making a light incident upon the thin metal film, and a detector for detecting an incident angle of a light being made incident upon a film on which a plasmon resonance phenomenon is generated on the thin metal film are provided. The medical substance, i.e. antigen as an object to be measured, is fixed to the surface of the thin metal film, and the condition for generating the plasmon resonance phenomenon is varied when a mixture of antibody which is coupled with the medical substance in a specific manner and a sample is made contact with a surface of the thin metal film; and the amount of the medical substance can be detected by recognizing the change with a high sensitivity.

Abstract: Methods, compositions and kits are disclosed. The methods are directed to determining the presence of one or more analytes in a sample suspected of containing any one of a plurality of the analytes. A combination is provided comprising in a medium (i) the sample, (ii) a binding partner for each of the analytes, (iii) for each of the analytes, a first reagent comprising a member of a signal producing system, a ligand and an analyte analog, and (iv) a second reagent comprising a binding partner for the ligand. The binding of the binding partner for the ligand is affected by the presence of an analyte and alters the amount of signal produced by the member of the signal producing system. The signal thus is modulated if one or more of the analytes are present in the sample. The amount of the signal is determined and is related to the presence of one or more of the analytes in the sample. The method may be homogeneous or heterogeneous.

Abstract: The invention provides an apparatus and method for detection of a target molecule. The apparatus includes a probe labeled with a transition metal-ligand complex that hybridizes with the target to form an initial complex, a metal ion for doping the initial complex and forming a final complex, and a potential means for providing a potential to the final complex to produce a detectable signal indicating the presence of the target after redox reaction. The method of the invention teaches the steps of hybridizing a probe with an attached label to the target to produce an initial complex, adding a metal ion to the initial complex to form a final complex and applying a potential to the final complex to produce a measurable signal.

Abstract: The invention relates to analytical methods in which the partition of a labeled substance between a liquid and a solid phase is determined. The assays include solid-phase reagents which can be particulate or monolithic such as, for example, a coated tube. Assays of this type are known per se to the person skilled in the art and include immunoassays and immunometric assays.

Abstract: Methods and apparatus for evanescent light fluoroimmunoassays are disclosed. The apparatus employs a planar waveguide and optionally has multi-well features and improved evanescent field intensity. The preferred biosensor and assay method have the capture molecules immobilized to the waveguide surface by site-specific coupling chemistry. Additionally, the coatings used to immobilize the capture molecules provide reduced non-specific protein adsorption.

Abstract: Imaging apparatus which images the changes in height of reactive spots on the surface of a slide requires the surface roughness of the slide to be small enough to distinguish the changes in height from the roughness features of the slide.

Abstract: The invention relates to assays for measuring ubiquitin ligase activity and for identifying modulators of ubiquitin ligase enzymes.

Abstract: An assay device for determining an analyte in an aqueous sample comprises: (i) an elongate flow matrix (6) allowing lateral transport of fluid therethrough by capillary action, wherein the matrix comprises a liquid application zone (3) and downstream thereof, a detection zone (8) having an immobilized capture agent capable of directly or indirectly binding to said analyte, (ii) a wicking member (13) placed at the downstream end of the flow matrix and having an upstream end and a downstream end, and (iii) a time indicator (14) placed downstream of the detection zone (8) for indicating when liquid applied to the liquid application zone has reached the time indicator. The time indicator comprises an indicator substance or substance combination which is capable of exhibiting a visible color change when hydrated by the aqueous sample.

Abstract: An electrochemical test device is provided for determining the presence or concentration of an analyte in an aqueous fluid sample. The electrochemical test device includes a working electrode and a counter electrode made of an amorphous semiconductor material. The working electrode is overlaid with a reagent capable of reacting with an analyte to produce a measurable change in potential which can be correlated to the concentration of the analyte in the fluid sample. The test device optionally contains a reference electrode made of an amorphous semiconductor material having a reference material on the reference electrode. The test device electrodes can be constructed on a flexible film substrate, such as a polymeric film or a metal foil coated with a non-conductive coating.

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

Abstract: Materials and methods are provided for producing patterned multi-array, multi-specific surfaces for use in diagnostics. The invention provides for electrochemiluminescence methods for detecting or measuring an analyte of interest. It also provides for novel electrodes for ECL assays. Materials and methods are provided for the chemical and/or physical control of conducting domains and reagent deposition for use multiply specific testing procedures.

Abstract: An assay apparatus includes a cell with a working electrode and a sonicating device structurally coupled to the cell for sonication the contents of the cell.

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