17 results about "Intense fluorescence" patented technology

Provided are a pyrrolo[h]coumarin dye and a use thereof in sequencing. Specifically provided are a compound represented by formula I or a stereoisomer, tautomer, crystal form, salt, ester or solvate thereof. The compound has the advantages of high brightness and high stability. The compound exhibits strong fluorescence under blue light excitation. When used for labeling dNTPs and then applied in gene sequencing, the sequencing signal, resolution and throughput are all significantly improved, and the sequencing quality is significantly improved.

Methods and apparatuses dynamic range enhancement of fluorescence detectors are described herein. In one aspect, a method can include collecting, from a sample during a sample event, an emission spectrum that comprises a plurality of emission signals; based on reception times associated with emission signals of the plurality of emission signals, determining a lifetime estimation for the sample; determining, based at least on the lifetime estimation, a pileup factor affecting receiving emissions from the sample; and based on the determined pileup factor, adjusting a number of emission signals measured during the sample event to generate an estimated number of emissions for the sample event.

The present disclosure relates to a method of detecting binding of a labeled species to an analyte of interest. In some embodiments, the method comprises detecting binding of the labelled species to the analyte of interest within an area of electrical field enhancement, in the presence of a quencher.

This invention provides a device, system, and method for measuring OH radical concentration based on secondary excitation laser-induced fluorescence. The measuring device includes at least an optical path device and a gas path device. The gas path device includes at least a sampling nozzle and a fluorescence detection cavity. The sampling nozzle is disposed on the fluorescence detection cavity and is connected to the gas flow. The sampling nozzle collects atmospheric air to provide the OH radicals to be measured. The optical path device includes at least, sequentially, a laser generating component, an optical path adjustment component, a fluorescence detection cavity, and a reflection component along the laser emission direction. The optical path device also includes a photodetector disposed on the fluorescence detection cavity. The photodetector captures the fluorescence signal and converts it into an electrical signal. The technical solution of this invention uses a 308nm high-energy laser to secondary excite the OH radicals to be measured in the atmosphere to generate fluorescence. Under a specific low-pressure vacuum sealed environment, the fluorescence signal can be strengthened and the fluorescence lifetime extended, thereby making the detection results more accurate.

This invention discloses a reagent for detecting the content of aminoglycoside antibiotics and its application method. The reagent, by volume percentage, comprises 10-20% buffer solution, 8-12% anionic surfactant, 1-5% ANS-Na aqueous solution, and 60-65% ultrapure water. The detection method involves mixing the reagent with a water sample containing aminoglycoside antibiotics, reacting, and then performing fluorescence detection. The detection result is then used to calculate the content of aminoglycoside antibiotics using a standard curve. This invention utilizes the advantages of ANS-Na's high sensitivity, rapid response, and ease of operation. It forms a ternary nanoaggregate with the anionic surfactant and AGs, providing a hydrophobic environment for the small molecule fluorescent substance ANS-Na, thereby enhancing the fluorescence signal and achieving sensitive detection of AGs.

This invention discloses the selective detection of a fluorescent substrate and its application in detecting S-COMT activity, belonging to the field of analytical detection. The selective fluorescent substrate is 3-carboxy / methyldaphne (3A / M-DPN), which can be specifically catalyzed by S-COMT to generate an 8-O-methylated product, producing a strong fluorescence signal at 520 nm, and the fluorescence intensity shows a good linear relationship with S-COMT activity. The substrate of this invention has a high affinity for S-COMT (…). K m =1.41 μM) is much higher than that of membrane-bound MB-COMT ( K m =45.31 μM), catalytic efficiency ( V max / K m It is 280 times more potent than other substrates and possesses advantages such as high selectivity, high sensitivity, and ease of operation. This substrate can be used to distinguish the catalytic contribution of S-COMT from MB-COMT, quantitatively assess the S-COMT activity in various in vitro biological samples, and provide an important tool for S-COMT subtype functional studies, monitoring of S-COMT activity under pathological conditions, and screening of drugs targeting S-COMT.

A fluorescence intensity enhancer containing a water-soluble compound having a melting point of 50°C or higher, a fluorescence intensity enhancing method of a fluorescently labeled target biological substance using the fluorescence intensity enhancer, and a kit for fluorescence detection containing the fluorescence intensity enhancer.

The application provides a miRNA imaging application method based on an endogenous glutathione activated DNA sensor for logic cascade signal amplification. The technology constructs a "local catalytic hairpin assembly DNA nanomachine", and triggers a cascade reaction through endogenous glutathione (GSH) and target miRNA-21: GSH cleaves the disulfide bond on the GH1 hairpin, so that the conformation is changed into a metastable state H1, and then hybridizes with miRNA-21 to start branch migration, releases miRNA-21 to circulate and catalyze H2 hairpin assembly, and realizes exponential amplification of signals. FAM and BHQ1 on the H2 hairpin are spatially separated due to double-stranded formation, and the fluorescence resonance energy transfer is released, so that a strong fluorescence signal positively related to the concentration of miRNA-21 is generated. The method has high sensitivity (the detection limit is 3.92 pM), high specificity and excellent stability, is suitable for high-fidelity imaging detection of miRNA in living cells, and provides an efficient tool for cancer diagnosis and treatment integration.

The present application relates to an aptamer nucleic acid molecule, a complex containing the aptamer nucleic acid molecules, a method of detecting intracellular or extracellular RNA, DNA or other target molecules, and a kit containing the aptamer. The aptamer of the present application is capable of specifically binding a kind of fluorophore micromolecules, and can significantly enhance fluorescence intensity under excitation light of appropriate wavelength.

This invention discloses a dual-emission fluorescent nano-assembly, its preparation method, and its application in ATP detection. The co-assembly achieves the detection of adenosine triphosphate (ATP). This invention uses an amphiphilic TPE derivative as the energy donor and an amphiphilic imidazole compound as the anion acceptor to form a dual-emission fluorescent nano-assembly with sodium fluorescein. Significant energy transfer occurs, resulting in strong fluorescence from the sodium fluorescein. After sodium fluorescein is replaced by ATP, the donor regains strong fluorescence emission while the light from the sodium fluorescein is quenched, allowing for the fluorescence detection of ATP with a detection limit as low as 0.735 nM. This method is simple, sensitive, and enables rapid and accurate specific quantitative detection of ATP, and can be widely used in the biomedical field.

The invention provides an organic-inorganic hybrid one-dimensional tetranuclear zinc crystal material and a preparation method thereof, and belongs to the field of organic-inorganic hybrid materials and crystal materials. The chemical formula of the organic-inorganic hybrid one-dimensional tetranuclear zinc crystal material is [Zn (C12H8N2) (H2O)] 2 [Zn (C12H8N2) (C3H2O4) (H2O) 2] 2 (NO3) 4. 4H2O, the organic-inorganic hybrid one-dimensional tetranuclear zinc crystal material belongs to a triclinic system, and the space group is P1. A hydrothermal synthesis method comprises the following steps: adding phenanthroline dissolved in absolute ethyl alcohol into zinc nitrate, malonic acid and water, adjusting the pH value to a proper value by using a sodium hydroxide solution under a stirring state, and transferring the mixed solution into a closed system for hydrothermal reaction. The crystal material has strong fluorescence emission at the wavelength of 480 nm under the excitation of light with the wavelength of 320 nm, and can be used as a potential high-quality luminescent material.

The present disclosure provides a fluorescently-traceable amino acid derivative and a preparation method and use thereof, and belongs to the technical field of biomedicine. In the present disclosure, an amino acid skeleton of the amino acid derivative is modified mainly by a fluorescently-traceable functional group. 4-chloro-7-nitro-2,1,3-benzoxadiazole (NBD-Cl) has low polarity and strong fluorescence, and can be used to modify an N-terminal of the amino acid skeleton to conduct subcellular imaging. Moreover, the NBD-Cl has a relatively small volume, lacks reaction orthogonality, and causes little interference with biochemical reactions of the organism itself. The results of examples show that the fluorescently-traceable amino acid derivative has a desirable biological activity and can be fluorescently traced in vivo and in vitro.

The present application provides a kind of estrogen receptor positive breast cancer fluorescent probe by parent nucleus dye nile blue derivative, estrogen receptor (ER) recognition group tamoxifen and alkane chain three parts constitute, the probe has the structure of general formula 1.The probe shows folded conformation in water environment, there is photoinduced electron transfer effect between nile blue derivative and tamoxifen, no obvious fluorescence signal;When the probe recognizes ER protein, the recognition group is combined with the binding site, the conformation of the probe changes into unfolded conformation, and strong fluorescence signal is shown.The excitation wavelength of the probe is about 630 nm, the emission wavelength is about 640-700nm, has stronger tissue penetration ability, lower tissue self-absorption and light scattering, can be targeted to breast cancer cell overexpressed ER protein, and specifically highlights estrogen receptor positive breast cancer.

The application provides a dye for constructing a high-sensitivity long-wavelength fluorescent probe and a preparation method thereof, the fluorescent dye parent body is a rhodol dye, a structural formula of the rhodol dye is shown as formula A: formula A is connected with any one of the following structural formulas; wherein R1 is one of H, C1-20 alkyl and a benzene ring; R2 is one of H, F, Cl, Br and I; R3 is one of (n=0-20); R4 is one of (n=0-20). The rhodol dye covers a spectral range of 500-750 nm, is almost completely in an open ring state under physiological conditions, and is completely converted into a non-fluorescent spiro ring state by adopting a methyl or a response site shielding hydroxyl, therefore, the probe constructed based on the dye has extremely low self-background fluorescence; along with activation of the probe, the shielding hydroxyl is gradually released, the non-fluorescent probe is converted into a strong fluorescent dye, thereby the probe is endowed with a significantly improved response activation multiple and extremely high response sensitivity.

The present invention relates to a coumarin dye and the use thereof in sequencing. Specifically, provided is a compound as shown in formula I or a stereoisomer, tautomer, crystal form, salt, ester or solvate thereof. The compound has the advantages of high brightness and high stability, and exhibits strong fluorescence under blue-light excitation. When used for gene sequencing after labeling dNTPs, the compound significantly improves the sequencing signal, resolution and throughput, thereby significantly improving the sequencing quality.

The present application relates to the technical field of intelligent sensor, specifically to a Raman spectrum-based monk fruit agricultural residue fluorescence background suppression imaging method, which comprises the following steps: recognizing the gap between the hairy tissues of monk fruit by using a distance sensor, locking a three-dimensional pixel coordinate matrix and extracting local curvature feature mapping as a capillary pressure gradient field, guiding noble metal nano-probes to enrich at the root of the gradient field to construct a local enhanced hot spot, and outputting an enhanced signal stream; adopting frequency shift excitation combined with polarization differential phase detection, using polarization difference to strip scattering interference caused by the hairy tissues, and performing differential processing through image subtraction algorithm to obtain an agricultural residue differential image; and establishing an attenuation correction model based on surface topography and normal angle to perform pixel-level gain compensation on the signal and restore the real distribution concentration of agricultural residues. The present application is suitable for agricultural product detection scenes with complex hairy structure and strong fluorescence background, and can significantly improve the signal sensitivity, spatial imaging resolution and quantitative analysis capability of agricultural residue detection in a strong interference environment.