Abstract: Analytical reagents designated "release tags", for labeling molecular species with a highly detectable signal group which can be released in the form of a volatile compound at a desired point in an analytical procedure. In one embodiment, the release tags have the formula(SgCo).sub.x L(Rx).sub.rwherein each Sg is a signal group bearing one or more electronegative substituents, L is any of a wide variety of groups which when attached to a carbonyl group form a readily cleaved linkage, each COL moiety is a release group which upon scission releases signal group Sg in the form of a volative compound, and each Rx is a reactivity group for attaching the release tag compound to a molecular species to be labeled. In a second embodiment, the release tags have the formulaSgReRxwherein Sg and Rx are defined as above and Re is a release group which is an olefin, .alpha.-hydroxy ketone or vicinal diol. Conjugates of the release tag compounds and assay methods employing them are also disclosed.

Abstract: The disclosure relates to a method for resolving double-stranded DNA species differing by at least one base pair. Each of the species is characterized by an iso-melting domain with a unique melting temperature contiguous with a melting domain of higher thermal stability.

Abstract: A release tag reagent suitable for use in the chemical analysis of a substance to be detected comprises signal, release, and reactivity groups. A class of release tag compounds that are cleaved to release as signal groups very stable electrophoric ketones which are sufficiently volatile for determination in the gas phase of an analytical reaction mixture is disclosed.

Abstract: A release tag reagent suitable for use in the chemical analysis of a substance to be detected comprises signal, release, and reactivity groups. A class of release tag compounds that are cleaved to release as signal groups very stable electrophoric ketones which are sufficiently volatile for determination in the gas phase of an analytical reaction mixture is disclosed.

Abstract: A release tag reagent suitable for use in the chemical analysis of a substance to be detected comprises signal, release, and reactivity groups. A class of release tag compounds that are cleaved to release as signal groups very stable electrophoric ketones which are sufficiently volatile for determination in the gas phase of an analytical reaction mixture is disclosed.

Abstract: A release tag reagent suitable for use in the chemical analysis of a substance to be detected comprises signal, release, and reactivity groups. A class of release tag compounds that are cleaved to release as signal groups very stable electrophoric ketones which are sufficiently volatile for determination in the gas phase of an analytical reaction mixture is disclosed.

Abstract: Compounds and methods for single step, covalent labeling of the phosphate group of an organic substance under aqueous conditions are described. The labeling compound includes any kind of detectable signal group covalently bound to an imidazole moiety, which can be imidazole or a substituted imidazole.

Abstract: A general purpose technique called extractive hydrogenation analysis, useful for both trace component and imaging analysis of samples containing organic matter. In processes according to the invention, organic matter is thoroughly decomposed in the presence of a hydrogenation catalyst under substantially aqueous conditions into products, and one or more of the products is then detected.

Abstract: A heterobifunctional cross-linking reagent having a carbohydrate backbone (derived from a chitin substrate) is disclosed. The cross-linker is available in a variety of lengths, is highly water-soluble, and can be formulated to undergo cleavage catalyzed by the enzyme lysozyme.

Abstract: A release tag reagent suitable for use in the chemical analysis of a substance to be detected, which substance contains reactive groups, such as for, but not limited to gas phase detection groups, which reagent comprises three covalently bonded groups: a signal group which on release provides a ketone signal compound to be detected, a release group which may be cleaved to release the ketone signal group, which release group contains, for example, a vic glycol or an olefin group and a reactivity group which is reactive with a reactive group of the substance to be detected.

Abstract: A method for amplifying enzyme activity is disclosed. Enzyme amplification is achieved by covalently bonding enzyme to a supporting material via a molecular chain which is a substrate for the enzyme, then introducing a small amount of enzyme in the free state to this system, causing release of a large amount of bound enzyme. In an alternative embodiment, complementary enzymatically inactive fragments of an active enzyme, which fragments can recombine to form active enzyme, are covalently attached to separate support materials by a molecular chain material which is a substrate for the active enzyme, and these two fragment-supported conjugates are connected in series. Upon application of free enzyme or free complementary enzyme to one of these fragment-support conjugates, followed by application of the resulting product mixture to the second fragment-support conjugate, a large amount of free enzyme is ultimately produced.

Abstract: An improved, highly stable capillary column used in high performance capillary electrophoresis and method of preparing the same. The improved capillary column can significantly reduce the effects of electroosmosis during electrophoresis, is stable for reuse, and enables operation of the capillary column in high electric fields, resulting in high resolution separations in a minimum amount of time. The improved column comprises a capillary having a highly stable, coating matrix on the inner surface of the capillary wall. The highly stable coating matrix includes an intermediate layer hydrophobic phase chemically bonded to the inner wall of the capillary, a detergent which is physically adsorbed to the hydrophobic phase, and a polymerized monomer which is covalently bonded to the adsorbed detergent thereby forming a hydrophilic outer layer of the coating matrix.

Abstract: Enzyme amplification is achieved by covalently bonding enzyme to a supporting material via a molecular chain which is a substrate for the enzyme, then introducing a small amount of enzyme in the free state to this system, causing release of a large amount of bound enzyme. In an alternative embodiment, complementary enzymatically inactive fragments of an active enzyme, which fragments can recombine to form active enzyme, are covalently attached to separate support materials by a molecular chain material which is a substrate for the active enzyme, and these two fragment-support conjugates are connected in series. Upon application of free enzyme or free complementary enzyme to one of these fragment-support conjugates, followed by application of the resulting product mixture to the second fragment-support conjugate, a large amount of free enzyme is ultimately produced.

Abstract: A repetitive immunoassay analytical method for determination of a free analyte is carried out by loading an affinity column of covalently bound analyte with tagged antibody, passing a continuous aqueous stream of carrier liquid over the column, introducing an aliquot of a sample to be analyzed for free analyte into the carrier stream upstream of the column, and monitoring the eluting carrier stream for a signal spike resulting from the presence of tagged antibody material released from the column by the application of free analyte in the analytical sample. Many samples may be analyzed by this method before the antibody-loaded affinity column needs to be regenerated. It is also disclosed that substrate-analyte conjugates of superior stability are produced by linking a substrate to a hydroxyalkyl analyte via an amino, hydrazide, or sulfide linking group replacing a hydroxy group.

Abstract: A new class of chemical reagents called release tags which comprise signal, release and reactivity groups is disclosed and a release tag involving a pentafluorobenzoyl signal group, a methionylamide release group, and an active ester reactivity group is used to analyze the hormone, thyroxine, in serum, involving quantitation of the released signal group by gas chromatography with electron capture detection.

Abstract: Amidobiotin extender compounds useful, for example, in avidin-biotin multiple-layering process, which compounds include caproylamidobiotin-NHS ester, caproylamidobiotin-horse radish peroxidase, caproylamidobiotinribonuclease and caproylamidobiotin-alkaline phosphatase (B-ALP).

Abstract: A method of chemical analysis is disclosed which employs a release tag compound of general formulaRx--Re--Sin which Rx is a reactivity group capable of forming a covalent bond with another molecule, Re is a release group capable of being cleaved, and S is a signal group. The release tag is covalently bonded to a substance of interest which is to be determined in the course of a chemical analysis for an analyte, release group Re is cleaved at an appropriate point in the analytical procedure, and signal group S is determined, thereby determining the substance of interest. Where the substance of interest is the analyte, determination of S determines the analyte. Where the substance of interest is not the analyte but is related to the analyte concentration, determination of S allows indirect determination of analyte.

Abstract: A multiple-layer process for applying, in alternate, successive molecular layers, a protein material, and a ligand extender material to a surface to modify the properties of the surface and to the multiple-layer product so prepared.

Abstract: A multiple-layer process for applying, in alternate, successive layers, the protein, avidin, and a biotin-containing extender material to a solid surface to modify the properties of the surface and to the multiple-layer product so prepared.

Abstract: A multiple-layer process for applying, in alternate, successive layers, the protein, avidin, and a biotin-containing extender material to a solid surface to modify the properties of the surface and to the multiple-layer product so prepared.