Abstract: The present invention provides tangential flow filtration devices and methods for enriching a heterogeneous mixture of blood constituents for leukocytes by removal of non-leukocyte blood constituents. In one particular embodiment the device can provide a composition enriched in monocytes. One embodiment includes a remover unit (1) having a crossflow chamber (3) separated by a microporous filter (5) from a filtrate chamber (4), the remover unit (1) also having a tangential flow inlet (6), a fluid outlet (7) for a fluid enriched in leukocytes and a filtrate outlet (8).

Abstract: Methods for measuring the amount of two or more analytes of interest in a fluid sample, and kits useful in the methods, are disclosed. The methods involve determining a ratio of a detected amount of a single analyte of interest, to the sum of a detected amount of each of the analytes of interest plus a detected amount of a control, wherein the amount of each analyte of interest is directly or inversely related to the ratio for each analyte of interest.

Abstract: Methods for quantitatively measuring the amount of an analyte of interest in a fluid sample, and kits useful in the methods, are disclosed. The methods comprise sandwich assays, and utilize an internal calibration reaction that closely mimics the reaction of test particles by the use of a two-step reaction.

Abstract: Fluorescent pH detector and methods for measuring pH using the fluorescent pH detector.

Abstract: Fluorescent pH detector and methods for measuring pH using the fluorescent pH detector.

Abstract: A modular reader system and method provides for testing a test sample and determining characteristics of the sample. A first test module is configured to perform a first reading on a test sample and produce data regarding the reading. A second test module is configured to perform a second reading of the test sample and produce data regarding the second reading. The first and second test modules are communicatively coupled to a control module. The control module collects the data produced by the first and second test modules and processes the data to determine characteristics of the test sample.

Abstract: Methods for measuring the relative amount of two or more analytes of interest in a fluid sample, as well as kits useful in the methods, are disclosed. The methods involve assays that utilize a solid phase apparatus with a membrane having an application point and at least two sample capture zones having sample capture reagents; analyte binding particles or analyte coated particles; and assessment of a ratio of such particles arrested in capture zones, wherein the ratio is equal to, or inversely equal to, the relative amounts of the analytes of interest in the fluid sample.

Abstract: A sample testing apparatus (100) for use in measuring an analyte in a sample (105) is disclosed. The apparatus includes a sample well (104) for receiving the sample. A solid analyte binding agent (160) is disposed in the sample well. The apparatus further includes a mixing device (156) for mixing the sample with the solid analyte binding agent and a valve (129). The valve is configurable between a closed position for impeding flow of the sample from the sample well and an open position for releasing the sample from the sample well. The apparatus additionally includes a membrane (118) for receiving the sample once released from the sample well, the membrane having a capture reagent (164) adapted to interact with at least one of the analyte, the analyte binding agent, or a complex thereof, to aid in determining the amount of the analyte in the sample.

Abstract: Methods for quantitatively measuring the amount of an analyte of interest in a fluid sample are disclosed. The methods involve providing a membrane having an application point, a contact region comprising analyte-binding particles, a sample capture zone, and a control capture zone, where the contact region is between the application point and the sample capture zone, and the sample capture region is between the contact region and the control capture zone. In the assays, a fluid allows transport components of the assay by capillary action through the contact region, to and through the sample capture zone and subsequently to and through the control capture zone. In a “sandwich assay” embodiment, the amount of analyte in the fluid sample is related to a corrected analyte-binding particle amount, which can be determined, for example, as a ratio of the amount of analyte-binding particles in the sample capture zone and the amount of analyte-binding particles in the control capture zone.

Abstract: Methods for quantitatively measuring the amount of an analyte of interest in a fluid sample are disclosed. The methods involve providing a membrane having an application point, a contact region comprising analyte-binding particles, a sample capture zone, and a control capture zone, where the contact region is between the application point and the sample capture zone, and the sample capture region is between the contact region and the control capture zone. In the assays, a fluid allows transport components of the assay by capillary action through the contact region, to and through the sample capture zone and subsequently to and through the control capture zone. In a “sandwich assay” embodiment, the amount of analyte in the fluid sample is related to a corrected analyte-binding particle amount, which can be determined, for example, as a ratio of the amount of analyte-binding particles in the sample capture zone and the amount of analyte-binding particles in the control capture zone.

Abstract: Methods for quantitatively measuring the amount of an analyte of interest in a fluid sample are disclosed. The methods involve providing a membrane having an application point, a detection zone, and a contact region, where the contact region is between the application point and the detection zone, and has test particles and internal control particles imbedded within it; contacting the application point with the fluid sample; maintaining the membrane under conditions sufficient to allow fluid to transport analyte by capillary action to the contact region, where the analyte binds to the test particles; further maintaining the membrane under conditions sufficient to allow fluid to transport analyte-bound test particles and internal control particles to the detection zone, where they interact with a detection reagent; and detecting the amount of test particles and the amount of internal control particles in the detection zone.

Abstract: An automated sample analysis instrument positively identifies and maintains the identity of a plurality of patient samples contained in individual sample containers. The invention prevents sample misidentification, especially when patient sample must be transferred from one sample container to reaction wells in Microtiter.RTM. plates. Rows of reaction wells in Microtiter.RTM. plates are processed in parallel so the difference in reaction time between any two wells on a plate is four minutes or less. Reaction wells are washed with high-pressure jets of wash solution and are aspirated so as to advantageously utilize fluid meniscus on top of fluid contained in the wells. The apparatus can be adjusted to perform a variety of different ELISA-type tests.

Abstract: The analytical dipstick of the present invention facilitates analyte testing with reduced liquid reagent volumes and provides improved mixing. The dipstick includes an elongated member having a fluid displacing member at one end thereof and a ligand attached to a portion of the elongated member in a region adjacent to the displacing member. The displacing member has a configuration that substantially conforms with the inner side wall of an analytical well in which the dipstick is placed to displace fluid therein. When the displacing member is substantially centered at the bottom of the well, the portion of the dipstick supporting the ligand preferably is spaced from the inner side wall by a distance of at least about twice that between the displacing member and the inner side wall, measured along a line passing through the greatest lateral dimension of the displacing member.

Abstract: A method and system for locating the point P.sub.0 which defines the location of a machine, e.g. an earth moving machine, a surveying or locating machine, etc., in relation to a tract or area of interest by measuring the angles defined by two different sets of reference points selected from at least three reference points that are in known relation to the tract or area.

Abstract: A novel bidentate conjugate has two different chemical moieties, or bidentate members, attached through an adequate spacer moiety. Each bidentate member acts as a small molecule ligand and is capable of specifically binding to a different macromolecular substance. The bidentate members are relatively small molecules, usually less than about 7,000 Daltons in size. The spacer moiety is selected so that both bidentate members can simultaneously bind to their respective specific binding partners. Where the specific binding partners are multivalent, large complexes can be formed. The formation of these complexes can be inhibited by the presence of an unconjugated monovalent bidentate member, such as free analyte from a test sample. The bidentate is of particular use in turbidimetric or nephelometric inhibition immunoassay procedures.

Abstract: A novel bidentate conjugate has two different chemical moieties, or bidentate members, attached through an adequate spacer moiety. Each bidentate member acts as a small molecule ligand and is capable of specifically binding to a different macromolecular substance. The bidentate members are relatively small molecules, usually less than about 7,000 Daltons in size. The spacer moiety is selected so that both bidentate members can simultaneously bind to their respective specific binding partners. Where the specific binding partners are multivalent, large complexes can be formed. The formation of these complexes can be inhibited by the presence of an unconjugated monovalent bidentate member, such as free analyte from a test sample. The bidentate is of particular use in turbidimetric or nephelometric inhibition immunoassay procedures.

Abstract: An automated sample analysis instrument positively identifies and maintains the identity of a plurality of patient samples contained in individual sample containers. The invention prevents sample misidentification, especially when patient sample must be transferred from one sample container to reaction wells in Microtiter.RTM. plates. Rows of reaction wells in Microtiter.RTM. plates are processed in parallel so the difference in reaction time between any two wells on a plate is four minutes or less. Reaction wells are washed with high-pressure jets of wash solution and are aspirated so as to advantageously utilize fluid meniscus on top of fluid contained in the wells. The apparatus can be adjusted to perform a variety of different ELISA-type tests.

Abstract: A system and method for performing a clinical assay, both including the use of a reaction capsule having a hydrophobic membrane which may be repeatedly wetted and rendered hydrophobic. A pressure differential across the membrane causes liquid flow therethrough to be initiated and the hydrophobic state is then achieved by flowing gas through the membrane. The system includes a turntable supporting a plurality of reaction capsules and eccentric means for agitating the turntable and capsules. The turntable is rotated to position the capsules at various processing stations, including sample introduction, reagent introduction, wash, substrate introduction and read stations. A single cylinder two-inlet valve may be used, one inlet connected to liquid and a second inlet connected to a gas source, to provide both liquid and gas flow through the membrane.

Abstract: A power load for use with an underwater spear gun including a casing, explosive material within the casing, the casing having one closed end adapted to open when the explosive material explodes. The closed end is sealed with a sealing compound to prevent water from penetrating the casing. The closed end may be crimped closed or closed by means of a wad or plug of suitable material. The sealing compound may be a silicone rubber or polylvinylchloride which permeates the closed end.

Abstract: A spear gun and a power load for use therewith, the spear gun including a breech, a barrel fixed to the breech, and a spear adapted to be received by a bore within the barrel. The breech includes a chamber for receiving an explosive power load, the chamber being in fluid communication with the bore. The spear is sized to substantially prevent the flow of gas between the spear and the bore and may include a gas restrictor proximate one end to further reduce the flow of gas past the spear. The power load has no projectile and includes an explosive sealed to prevent water damage to the explosive. A line retainer adapted to be carried by the spear includes a plurality of pins urged toward the spear, the pins being adapted to be received in a reduced portion of the spear.