Abstract: Indicators for the detection of thio groups are disclosed together with processes for the preparation of such indicators.

Abstract: A lancet assembly includes a reusable base unit that defines a handle for a lancet assembly and houses a biasing mechanism for driving a lancet into the finger of a user. The base unit includes a spring biased hammer that once cocked, can be released to drive a lancet. A lancet is included in a disposable end cap that may be releasible attached to one end of the base unit. The end cap includes integral resilience spring fingers that maintain the lancet completely within the end cap before and after use, and functions to return the lancet after engagement of the lancet and hammer. The end cap can be rotated to orient the end cap relative to a user's finger to control the depth of penetration of the lancet into the user's finger.

Abstract: The present invention relates generally to an analytical reagent test strip for assaying fluid samples. The reagent test strip of this invention has a self-indicating format which provides accurate and reliable results without the need for a color chart or instrument analysis. In the preferred embodiment of this invention, reagent threads are incorporated into and protrude through a polymer housing. The threads are placed in a particular pattern whereby different colored configurations will occur in response to different concentrations of analyte in a sample. The present invention is accurate, reliable and convenient to use.

Abstract: Test compositions, indicators, and test device are provided which are capable of generating different hues at different analyte concentrations. The compositions are capable of generating a yellow hue in situ. Visual tests for clinically important analytes, such as glucose, are determined by use of two independent catalytic systems which are reactive with reduced nicotinamide adenine dinucleotide to produce a range of hues; the particular hue produced depending on the concentration of the analyte. The invention provides a test device for the determination of analyte, e.g. glucose, in body fluid which exhibits a rainbow of hues, the particular final hue produced depending on the analyte concentration.

Abstract: A method and apparatus for determining lithium ion concentrations in an aqueous sample are provided wherein the selectivity is improved by the addition of orotic acid. The orotic acid precipitates sodium and potassium ions which can interfere with the lithium ion determination.

Abstract: Indicators for the detection of thio groups are disclosed together with processes for the preparation of such indicators.

Abstract: A new and improved method and composition for determining the presence and concentration of low to trace amounts of proteins, such as albumin, in a test sample, such as urine. The method includes using a reagent composition capable of interacting with low to trace amounts of proteins to produce a visually or instrumentally detectable and/or measurable response. The method can be used in wet assays or in dry test strip assays, wherein the reagent composition is incorporating into a carrier matrix. The new and improved reagent composition, comprising a dye, such as a polyhydroxybenzenesulfonephthalein-type indicator, like pyrocatechol violet; a tungstate, such as ammonium tungstate; and, if necessary, a suitable buffer, is incorporated into the carrier matrix to provide sufficient sensitivity to low to trace protein levels and sufficient color resolution between low to trace protein levels, thereby affording an accurate and trustworthy protein assay of test samples having a low protein concentration.

Abstract: A new and improved test device and method of determining the presence and concentration of fructosamines in a test sample. The test device includes a test pad comprising a carrier matrix incorporating an indicator reagent composition capable of interacting with fructosamines to produce a detectable or measurable response. The carrier matrix of the device includes a bibulous matrix, such as filter paper, or a nonbibulous matrix, such as a polymeric film. In addition, a new and improved indicator reagent composition comprising a dye, such as tetrazolium violet; a suitable buffer; and an accelerator compound is incorporated into the carrier matrix to provide a test pad demonstrating sufficient color resolution and having sufficient sensitivity to fructosamines in a test sample. Therefore, a fast, more accurate and trustworthy fructosamine assay of a liquid test sample, such as whole blood or serum, is achieved.

Abstract: The present invention is directed to an agent and method for eliminating ascorbate interference in reagent systems, particularly assay systems using oxidase/peroxidase coupled reactions or similar type redox chemistry. The present invention can also be used in reagent systems involving enzyme/substrate reactions in which the substrate is sensitive to reductants such as ascorbate. The agents of this invention comprise water insoluble cerium (IV) compounds.

Abstract: The present invention relates to a process for troublefree, i.e. flaw-free and uniform, coating of a support which can accept a large amount of electrostatic charge, such as, for example, polycarbonate foils, with a solution of fully reacted polyurethane in organic solvents, more precisely after prior coating of the polycarbonate foil with an organic solution of the sodium salt of polystyrenesulphonic acid.

Abstract: A disposable, inexpensive electrode for an electrochemical sensor includes a laminated anode and a laminated cathode. The anode is a film substrate with anodic material such as platinum deposited on the substrate. The cathode is also a film substrate with cathodic material such as silver deposited on the substrate. The anode and cathode can be laminated with an intermediate layer of dielectric material. A working surface is provided on the electrode and defined, in part, by the anode and cathode. One procedure for defining the working surface is to fabricate spaced openings in the cathode film and the layer of dielectric material. The openings in the cathode film and dielectrical layer are aligned and the exposed surfaces of the anode and cathode define the working area. An enzyme, such as glucose oxidase, is bonded to the exposed anode and a membrane is applied over the working area and enzyme. The membrane is preferably a silicone water-based elastomer.

Abstract: In a sealable thermoplastic plastics material container for diagnostic test strips, the lid of the container is joined to the container wall via a tear strip and via a hinge piece formed by an extension of the tear strip. The tear strip extends round the circumference of the container apart from the width of the hinge piece.

Abstract: Indicators for the detection of thio groups are disclosed together with processes for the preparation of such indicators.

Abstract: An optical transmission spectrometer for transmission measurements of absorbing and scattering samples includes light sources mounted parallel to each other in a holder. The beams of light eminating from the light sources are directed through a beam-combiner. The beam-combiner includes a first refractive surface at an angle of incidence of 45.degree.. The first refractive surface refracts light toward a common axis. The beam-combiner includes a second refractive surface parallel to the first refractive surface for refracting the beam of light along a common axis parallel to the original direction of the beam of light. The beam-combiner can include additional refractive surfaces for other beams of light to combine the beams of light into a primary beam. The includes a collimating tube extending along the common axis for baffling stray light and directing the primary beam through a sample.