A thermosensitive fluorescent label for labeling of biological material with fluorescent dyes used for biological, chemical or physical analyzes. A method for fluorescence labeling of nucleosides, nucleotides and oligonucleotides with those fluorescent dyes wherein a moiety of general formula 1 or 2 or 3 or 4 with the double bond configuration is attached to a nucleoside, nucleotide or oligonucleotide.

The present disclosure embodies compounds of Formula I, methods of use thereof, and kits thereof: ##STR00001## that are useful in connection with the detection of analytes of all types (e.g., biological molecules such as proteins, organic molecules, natural or synthetic molecules). The disclosure is particularly applicable to detection of proteins and nucleic acids using all types of membrane-based assays by techniques such as Western blotting, Dot blotting, Southern blotting, and Northern blotting.

Voltage sensitive dyes comprising boron and related compositions and methods are provided. In some embodiments, a voltage sensitive dye comprises an electron acceptor comprising boron. The electron acceptor may be attached (e.g., covalently) to at least one electron donating group and at least one polar group. For instance, the electron acceptor may comprise optionally substituted boron dipyrromethene (e.g., optionally substituted 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene). The point of attachment and chemical nature of the electron donating group(s) and polar group(s) may be selected to impart beneficial properties to the voltage sensitive dye. For instance, the voltage sensitive dye may have an extended difference in the dipole moment between the ground and electronic states due at least in part to the position of the electron donating group(s). The voltage sensitive dyes, described herein, may have high specificity, high signal to noise ratio, fast responsivity, high voltage sensitivity, high photostability, and/or high brightness.

The invention provides fluorescent probes having the general formula (I)

##STR00001##

wherein X, Y, L and R.sup.1 to R.sup.4 are as described herein, compositions including the compounds, processes of manufacturing the compounds and methods of using the compounds.

A fluorescent dye, as well as a preparation method and uses thereof, wherein the fluorescent dye is sensitive and specific to viscosity and has low background fluorescence; it can also be used as a fluorescent activated and lighted probe used for fluorescent labeling, quantification or monitoring of protein, enzymes or nucleic acid.

Disclosed herein are compounds or salts and/or solvates of formula I, II and III, where the compounds or salts and/or solvates have the following structures: (X).sub.a—Y—(Z).sub.b I; II; or X′—Y′ III; where X, Y, Z, Y′, a, b, R.sub.4, R.sub.6 and R.sub.7 are as defined herein.

##STR00001##

A composition includes two or more near infrared absorbing compounds having an absorption maximum in a wavelength range of 650 to 1000 nm and having a solubility of 0.1 mass % or lower in water at 23° C., in which the two or more near infrared absorbing compounds include a first near infrared absorbing compound having an absorption maximum in a wavelength range of 650 to 1000 nm, and a second near infrared absorbing compound having an absorption maximum in a wavelength range of 650 to 1000 nm which is shorter than the absorption maximum of the first near infrared absorbing compound, and a difference between the absorption maximum of the first near infrared absorbing compound and the absorption maximum of the second near infrared absorbing compound is 1 to 150 nm.

Dye and compositions to monitor the multistep protein aggregation process in both test tubes and live cells are provided. These dyes can detect misfolded protein oligomers and distinguish insoluble protein aggregates from misfolded oligomers. Applications of these dyes include measuring kinetics of protein aggregation, monitoring aggregation of specific proteins in intact live cells, monitoring aggregation of cellular proteome in intact live cells, and tracking the time course of protein aggregation in cells under stress conditions.

According to the present teachings, compositions, kits, and methods for protein melt analysis are provided that utilizing one or more fluorophore dyes. In some embodiments, a method comprises preparing a sample by mixing at least one protein with two or more dyes, and applying a controlled heating, while recording the fluorescence emission of the sample. The methods can be used, for example, for screening conditions for optimized protein stability, screening for ligands that bind and enhance protein stability (e.g., protein-protein interactions), screening for mutations for enhanced stability, screening crystallization conditions for protein stability, screening storage conditions for protein stability, and screening conditions in which a protein will be used (e.g., production conditions, treatment conditions, etc.) for protein stability.

The merocyanine compound of the present invention causes a spectral change of a hypochromic shift in the vicinity of the wavelength of 512 nm by intercalation between dsRNA nucleotide pairs, and the spectral change shows high accuracy and reproducibility, so the merocyanine compound of the present invention can be effectively used for detecting dsRNA and comparing the expression levels between samples. In addition, the present invention relates to a method for providing information for the diagnosis of cancer comprising the steps of 1) measuring the expression level of dsRNA in a sample of a test subject; and 2) comparing the expression level of dsRNA measured in step 1) with that of the normal control group, and a composition for detecting dsRNA comprising a merocyanine compound, a salt thereof or an isomer thereof. The present invention can provide information for the diagnosis of cancer by measuring the expression level of dsRNA separated from a sample of a test subject and comparing it with that of the normal control group. Further, the responsiveness of a patient to the treated drug can be predicted by treating the sample with a drug and measuring the expression level of dsRNA.