Abstract:
Nucleic acid probes and protein probes are disclosed. The nucleic acid probe comprises a probe polynucleotide, a charged hapten label, and a binding moiety. The protein probe comprises a probe protein, a charged hapten label and a binding moiety. The charged hpaten label joined to the binding moiety can comprise a negatively charged sulfophenylhydrazine tag compound. Polyclonal antibodies and monoclonal antibodies with specific affinity for the charged hapten labels are disclosed as are hybridomas capable of making the monoclonal antibodies. Methods and kits are disclosed for making the nucleic acid probes, making the protein probes, detecting a capture polynucleotide of the nucleic acid probe and detecting a capture molecule of the protein probe.
Abstract:
A method and specimen slide for obtaining fecal occult blood specimens. The slide includes first and second portions each including front and back panels. The first portion includes one or more apertures formed through its front panel which exposes a reagent-carrying sheet and the back panel of the first portion includes a flap that may be opened for the application of additional reagents to the back of the sheet. The second portion includes an aperture in its front panel and a flap formed in its back panel. A sheet is carried between the front and back panels of the second portion onto which a fecal specimen may be smeared. The sheet includes pre-perforated removable portions that may be easily accessed through the flap. As an alternative embodiment, the back panel of the second portion may include a removable tab to which is fixed the specimen sheet. The tab and specimen sheet may be removed for easy access to the removable portions of the specimen sheet.
Abstract:
Specific binding assays for measuring the concentration of an analyte in a sample involve forming a complex comprising a solid support, the analyte or an analogue of the analyte, and an enzyme. The enzyme is used to cleave non-isotopic labels that are directly detectable from a substrate/label conjugate to provide a plurality of released labels in the free state, which are then separated from conjugate containing unreleased label. The released labels are detected for measuring the concentration of the analyte in the sample. Preferably the analyte or analogue is connected to the solid support by a cleavable bond, so that the enzyme can be separated from the solid support for use in the enzymatic cleaving of labels from the conjugate. This preferred version reduces the adverse effect of non-specific binding on the sensitivity and accuracy of the assay.
Abstract:
A competitive binding assay for vitamin B12 in a test sample gives a steep dose-response curve in the clinically significant concentration regions, yielding great accuracy. The assay uses immobilized vitamin B12 to compete with the vitamin B12 in the test sample for a binding partner. The quantity of the binding partner bound to the immobilized vitamin B12 can be measured and is inversely proportional to the concentration of free vitamin B12 in the test sample. The binding partner is typically biotinylated intrinsic factor prepared so that substantially all the molecules of intrinsic factor are biotinylated and the binding activity of the intrinsic factor for vitamin B12 is not diminished. The bound biotinylated intrinsic factor can then be determined by reacting it with avidin coupled to a reporter group. The reporter group is typically an enzyme such as horseradish peroxidase, but can be another detectable label. The immobilized vitamin B12 is typically bound to a solid support such as diazotized amine-derivatized beads, and can be bound through a protein linker. Other binding partners such as anti-vitamin B12 antibody are also usable. The binding partner can be labeled directly with the reporter group. The method is adaptable to the assay of serum, and methods of inactivating endogenous vitamin B12-binding proteins in serum are described.
Abstract:
The present invention provides an improved rotor for a centrifuge that operates by centrifugal elutriation. The rotor consists of a chamber assembly, a disk assembly, and a quick release mechanism. The chamber assembly is relatively light and it includes one or two separation chambers, tubing and a rotating seal. The disk assembly consists of the relatively heavy support structure. The two piece construction facilitates handling the parts of the rotor that generally need to the autoclaved. The chamber assembly has a novel structure that allows the rotor to easily be configured for operation with one or two chambers. The disk assembly has a unique strain relief that prevents structural cracking. The quick release mechanism is held in the latched position by centrifugal force during operation of the rotor.
Abstract:
A 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 analysis system including an ion selective electrode assembly, a sample container and a transport mechanism. The electrode assembly includes a reference electrode within a reference gel-filled well and ion selective electrodes disposed on an elongated portion of the electrode assembly. The sample container includes a body defining a plurality of reservoirs and a slot retaining an absorbant wiping and/or blotting material. The electrode assembly may be removably fixed relative to the transport mechanism. The transport mechanism includes a support table adapted to receive the sample container. The support table moves relative to the electrode assembly under the control of a cam to sequentially position the elongated portion of the electrode assembly within the reservoirs and the slot of the sample container.
Abstract:
A cold stable liquid reagent system suitable for use in a Jaffe method for the determination of creatinine comprises: a) a homogeneous liquid picric acid component comprising picric acid in an amount of no more than about 35 mM, such that the picric acid component remains visibly homogeneous at a temperature between about 2 to about 8°C for 30 days or more; b) a homogeneous liquid alkaline buffer component comprising: i) an alkaline material in sufficient amount to maintain the pH of the alkaline buffer component at more than about 13, for controlling the pH of the assay ready reagent formed by combining the picric acid and alkaline buffer components; ii) at least one pH buffer material; iii) a detergent for reducing interference by proteins in the Jaffe method; and iv) borate for reducing interference by carbohydrates in the Jaffe method; wherein the alkaline buffer components contains substantially no metallic cations such that the component remains visibly homogeneous at a temperature between about 2 to about 8°C for 30 days or more. Preferably the alkaline material is tetramethylammonium hydroxide, and the detergent is diethanolamine dodecyl sulfate.
Abstract:
This invention relates to a diluting and mixing device which is capable of diluting a first solution to produce a second solution which is mixed with an undiluted third solution, to reproducibly produce a unique series of combined solutions. Each solution in said series of combined solutions may vary only in the concentration of a single (selected) reactant, and typically, each successive solution becomes increasingly more concentrated in the selected reactant. By employing a modification in procedure, each successive solution in said series may become decreasingly less concentrated in the selected reactant. This invention further relates to an automated system comprising the device connected to a stepping motor so as to rapidly and reproducibly produce said series of solutions, said device being further connected to an analyzer means for obtaining chemical, biochemical, or physical chemical data on said series of solutions. This invention especially relates to an embodiment of the device for obtaining kinetic data on enzyme reactions in solutions. The device is useful because it provides a means for rapidly obtaining chemical, biochemical, or physical chemical data on reactions in solution.
Abstract:
A temperature control apparatus for controlling the temperature of a plurality of cuvettes (32) consisting of an annular sealed chamber (20) containing a refrigerant (120), means (18) fixed to the sealed chamber (20) for receiving the sample cuvettes (32), a heater (44, 76) in thermal contact with the sealed chamber, and a temperature sensor (52, 78) in thermal contact with the sealed chamber (20). The sealed chamber (20) may include a plurality of thermally conductive posts (28) fixed to the chamber (20), the spacing between adjacent ones of the posts (28) being adapted to receive the sample cuvettes (32).