Abstract: The present invention relates to a method for detecting the amount of a target polynucleotide in a sample. A combination is provided in a medium. The combination comprises (i) a sample suspected of containing the target polynucleotide, the target polynucleotide being in single stranded form, (ii) a reference polynucleotide comprising a sequence that is common with a sequence of the target polynucleotide, and (iii) a predetermined amount of an oligonucleotide probe that has a sequence that hybridizes with the sequence that is common. The combination is subjected to conditions for amplifying the target polynucleotide and the reference polynucleotide. The conditions permit formation of substantially non-dissociative complexes of the target polynucleotide and the reference polynucleotide, respectively, with the oligonucleotide probe. Furthermore, the predetermined amount of the oligonucleotide probe is less than the expected amount of the amplified target polynucleotide.

Abstract: A method is disclosed for detecting the presence of a difference between two related nucleic acid sequences. In the method a complex is formed comprising both strands of each sequence. Each member of at least one pair of non-complementary strands within the complex have labels. The association of the labels as part of the complex is determined as an indication of the presence of a difference between the two related sequences. The complex generally comprises a Holliday junction. In one aspect a medium suspected of containing said two related nucleic acid sequences is treated to provide partial duplexes having non-complementary tailed portions at one end. The double stranded portions of the partial duplexes are identical except for said difference.

Abstract: Compounds that are modified polysaccharides having pendant aldehyde functionalities are disclosed. Each of the aldehyde functionalities is attached through a linker to a position corresponding to a hydrogen atom of a different hydroxyl group of unmodified polysaccharide. Also disclosed is a method for introducing an amine-reactive functionality into a dextran. The method comprises (a) reacting the dextran with an alkylating agent having a functionality that reacts with an hydroxyl group of the dextran thereby forming an alkylated dextran wherein the alkylating agent has an olefin group and (b) treating the alkylated dextran to convert the olefin group to an amine-reactive functionality. A polysaccharide can be conjugated to a biomolecule by carrying out the above method and reacting the amine-reactive functionality with an amine functionality on the biomolecule to produce polysaccharide conjugated to the biomolecule.

Abstract: The present invention relates to methods for immunoassay of analytes employing mutant glucose-6-phosphate dehydrogenase (G6PDH) enzymes as labels. In particular, the invention relates-to the use of conjugates of an analyte or analyte analog and a mutant NAD+ dependent G6PDH differing from any precursor G6PDH by the deletion, substitution, or insertion, or any combination thereof of at least one amino acid per subunit. The invention also involves the construction of several mutations in precursor glucose-6-phosphate dehydrogenase (G6PDH) enzymes. Typically, the mutations involve deletion or substitution of one or more lysine residues, or introduction of one or more cysteine residues by insertion of cysteine to precursor G6PDH or substitution of precursor G6PDH amino acids residues with cysteine.

Abstract: A method of measuring the amount of cyclosporin in a sample suspected of containing cyclosporin is disclosed. A method of inactivating interfering cross-reactive material in an assay for measuring the amount of cyclosporin in a sample suspected of containing cyclosporin is also disclosed. Compositions wherein cyclosporin is conjugated to an immunogenic carrier or a label, optionally through a linking group, at an alanine nitrogen atom of the cyclic backbone of cyclosporin are also disclosed. Compositions wherein atiocyclosporin is conjugated, optionally through a linking group, to an immunogenic carrier or a label are also disclosed. Where cyclosporin is conjugated to an immunogenic carrier, the conjugates may be used as immunogens for the preparation of antibodies which are capable of recognizing cyclosporin.

Abstract: The present invention relates to a method for selectively extending an oligonucleotide primer along a specific target polynucleotide sequence in a mixture of polynucleotides. A combination is provided comprising the mixture, an oligonucleotide primer having a modification, and a binding substance for the modification wherein the binding substance binds to the oligonucleotide and prevents the extension of the oligonucleotide along the target polynucleotide sequence. The temperature of the combination is adjusted to a level sufficient to irreversibly denature the binding substance and permit the extension of the oligonucleotide primer along the specific target polynucleotide sequence. The invention has particular application in the amplification of nucleic acids. Also disclosed are kits for carrying out a method in accordance with the present invention.

Abstract: The present invention relates to compounds that are bis-biotins. These compounds comprise two biotinyl radicals connected by a chain of atoms, usually at least 16 atoms in length. The bis-biotin is conjugated to a member of a specific binding pair ("sbp member") wherein the chain is not part of the sbp member. Also disclosed are compositions comprising a complex of avidin and a bis-biotin as described above. The compounds and compositions of the invention find use in an assay for an analyte wherein there is employed a reagent system comprising an avidin reagent and a biotin reagent. The improvement of the present invention comprises using as the biotin reagent a bis-biotin as described above. Also disclosed are kits comprising the present bis-biotins and methods of preparing a bis-biotinylated conjugate of a member of a specific binding pair ("sbp member") for use in a specific binding assay.