Abstract: The present invention relates to methods for detecting the presence of ribonuclease enzymes, more specifically to methods that provide for a visual detection assay. The methods entail contacting a test sample suspected of containing ribonuclease activity with a substrate containing a ribonuclease-sensitive internucleotide linkage flanked directly or indirectly by a fluorescence reporter group and a dark quencher, such that if a ribonuclease activity is present in the sample, the ribonuclease-sensitive internucleotide linkage is cleaved and the fluorescence reporter group emits a visually detectable signal. The present invention further provides novel nucleic acid compositions used as substrates for such assays and encompasses kits for performing the methods of the invention.

Abstract: The present invention relates to methods for detecting the presence of ribonuclease enzymes, more specifically to methods that provide for a visual detection assay. The methods entail contacting a test sample suspected of containing ribonuclease activity with a substrate containing a ribonuclease-sensitive internucleotide linkage flanked directly or indirectly by a fluorescence reporter group and a dark quencher, such that if a ribonuclease activity is present in the sample, the ribonuclease-sensitive internucleotide linkage is cleaved and the fluorescence reporter group emits a visually detectable signal. The present invention further provides novel nucleic acid compositions used as substrates for such assays and encompasses kits for performing the methods of the invention.

Abstract: The invention relates to methods and systems for predicting or estimating the melting temperature of duplex nucleic acids, particularly duplexes of oligonucleotides which may be used, for example, as primers or probes in PCR and/or hybridization assays. The invention also relates to methods and systems for designing and selecting oligonucleotide probes and primers having a predicted melting temperature which is optimized for such assays. To this end, algorithms and methods are provided for predicting the melting temperature of a nucleic acid having a predetermined sequence. These methods and algorithms estimate the melting temperature of a nucleic acid duplex under particular salt conditions. The methods and algorithms use novel formulas, having terms and coefficients that are functions of the particular nucleotide sequence, to estimate the effect of particular salt conditions on the melting temperature.

Abstract: The invention provides novel anthraquinone compositions that are useful as broad-spectrum quenchers of fluorescence and provides methods for making and using them. The anthraquinone quenchers can be conjugated to a variety of biologically relevant compounds, including lipids, nucleic acids, polypeptides, and more specifically antigens, steroids, vitamins, drugs, haptens, metabolites, toxins, environmental pollutants, amino acids, peptides, proteins, nucleotides, oligonucleotides, polynucleotides, carbohydrates, and their analogs. The invention also provides kits comprising, in one or more containers, at least one anthraquinone quencher dye composition of the present invention, and instructions for using that composition.