Abstract: A method of detecting creatinine in body fluids using an indicator which produces a fluorescent response when oxidized in the presence of a copperII/creatinine complex. A preferred indicator is 4-(1-methylhydrazino)-7-nitro benzooxadiazole (MNBDH).

Abstract: A method of detecting creatinine in body fluids using an indicator which produces a fluorescent response when oxidized in the presence of a copperII/creatinine complex. A preferred indicator is 4-(1-methylhydrazino)-7-nitro benzooxadiazole (MNBDH).

Abstract: Disclosed is a method for the immobilization of an analyte such as deoxypyridinium (DPD) onto a solid support. The method involves binding an antigen-amino acid-deoxypyridinium complex to the support via an anti-antigen binding partner located in a capture zone of the solid support. Preferably, the support is nitrocellulose and the antigen has the fluorescein structure.

Abstract: Disclosed is an improvement to the technique for immobilizing an analyte onto a solid surface for use in a competitive immunoassay. The improvement involves immobilizing the analyte on the solid surface by reacting the analyte or derivative thereof with polyethylene glycol which has been functionalized with a group which is reactive with the analyte contacting the resulting conjugate with the solid surface to thereby immobilize the analyte.

Abstract: Disclosed is a method for the chemical synthesis of deoxypyridinoline (DPD). The synthesis involves the preparation of a protected 3-hydroxypyridinium starting with a N.alpha.-protected lysine and a 5,6-epoxy-2-N-protected-O-protected-(2S)-2-aminohexanoate with subsequent deprotection to provide the desired DPD.

Abstract: Test devices are disclosed which are useful for determining glucose or occult blood comprising a carrier matrix, glucose oxidase, an indicator system and a glucose derivative that upon addition of water hydrolizes to produce glucose.

Abstract: The present invention involves the use of certain indole sulfonates in a test control method for the Ehrlich reagent used in diagnostic tests for urobilinogen. The indole sulfonates exhibit unique solubility characteristics which facilitate their application to dry carrier matrixes with subsequent rehydration during their use in the test control method.

Abstract: 2-Benzothiazolyl tetrazolium salt compounds have been found to be characterized by a reflectance spectrum exhibiting an extended plateau above about 600-650 nm. Such compounds are useful as chromogenic indicators for reducing substances such as NADH. The reflectance plateau confers improved accuracy to analytical assays, particularly for the determination of analytes of medical diagnostic significance, in which a colorimetric response on a reagent carrier matrix is measured by reflectance.

Abstract: Disclosed are sulfonate and phosphonate salts of tetrazolium compounds whose enhanced solubility in various solvents renders them particularly suitable for use as redox indicators in dry reagent, diagnostic test systems.

Abstract: The present invention relates to a chromogenic benzoisothiazolone polymer derivative for measuring the presence or appearance of thiols in an aqueous system.

Abstract: A process for measuring the presence or appearance of thiols in aqueous system, the process involving contacting the aqueous system with a chromogenic thiol indicating benzoisothiazolone derivative and then observing chromophoric changes due to thiol mediated reduction of the benzoisothiazolone derivative wherein the changes are proportional to the amount or rate of appearance of the thiols in the aqueous system.

Abstract: Newly synthesized chromogenic thiol-indicating benzoisothiazolone derivatives having the structure: ##STR1## where R.sup.1, R.sup.2 and R.sup.3 are as defined in the specification, are useful in the detection of thiols, particularly in an aqueous system. This process comprises contacting the aqueous system with a chromogenic thiol-indicating benzoisothiazolone derivative as described herein. Chromophoric changes due to thiol-mediated reduction of the benzothiazolone derivative then occur. Such changes can be in a solution or on an indicator surface in contact or having been in contact with the aqueous system. The chromophoric changes, due to a bathochromic shift in characteristic light absorption upon reduction of the benzoisothiazolone derivative, are proportional to the amount or rate of appearance of thiols in the aqueous system.

Abstract: Newly synthesized chromogenic thiol-indicating benzoisthiazolone derivatives having the structure: ##STR1## where R.sup.1, R.sup.2 and R.sup.3 are as defined in the specification, are useful in the detection of thiols, particularly in an aqueous system. This process comprises contacting the aqueous system with a chromogenic thiol-indicating benzoisothiazolone derivative as described herein. Chromophoric changes due to thiol-mediated reduction of the benzothiazolone derivative then occur. Such changes can be in a solution or on an indicator surface in contact or having been in contact with the aqueous system. The chromophoric changes, due to a bathochromic shift in characteristics light absorption upon reduction of the benzoisothiazolone derivative, are proportional to the amount or rate of appearance of thiols in the aqueous system.

Abstract: General classes of 2-thiazolyl tetrazolium salt compounds have been found to be characterized by a reflectance spectrum exhibiting an extended plateau above about 600-650 nm. Such compounds are useful as chromogenic indicators for reducing substances such as NADH. The reflectance plateau confers improved accuracy to analytical assays, particularly for the determination of analytes of medical diagnostic significance, in which a colorimetric response on a reagent carrier matrix is measured by reflectance.

Abstract: Optical indicator chalcogen (selenide or sulfide) compounds responsive to oxidants, e.g., hydrogen peroxide, and a method for using such indicators. Upon oxidation the resulting intermediate undergoes spontaneous elimination of the chalcogen residue to yield a signal compound which provides an optical signal such as fluorescence. Preferred fluorogenic indicator compounds are 3-chalcogen-3,4-dihydrocoumarin derivatives and 3-chalcogen-3,4-dihydro-2-quinolone derivatives. Such indicator compounds provide highly fluorescent products upon oxidation by hydrogen peroxide and are useful in analytical systems which generate hydrogen peroxide in response to the analyte under determination.

Abstract: Optical indicator chalcogen (selenide or sulfide) compounds responsive to oxidants, e.g., hydrogen peroxide, and methods for preparing and using such indicators. Upon oxidation the resulting intermediate undergoes spontaneous elimination of the chalcogen residue to yield a signal compound which provides an optical signal such as fluorescence. Preferred fluorogenic indicator compounds are 3-chalcogen-3,4-dihydrocoumarin derivatives and 3-chalcogen-3,4-dihydro-2-quinolone derivatives. Such indicator compounds provide highly fluorescent products upon oxidation by hydrogen peroxide and are useful in analytical systems which generate hydrogen peroxide in response to the analyte under determination.

Abstract: Test devices are disclosed which are useful for determining glucose or occult blood comprising a carrier matrix, glucose oxidase, an indicator system and a glucose derivative that upon addition of water hydrolizes to produce glucose.

Abstract: Immobilization of nucleic acids, e.g., DNA and RNA, by contact with a solid support comprising nylon whose amide groups have been partially solvolyzed. Solvolysis of the nylon support can be accomplished by treatment with an alkylating agent such as a trialkyloxonium salt under anhydrous conditions followed by addition of water. The immobilized nucleic acid is particularly useful as an immobilized probe in hybridization assays to detect specific polynucleotide sequences in a test sample.

Abstract: Fluorogenic indicator compounds responsive to the presence of hydrogen peroxide and methods and test compositions for determining hydrogen peroxide in a test sample. Preferred indicator compounds are 3,4-dihydrocoumarin derivatives and 3,4-dihydro-2-quinolone derivatives, especially those having a dialkylamino group at the 7-position. Such particularly preferred compounds are of the formula: ##STR1## wherein R.sup.1 is hydrogen, cyano, or --COOR.sup.6, --CONHR.sup.6 or --CON(R.sup.6).sub.2 where R.sup.6 is hydrogen, alkyl, alkenyl, or aryl; R.sup.3 and R.sup.4 are lower alkyl; and Y is .dbd.0 or .dbd.N--R.sup.5 where R.sup.5 is hydrogen or lower alkyl. The indicator compounds yield highly fluorescent products upon oxidation by hydrogen peroxide in the presence of a peroxidatively active substance and are useful in analytical systems which generate hydrogen peroxide in response to an analyte under determination in a test sample.

Abstract: Optical indicator chalcogen (selenide or sulfide) compounds responsive to oxidants, e.g., hydrogen peroxide, and methods for preparing and using such indicators. Upon oxidation the resulting intermediate undergoes spontaneous elimination of the chalcogen residue to yield a signal compound which provides an optical signal such as fluorescence. Preferred fluorogenic indicator compounds are 3-chalcogen-3,4-dihydrocoumarin derivatives and 3-chalcogen-3,4-dihydro-2-quinolone derivatives. Such indicator compounds provide highly fluorescent products upon oxidation by hydrogen peroxide and are useful in analytical systems which generate hydrogen peroxide in response to the analyte under determination.