摘要:
A method is disclosed for extending an extender probe to produce a single stranded polydeoxynucleotide that is free of unreacted extender probe and has two segments that are non-contiguous and complementary with each other. The method comprises the steps of (1) providing in combination (a) a polynucleotide having two non-contiguous, non-complementary nucleotide sequences S1 and S2 wherein S2 is 5' of S1 and is at least ten deoxynucleotides long, (b) an extender probe comprised of two deoxynucleotide sequences, wherein the sequence at the 3'-end of the extender probe (EP1) is hybridizable with S1 and the other of the deoxynucleotide sequences (EP2) is substantially identical to S2 and (c) means for modifying the 3'-end of extender probe that does not hybridize with the polynucleotide and (2) extending the extender probe along the polynucleotide wherein extender probe not hybridized to the polynucleotide becomes modified at its 3'-end.
摘要:
A method is disclosed for determining the presence of a polynucleotide analyte in a sample suspected of containing the analyte. The method comprises (a) forming as a result of the presence of an analyte a single stranded polynucleotide comprising a target polynucleotide binding sequence flanked by first and second polynucleotide sequences that differ from the sequence of the analyte or a sequence complementary to the analyte sequence, (b) forming multiple copies of the single stranded polynucleotide, and (c) detecting the single stranded polynucleotide. Also disclosed is a method of producing at least one copy of a single stranded polynucleotide. The method comprises (a) forming in the presence of nucleoside triphosphates and template dependent polynucleotide polymerase an extension of a polynucleotide primer at least the 3'-end of which has at least a 10 base sequence hybridizable with a second sequence flanking the 3'-end of the single stranded polynucleotide, the second sequence being partially or fully complementary with at least a 10 base first sequence flanking the 5' end of the single stranded polynucleotide, (b) dissociating the extended polynucleotide primer and the single stranded polynucleotide, (c) repeating step a and (d) dissociating the extended polynucleotide primer and the copy of the single stranded polynucleotide.
摘要:
Methods and kits are disclosed for preventing amplification of contaminating copies of nucleic acids during in amplification of a nucleic acid suspected of being present in a sample. Modified nucleotides that render copies of the nucleic acid bindable by a member of a specific binding pair, such as a receptor, which does not bind to the nucleic acid, are incorporated into copies of the nucleic acid that are produced during the amplification. The sample is combined with an enzyme conjugate, usually a receptor bound to a nuclease, under conditions wherein prior to the amplification the member of a specific binding pair binds to the copies and the enzyme degrades the copies but not the nucleic acid. The methods and kits have particular application to the determination of a nucleic acid analyte.
摘要:
The present invention relates to a method for detecting or amplifying and detecting a target polynucleotide sequence. The method comprises providing in combination (i) a medium suspected of containing the target polynucleotide sequence, (ii) all reagents required for conducting an amplification of the target polynucleotide sequence when amplification is desired, and (iii) two oligonucleotide probes capable of binding to a single strand of the product of the amplification. At least one of the probes has two sequences that either (i) are non-contiguous and bind to contiguous or non-contiguous sites on the single strand or (ii) can bind to non-contiguous sites on the single strand. Each probe may contain a label. The combination is subjected to conditions for amplifying the target polynucleotide sequence. Next, the combination is subjected to conditions under which both of the probes hybridize to one of the strands to form a termolecular complex, which is detected by means of the label.
摘要:
A method is disclosed for producing at least one copy of a pair of complementary single stranded polynucleotides. The method comprises forming, in the presence of nucleoside triphosphates and template dependent polynucleotide polymerase along each of the complementary single stranded polynucleotides, an extension of a polynucleotide primer. The polynucleotide primer is comprised of at least a sequence of 16 nucleotides terminating at its 3′ end in a 2 to 9 nucleotide sequence (S1), which is complementary with the 3′ ends of both of the complementary single stranded polynucleotides. The polynucleotide primer has at least an 8 nucleotide sequence (S2) that is 5′ of S1, where S2 is 50 to 80% complementary to the nucleotide sequences contiguous with the 3′ ends of the complementary single stranded polynucleotides. The extended polynucleotide primer and the single stranded polynucleotides are then dissociated.
摘要:
Methods are disclosed for determining minute quantities of an analyte in a medium suspected of containing the analyte. One method comprises treating a medium suspected of containing an analyte under conditions such that the analyte, if present, causes a substrate having an oxidant cleavable linker and a photosensitizer to come into close proximity. The photosensitizer generates singlet oxygen which oxidatively cleaves the linker to form a product which can be detected in a sandwich detection assay such as LOCI. The amount of product detected is related to the amount of analyte in the medium. Compositions, kits, and compounds are also disclosed.
摘要:
Methods, compositions and kits are disclosed. The compositions are light emitting and comprise a polymeric matrix having dissolved therein a photoactive compound. The composition has the characteristic that, after activation of the photoactive compound, the rate of decrease in the intensity of light emission at any time during a 20-fold decrease in the intensity is proportional to the intensity of the light emission. In one embodiment the polymeric matrix is comprised of particles of about 20 nm to about 100 μm in diameter to which is bound a specific binding pair member. The particles generally comprise a polymeric matrix having dissolved therein about 1 to about 20% by weight of a dopant. The compositions may be used in methods for determining an analyte. A combination is provided comprising (1) a medium suspected of containing the analyte, (2) and the aforementioned composition. The photoactive substance is activated and the effect of the activating on the optical properties of the combination is detected. The presence and amount of the effect is related to the presence and amount of the analyte in the medium. Also disclosed are kits for use in an assay.
摘要:
Alpha-haloketones are useful alkylating agents for coupling to sulfhydryl-containing biomolecules. However, they react spontaneously with water, alkali and organic bases and therefore cannot be stored for extended periods of time in aqueous solutions, particularly in the presence of proteins at physiological pH. The present invention provides novel solutions to these problems, however, as novel compounds and compositions comprising protected haloketones are disclosed herein. Methods of preparing and using protected haloketones which are useful in a variety of applications—e.g., in assays and conjugation reactions—are also disclosed herein.
摘要:
Devices and methods are provided using microfluidic devices for manipulating small volumes and determining a variety of chemical and physical events. The devices rely upon an opening to the atmosphere of a small volume in a zone, where a sample is placed in the zone where evaporation can occur. The zone is maintained in contact with a liquid medium that serves to replenish the liquid in the zone and maintain the composition of the mixture in the zone substantially constant. The diffusion of components in the zone is restricted during the course of the determination by the liquid flux into the zone.
摘要:
Devices and methods are provided using microfluidic devices for manipulating small volumes and determining a variety of chemical and physical events. The devices rely upon an opening to the atmosphere of a small volume in a zone, where a sample is placed in the zone where evaporation can occur. The zone is maintained in contact with a liquid medium that serves to replenish the liquid in the zone and maintain the composition of the mixture in the zone substantially constant. The diffusion of components in the zone is restricted during the course of the determination by the liquid flux into the zone.