Abstract: A reinforced biological sealant is disclosed. The sealant includes a fibrinogen composition adapted to be applied to a wound, and a solid thrombin composition layered on the fibrinogen film. At least one of the fibrinogen or thrombin compositions comprises a reinforcement filler. Means are provided for activating formation of a fibrin mesh from the fibrinogen and thrombin compositions, thereby effecting hermetization and hemostasis of the wound.

Abstract: An apparatus for dispensing reagent spheres from a vial includes a housing with an inlet through which the reagent spheres are received from the vial. Within the housing is a dispensing tube which forms a passageway for the reagent spheres and which has a first relatively large section in communication with the inlet and a funnel section in which the passageway reduces in cross section to a narrower linearizing section. The cross sectional area of the linearizing section is only slightly larger than one of the reagent spheres being dispensed. A metering shaft extends across and blocks the linearizing section of the passageway. The metering shaft has a depression for conveying one reagent sphere at a time between portions of linearizing section when the metering shaft is rotated 180 degrees. A gear on the metering shaft meshes with teeth on a plunger which is slidably mounted to the housing.

Abstract: A method and preparation for the storage and delivery of purified reagents is disclosed. In one aspect, the preparation comprises an amount of a first wax carrier, the first wax carrier having a first melting point, and an amount of a first reagent, wherein first reagent is a substantially purified preparation of at least one biological or chemical reagent. The first wax carrier and the first reagent are combined to form a solid first reagent portion. The solid mixture is combined with a second reagent portion comprised of at least one biological or chemical reagent in an inactive form.

Abstract: Reagents have been prepared from water-insoluble polymeric particles to which are covalently attached avidin, biotin or an avidin or biotin derivative. The polymeric particles comprise a polymer on at least the outer surface which is derived from at least one ethylenically unsaturated monomer having a reactive activated 2-substituted ethylsulfonyl, vinylsulfonyl or active halogen atom. Covalent attachment of avidin, biotin or an avidin or biotin derivative is effected either directly or indirectly through these reactive groups. The resulting reagent is useful in analytical elements and various analytical methods including agglutination and sandwich assays. The immobilized avidin, biotin or derivative can be used to complex with the corresponding biotin or avidin molecule which may be conjugated to a compound of biological interest.

Abstract: A nucleic acid is rapidly extracted from whole blood or a peripheral blood mononuclear cell (PBMC) fraction thereof. Extraction from the PBMC fraction is accomplished by heating the fraction at or near the boiling point of water for a few minutes and recovering the extracted nucleic acid. This rapid method is particularly useful for extracting DNA for the detection of genetic diseases or infectious agents, such as HIV-I. Whole blood can likewise be heated after it is mixed with a salt solution containing a polysaccharide, such as dextran. The extracted nucleic acid is then recovered from the heated mixture. Nucleic acids extracted in this way are available for amplification using a polymerase chain reaction. Where the presence of a specific gene is to be determined for diagnostic purposes, it can be extracted as described above and subjected to suitable amplification and detection steps.

Abstract: Water soluble polymers are useful in combination with cobalt(III) redox reagents. When incorporated with the polymers, the cobalt(III) reagents exhibit improved sensitivity compared to fresh solutions of the reagents. In preferred embodiments, the cobalt(III) reagents are coated on a support using the water soluble polymer as a binder. Small areas of the coated support are then cut out and placed in a buffer solution to provide a working reagent solution. The solution is particularly useful in the testing of urine for significant bacteriuria.

Abstract: A method of synthesizing double-stranded DNA sequences is disclosed.

Abstract: Certain reducible compounds are useful in analytical compositions, elements and methods, e.g. for assays of bacterial cells. These compounds comprise a moiety which provides a detectable species (e.g. a dye) when released from the compound in an environment of pH 9 or less (i.e. physiological pH). Structurally, the reducible compounds are aromatic derivatives or quinones having suitable substituents which promote varying amounts of moiety release at physiological pH. When reduced at about pH 7, the preferred compounds release at least 50% of the available detectable species within 30 minutes.

Abstract: Disclosed herein is an assay useful for the quantitative determination of hemoglobin in whole blood. This assay utilizes a multizone element comprising a registration zone comprising particulate barium sulfate distributed in a "blush" polymer, and a spreading zone having a void volume and an average pore size (e.g. greater than 5 microns) effective to accommodate whole blood. The element also contains an interactive composition capable of converting substantially all forms of hemoglobin into a detectable end product. One particularly useful interactive composition comprises a hemoglobin oxidizing agent (e.g. ferricyanide) and thiocyanate. Another useful interactive composition comprises an ionic surfactant, e.g. sodium octyl sulfate or sodium dodecyl sulfate.

Abstract: Certain reducible compounds are useful in analytical compositions, elements and methods, e.g. for assays of bacterial cells. These compounds comprise a moiety which provides a detectable species (e.g. a dye) when released from the compound in an environment of pH 9 or less (i.e. physiological pH). Structurally, the reducible compounds are aromatic derivatives or quinones having suitable substituents which promote varying amounts of moiety release at physiological pH. When reduced at about pH 7, the preferred compounds release at least 50% of the available detectable species within 30 minutes.

Abstract: Fluorescent labels comprise a polysaccharide bound to a polymeric particle which contains a fluorescent rare earth chelate. These labels can be attached to any of a variety of physiologically reactive species to provide labeled species which have improved stability in aqueous solutions. The labeled species are particularly useful in specific binding assays to determine an immunologically reactive ligand, e.g. a hapten, in either solution or dry analytical techniques.

Abstract: A multilayer analytical element for the determination of a clinically significant enzyme analyte comprises a photosensitive compound (e.g. a photosensitive dye or dye precursor) and a filter layer containing one or more filter dyes. The filter layer is situated in the element such that incident radiation used to detect a density change resulting from interaction of the analyte and the photosensitive compound passes through the filter layer before it reaches the photosensitive compound. The use of the filter layer inhibits premature changes in the photosensitive compound caused by incident radiation. This element is particularly useful for the determination of creatine kinase or one of its isoenzymes, e.g. creatine kinase-MB.

Abstract: Fluorescent labels comprise a polysaccharide bound to a polymeric particle which contains a fluorescent rare earth chelate. These labels can be attached to any of a variety of physiologically reactive species to provide labeled species which have improved stability in aqueous solutions. The labeled species are particularly useful in specific binding assays to determine an immunologically reactive ligand, e.g. a hapten, in either solution or dry analytical techniques.