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. 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: A diagnostic method and associated test kit for detecting an analyte residing in a test sample is provided. A sample membrane is utilized having a collection region and a detection region, the collection region having a known saturation volume for the intended test sample. A barrier is defined between the collection region and the detection region. The collection region is saturated with the test sample having a volume of less than about 100 microliters so that a known volume of the test sample is contained in the collection region. The barrier is removed from between the collection region and detection region of the membrane and a diluent is supplied to the collection region of the membrane to facilitate flow of the test sample from the collection region to the detection region of the membrane.

Abstract: A membrane array used to detect one or more analytes from a small sample of fluid with high sensitivity is provided. The membrane array can be employed in various analytical devices and is especially useful for identifying analytes from whole blood with minimal or negligible background interference.

Abstract: Described herein is an analyte detection device and method related to a portable instrument suitable for point-of-care analyses. In some embodiments, a portable instrument may include a disposable cartridge, an optical detector, a sample collection device and/or sample reservoir, reagent delivery systems, fluid delivery systems, one or more channels, and/or waste reservoirs. Use of a portable instrument may reduce the hazard to an operator by reducing an operator's contact with a sample for analysis. The device is capable of obtaining diagnostic information using cellular- and/or particle-based analyses and may be used in conjunction with membrane- and/or particle-based analysis cartridges. Analytes, including proteins and cells and/or microbes may be detected using the membrane and/or particle based analysis system.

Abstract: There is described an affinity-chromatography assay system comprising with an immobilized component containing a bio-reagent and a flowable component containing a complimentary bio-reagent characterized in that the immobilized component is supported on a dip strip or planar surface and the flowable component is adapted to flow down the dip strip of high density. There is also described a method of conducting an affinity-chromatography assay which comprises the use of such an assay system.

Abstract: A flow-through assay device for detecting the presence or quantity of an analyte residing in a test sample is provided. The device utilizes a detection zone and compensation zone within which are immobilized capture reagents. The present inventor has discovered that the presence of a compensation zone may enable the detection of an analyte over extended concentration ranges. In particular, the compensation zone facilitates the binding of probes that would otherwise bind within the interior of assay device or that would exhibit “self-quenching”.

Abstract: Dipstick tests for detecting analyte are described. In a preferred embodiment, a multiple biotinylated antibody capable of binding analyte is bound to an anti-biotin antibody labelled with colloidal gold and wicked up the dipstick with test solution thought to contain analyte. Complex formed between analyte, biotinylated anti-analyte antibody, and colloidal gold labelled anti-biotin antibody is captured at a capture zone of the dipstick. Presence of colloidal gold label at the capture zone indicates the presence of analyte in the test solution. The sensitivity of analyte detection using such methods is an order of magnitude higher than for comparable methods in which biotinylated anti-analyte antibody bound to analyte is wicked up the dipstick in a first step, and a colloidal gold labelled anti-biotin antibody is wicked up the dipstick in a separate step. Kits for performing the tests of the invention are also described.

Abstract: A method and system for performing biochemical detection or analysis on micro- and nano-scale subcellular component within a single biological cell is provided. An integrated platform device and method to perform the biochemical analysis is also provided.

Abstract: A liquid applicator for applying a liquid sample to a liquid receiving surface is disclosed. The liquid applicator comprises a bibulous line to hold a first predetermined volume of liquid for application to a liquid receiving surface. A second predetermined volume less than or equal to the first predetermined volume is applied to the liquid receiving surface in a substantially uniform and consistent pattern. Systems and methods for using embodiments of the liquid applicators are also disclosed.

Abstract: A Plasma or serum separation membrane that enables omitting centrifugal separation, is free from hemolysis attributed to destruction of red blood cells and realizes easy and rapid separation of plasma or serum from blood; and a filter apparatus including the plasma or serum separation membrane. In particular, a plasma or serum separation membrane being a membrane for separation of plasma or serum from blood and having a void ratio of 30% or below; and a filter apparatus comprising a filter member capable of attaining movement of plasma swifter than movement of blood cells and a plasma or serum separation membrane connected in series with a rear side of the filter member.

Abstract: A rapid immunoassay method and apparatus for detecting foot and mouth disease virus are disclosed. The method and test device permit pen-side testing of animals and provide test results within a relatively short time period. In a preferred embodiment, the method and apparatus provide a means for differentiating between FMDV-infected and FMDV-vaccinated animals.

Abstract: Labels and methods of producing labels for use in clinical, analytical and pharmaceutical development assays are provided. Labels may comprise shape-encoded particles which may be coupled to ligands such as DNA, RNA and antibodies, where different shapes are used to identify which ligand(s) are present. Labels may also comprise reflectors, including retroreflectors and retroreflectors susceptible to analyte-dependent assembly for efficient homogeneous assays.

Abstract: More particularly, the present invention relates to a method for the detection of a target, e.g. pathogen in a human body fluid wherein a body fluid sample is collected with a swab member.

Abstract: A flow-through assay device for detecting the presence or quantity of an analyte residing in a test sample is provided. The device utilizes a scavenging zone that contains a capture reagent for the analyte of interest. The capture reagent may capture a quantity of the analyte that is less than or equal to a predefined base quantity of the analyte, such as a quantity considered “normal” for a particular test sample. Thus, the capture reagent is able to prevent some of the analyte from being detected. In this manner, the sensitivity of the assay device may be reduced in a simple, inexpensive, yet effective manner.

Abstract: A method for patterning a one or more biomolecules on a substrate that includes coating the substrate with a coating of the one or more biomolecules, applying a laser to the coating, and ablating a portion of the one or more biomolecules with the laser in a predetermined pattern.

Abstract: A rapid assay concentration device. In one form, the device includes a substrate and a plurality of elongated membranes on the substrate. At least one capture zone is formed in each membrane. Each capture zone is responsive to the presence of a target chemical in the fluid. Capture zones on different membranes have different threshold levels of response to the chemical. In a method for monitoring temporal changes of analyte levels in a source multiple test devices are provided, with each device including a plurality of regions. Each region is responsive at a different sensitivity level to indicate presence of the analyte. A source sample is brought into contact with a first of the test devices to determine whether the source contains a level of analyte sufficient to induce a response thereto in one or more of the test unit regions.

Abstract: The invention is directed to a method and device for simultaneously testing a sample for the presence, absence, and/or amounts of one or more of a plurality of selected analytes. The invention includes, in one aspect, a device for detecting or quantitating a plurality of different analytes in a liquid sample. Each chamber may include an analyte-specific reagent effective to react with a selected analyte that may be present in the sample, and detection means for detecting the signal. Also disclosed are methods utilizing the device.

Abstract: The systems of the invention include test cells with a first sorbent material defining a first flow path for a solution, a second sorbent material defining a second flow path distinct from the first flow path for a sample, and a test line or test site with immobilized antigens or antibodies or other ligand binding molecules such as aptamers, nucleic acids, etc. located at the junction of the first and second sorbent materials. The first and second sorbent strips touch each other at the test site location.

Abstract: A structure for controlling fluid flow from a sample receiving pad into a lateral flow assay test strip, including: a lateral flow assay test strip; a sample pad abutting the lateral flow assay test strip; a pinch wall positioned to direct fluid flow from the sample pad to the lateral flow assay test strip; a top support structure positioned on top of the test strip; and a bottom support structure positioned underneath the test strip, wherein each of the top and bottom support structures comprise a plurality of separate spaced-apart support ribs positioned along the length of the test strip.

Abstract: A self-contained apparatus using a gravitationally encouraged, interrupted, downward, diffusive and programmed flow of fluid to provide for rapid confirmatory immunological testing (“RCIT”) in, for example, a clinical, point-of-care setting. A fluid specimen such as blood, saliva or urine is deposited into a first chamber carrying a source of conjugate having mobilizable binding members such as immunographic antigens or antibodies specific to the condition being tested conjugated to a detectable label such as colloidal gold. The specimen is premixed with a first measured, reactive mix buffer solution carried within an openable tank. The specimen and solution are temporarily held within an incubation reservoir formed behind a dam made from porous, diffusive material.