26 results about "Ratiometric fluorescence" patented technology

The application discloses an aggregation-induced emission compound with double fluorescence emission characteristics and a preparation method and application thereof, and the proportional fluorescence probe has a structure of general formula I. The probe molecule has a polar response group tetraphenyl ethylene as a fluorescence report unit, introduces a hydrophilic oxygen atom, connects an alpha carbon of an acetamide, and connects a polar detection sensitization group Tag chain on an amino group of the acetamide. The probe molecule improves the conjugation degree of oxygen atom lone pair electrons and a tetraphenyl ethylene pi electron system, so that the probe molecule simultaneously produces n→pi* and pi→pi* molecular transitions, and a proportional fluorescence probe which can sensitively respond to polarity change is constructed. The fluorescence probe designed in the application has the advantages that the fluorescence probe is not easily interfered by probe concentration, a detection environment and light bleaching, and experiments prove that the proportional fluorescence intensity of the fluorescence probe can sensitively respond to polarity, and the proportional fluorescence intensity and water content are linearly fitted, so that the purposes of detecting water content in an organic reagent and alcohol content in wine are achieved.

The invention discloses a preparation method of a portable paper-based ratiometric fluorescence sensor APBA-CsPbBr3 at-UiO-66 / Ru, which comprises the following steps: 1, adding lead bromide and cesium bromide into N, N-dimethylformamide, then adding 5-bromovaleric acid and an oleylamine ligand, and stirring; 2, perfluorooctyltriethoxysilane is added, and a precursor solution is obtained; 3, adding zirconium chloride and terephthalic acid into N, N-dimethylformamide to obtain a homogeneous solution; 4, after heating, UiO-66 is obtained; 5, stirring the precursor solution, APBA, UiO-66 and tris (2, 2-dipyridyl) ruthenium chloride hexahydrate to obtain a composite material; and 6, dropwise adding the composite material solution into the filter paper. The APBA modified material is adopted as a recognition unit, the APBA modified material and the paper base construct a fluorescence sensing platform, visual quantitative analysis of oxytetracycline in water is achieved, and the device is convenient to carry, low in detection limit, high in anti-interference performance, easy and convenient to operate and suitable for on-site rapid detection of oxytetracycline.

This invention discloses a dual-emission molecularly imprinted ratiometric fluorescence sensor, its preparation method, and its application in the detection of chlortetracycline, belonging to the field of chemical sensor technology. The preparation method of this sensor includes the following steps: preparing silica-quantum dot composite nanoparticles; preparing a molecularly imprinted polymer using salicylamide as a template molecule; and using a post-mixing strategy to mix the molecularly imprinted polymer and silica-quantum dot composite nanoparticles in HEPES buffer to construct the dual-emission molecularly imprinted ratiometric fluorescence sensor. The advantages of this invention are: the dual-emission molecularly imprinted ratiometric fluorescence sensor provided by this invention exhibits rich fluorescence color changes, enabling rapid, highly sensitive, and visual detection of chlortetracycline; and the entire detection process is simple, convenient, and fast, making it suitable for widespread application in practical applications.

This invention discloses a GSH-functionalized carbon dots / rhodamine B ratiometric fluorescence system, its construction method, and its application in nitrite detection. GSH-CDs are synthesized via a one-step hydrothermal method by mixing citric acid, o-phenylenediamine, glutathione, and hydrochloric acid in water. Unreacted precursors and small molecules are removed by purification, and the GSH-CDs are obtained by freeze-drying. The ratiometric fluorescence system is constructed by mixing rhodamine B, GSH-CDs, and an acidic buffer solution. The fluorescence intensity ratio F of GSH-CDs to rhodamine B is established. 460 / F 590 With nitrite (NO2) ‑ A calibration curve between concentrations was obtained, and the NO2 in the actual sample was experimentally detected using the spiked recovery method. ‑ Content. Under acidic conditions, with NO2... ‑ With increasing concentration, the GSH-CDs / RhB fluorescence intensity ratio (I 460 / I 590 Significant changes occurred, with the fluorescence intensity ratio compared to NO2. ‑ There is a good linear relationship between concentrations. Compared with the detection platform based on GSH-CDs, the ratio fluorescence system provided by this invention has a lower detection limit and significantly higher sensitivity.

This invention belongs to the field of food and agricultural product safety testing technology, specifically relating to a rapid detection method for parathion and its application. Based on the parathion-induced blue shift in fluorescence of silicon nanoparticles, ascorbic acid is reacted with 3-aminopropyltriethoxysilane to generate green fluorescent silicon nanoparticles. During the formation of silicon nanoparticles, parathion can embed itself into the porous structure of the silicon nanoparticles through host-guest interactions, causing a change in the excited state of the silicon nanoparticles. This affects the fluorescence emission of the silicon nanoparticles, resulting in a blue shift in the fluorescence emission peak, changing from green fluorescence to blue fluorescence, specifically manifested as an increase in fluorescence intensity at 422 nm and a decrease in fluorescence intensity at 520 nm. By establishing the relationship between ratiometric fluorescence signal or fluorescence color change and parathion concentration, specific detection of parathion is achieved. This invention requires no enzymes or antibodies for parathion detection, is inexpensive, fast, easy to operate, highly sensitive, and has good specificity.

This invention provides a method for constructing a donor-acceptor type perylene diimide-based porous conjugated polymer probe and detecting methamphetamine and amphetamine solutions. The method synthesizes donor-acceptor type perylene diimide-based porous conjugated polymer probes with different topologies by combining an electron acceptor perylene diimide derivative and an electron donor aggregation-induced emission fluorophore via a succinate coupling reaction. When used for the detection of methamphetamine and amphetamine, this system exhibits a clear ratiometric fluorescence response, with the fluorescence color gradually changing from yellow-green to orange and orange-red, demonstrating a significant ratiometric fluorescence response. It features fast response speed, high detection sensitivity, good selectivity, and no interference from other common structurally and property-similar substances, enabling the differentiation and identification of methamphetamine and amphetamine.

This invention discloses the construction and application of a multifunctional ratiometric fluorescence sensing platform based on aggregation-induced emission nanozymes, belonging to the field of nanocomposite materials technology. This invention involves the stepwise synthesis of a zirconium-based aggregation-induced emission metal-organic framework (Zr-TCPE) and cadmium telluride quantum dots (CdTe QDs), followed by the preparation of a Zr-TCPE / CdTe ratiometric fluorescent nanozyme using an electrostatic self-assembly method. In this composite material, Zr-TCPE exhibits organophosphorus hydrolase-like activity, specifically catalyzing the hydrolysis of para-oxygen and phosphorus, resulting in specific quenching of its fluorescence at 475 nm. Meanwhile, the fluorescence of CdTe QDs remains stable at 585 nm, enabling self-calibrated detection through the ratio of the two fluorescence signals. This invention features mild synthesis conditions and simple operation. The constructed sensing platform has a detection range spanning four orders of magnitude, a low detection limit, strong anti-interference ability, and excellent long-term stability over 24 days. It can be effectively used for rapid and highly sensitive detection of para-oxygen and phosphorus in complex samples of organophosphorus pesticides.

This invention proposes a ratiometric fluorescent probe molecule for detecting peroxynitrite, its preparation method, and its application, aiming to solve a problem in the technical field of fluorescent sensing materials. The ratiometric fluorescent probe molecules of this invention are HPIP-T-BnB and HPIP-K-BnB. The structural formulas of HPIP-T-BnB and HPIP-K-BnB are: [Insert structural formula here], and the structural formulas of HPIP-K-BnB are: [Insert structural formula here]. The preparation method includes the following steps: 4'-(diphenylamino)-4-(imidazo[1,2-a]pyridin-2-yl)-[1,1'-biphenyl]-3-ol or 4'-(9H-carbazole-9-yl)-4-(imidazo[1,2-a]pyridin-2-yl)-[1,1'-biphenyl]-3-ol undergoes a nucleophilic substitution reaction with 2-(4-(bromomethyl)phenyl)-4,4,5,5-tetramethyl-1,3,2-dioxoborhecyclopentane to obtain HPIP-T-BnB and HPIP-K-BnB. The probes prepared in this invention can detect ONOO⁻ with high selectivity, high sensitivity, and quantification, and have been successfully applied to ratiometric fluorescence imaging of exogenous and endogenous ONOO⁻ in live cells. This provides a reliable and crucial tool for mechanism research and drug development in related diseases.

The invention discloses a method for detecting total phosphorus concentration in an anaerobic fermentation system by using a ratiometric fluorescence sensor, the method is characterized in that the ratiometric fluorescence sensor is used for detecting total phosphorus in the anaerobic fermentation system, the adopted ratiometric fluorescence sensor is a lanthanide series metal organic framework suspension, and the lanthanide series metal organic framework is formed by europium ions and [1, 1 ': 4', 4 ', 4', 4 ', 4', 4 ', 4', 4 ', 4', 4 ', 4', 4 ', 4', 4 ', 4', 4 ', 4 The compound is composed of 1, 1 ', 1'] terphenyl-3, 3 ', 5, 5'-tetracarboxylic acid. According to the method disclosed by the invention, the ratio fluorescence sensor has the advantages of high energy transfer efficiency, good fluorescence performance and the like, can realize rapid and accurate detection when being used for detecting the total phosphorus concentration in the anaerobic fermentation system, and has the advantages of short detection time, high detection sensitivity, large detection linear range, high detection precision, strong anti-interference capability and the like; the total phosphorus concentration of different stages in the anaerobic fermentation system can be timely and accurately obtained, so that effective data can be provided for accurate analysis and effective control of the anaerobic fermentation system.

The invention discloses a ratio type fluorescent probe and application thereof in distinguishing and detecting aflatoxin B1 and aflatoxin B2a, and belongs to the field of fluorescent probe detection. The probe is assembled by taking serum albumin (HSA) as a subject and dicyanoisophorone dye (MDM) as an object. Based on the combination principle difference that an MDM derivative and aflatoxin B1 tend to coexist in HSA and the MDM derivative and aflatoxin B2a tend to be replaced, the ratio-type fluorescent probe MDM-coated HSA disclosed by the invention can realize distinguished detection of B1 and B2a by utilizing spectral response sensitivity difference and fluorescence color signals. The probe can be used for quantitatively detecting aflatoxin B2a in a real food sample due to high sensitivity of B2a, a colorimetric signal generated by ratiometric fluorescence of the probe can be used for on-site qualitative rapid detection, and dual-wavelength response can be used for in-situ differentiated imaging of B1 and B2a in a biological system.

The invention discloses a method for specific detection of sodium dichloroisocyanurate in ratiometric fluorescence-colorimetric dual modes, and belongs to the technical field of ratiometric fluorescence-colorimetric dual-mode sensors and sodium dichloroisocyanurate detection. The invention specifically constructs a sensor for specific detection of sodium dichloroisocyanurate in a ratio fluorescence-colorimetric dual mode, designs a method for specific and high-sensitivity detection of sodium dichloroisocyanurate in combination with ratio fluorescence and colorimetric, and can construct linear detection models at 4.0-40.0 [mu] mol / L and 2.0-70.0 [mu] mol / L respectively. And a novel and feasible method is provided for detection of sodium dichloroisocyanurate.

A method for dual-mode detection of beta-lactam antibiotic residues based on laccase-like activity nano-enzyme Cu-MOF is characterized in that a copper metal organic framework (Cu-MOF) with laccase-like activity and blue fluorescence is prepared by adopting a hydrothermal method, color change is generated in the process of oxidizing o-phenylenediamine (OPD) to generate a yellow product 2, 3-diaminophenazine (DAP), and the color change is changed in the process of oxidizing o-phenylenediamine (OPD) to generate the yellow product 2, 3-diaminophenazine (DAP). And dual-mode signal output of colorimetric and ratiometric fluorescence is realized. When the BLs exist, the BLs and OPD are competitively combined with Cu-MOF active sites, generation of DAP is inhibited, a colorimetric signal is weakened, blue fluorescence is recovered, and therefore high-sensitivity and high-selectivity detection of the BLs is achieved. According to the invention, a portable on-site quantitative detection platform is established by further combining smartphone image acquisition and RGB analysis technologies, is successfully applied to rapid and accurate detection of BLs residues in animal-derived foods such as milk and pork, and has the advantages of simplicity and convenience in operation, low cost, on-site applicability and the like.

A method for ratiometric detection of putrescine using PtPd NPs@TPE fluorescent nanozymes. This invention first utilizes mesoporous platinum-palladium nanoparticles (PtPd NPs) doped with tetraphenylethylene (TPE) to obtain fluorescent nanoparticles (PtPd NPs@TPE) with oxidase-like activity, which can produce blue fluorescence under 365 nm ultraviolet light excitation. Secondly, this invention utilizes the antioxidant properties of putrescine solution to inhibit the formation of 2,3-diaminophenazine (DAP), an oxidation product, during the oxidation of o-phenylenediamine (OPD) by PtPd NPs@TPE, thereby reducing the DAP content. Based on the relationship between putrescine concentration and the colorimetric intensity of DAP, and the ratio of the yellow fluorescence intensity of DAP at 552 nm to the blue fluorescence intensity of PtPd NPs@TPE at 442 nm, a novel ratiometric fluorescence method for detecting putrescine is constructed. This method can be used to detect actual samples such as dried bean curd, with a detection limit as low as 0.0025 μg / mL.

The invention discloses a multifunctional nano material fluorescence-colorimetric dual-mode food-borne pathogenic bacterium detection and killing method and a system thereof. According to the method, a metal organic framework material (MIL-53 (Fe)) with nano-enzyme activity is used as a signal switch and a generator, carbon nanodots (CDs) of a fluorescence indication and photo-thermal sterilization unit are combined to form a basic platform, and masking of an aptamer on a nano-enzyme active site and competitive release under triggering of target bacteria are used as a core mechanism. A colorimetric and ratiometric fluorescence double-signal channel is activated to realize self-verification high-precision detection; cDs in the system are used as a photo-thermal element, and in-situ photo-thermal sterilization is realized after detection. The platform design that detection objects can be switched by replacing the aptamers shows good universality and application prospects, and a sensitive and efficient new strategy is provided for detection and elimination of food-borne pathogenic bacteria.

The invention relates to the technical field of biological monitoring, in particular to a fluorescence sensor for detecting endocrine disruption activity in sewage and application. A Y-type polypeptide containing an anchoring region, a hinge region and an antifouling region is creatively designed as a structural skeleton, and the tail ends of a main chain and a branch chain are respectively subjected to directional modification to prepare the multifunctional ligand-polypeptide-dye conjugate; an optical biosensing chip, namely a ligand-polypeptide-dye conjugate functionalized biosensing chip which is high in reaction efficiency, strong in anti-pollution characteristic and capable of being stably regenerated, is constructed by adopting a covalent coupling method, and then the quantum dot-nuclear receptor fluorescent probe which is high in sensitivity and adjustable in emission spectrum is prepared. The ratio fluorescence biosensing principle based on fluorescence resonance energy transfer is provided, rapid quantitative detection of the endocrine disruptors in sewage is achieved, and the endocrine disruptors have broad-spectrum specific recognition capacity on a certain type of endocrine disruptors.

This invention discloses an acridine-based fluorescent nanofilm, its preparation method, and its application in the fluorescence sensing detection of ethylenediamine, belonging to the field of gas phase sensing materials. The fluorescent nanofilm is prepared by the self-assembly reaction of an aldehyde-modified acridine derivative and calix[4]pyrroletetrahydrazine at the gas-liquid interface via acylhydrazone bonds. By controlling the precursor concentration and reaction time, this invention can achieve precise control of the nanofilm thickness. The prepared nanofilm has excellent self-supporting properties and a uniform porous network structure, effectively suppressing the aggregation-induced quenching effect. When this nanofilm is used as a fluorescent sensing material for the detection of ethylenediamine, it exhibits a ratiometric fluorescence response, with advantages such as fast response speed, rapid recovery, low detection limit, high selectivity, and good stability, which can meet the needs of rapid on-site visualization detection. The preparation method of this invention is simple, the reaction conditions are mild, and no template is required, which has important application prospects in the field of on-site visualization detection of ethylenediamine.

The invention relates to the technical field of fluorescence sensing detection, in particular to a molecularly imprinted ratiometric fluorescence sensor which comprises a response signal assembly and a reference signal assembly, the response signal assembly is molecularly imprinted polymers (MIPs) loaded with 7-hydroxycoumarin, and the reference signal assembly is CdTe-coated SiO2 quantum dots; the molecularly imprinted polymer is prepared by taking isopropyl methanesulfonate as a template molecule, ethylene glycol dimethacrylate (EDGMA) as a cross-linking agent and azodiisobutyronitrile (AIBN) as an initiator through a precipitation polymerization method. The defect that a single-emission fluorescence sensor is easily influenced by background noise, instrument fluctuation and environmental factors is effectively avoided, and the detection accuracy and reliability are improved.

This invention proposes a quantum dot@ZIF-8 composite material, its preparation method, and its applications, belonging to the field of functional nanomaterials and fluorescence sensing analysis and detection technology. This invention involves mixing CdTe quantum dots (CdTe QDs) with red fluorescence emission and carbon quantum dots (C QDs) with blue fluorescence emission in a specific ratio, followed by in-situ self-assembly growth of ZIF-8, resulting in a quantum dot@ZIF-8 composite material with dual fluorescence signal emission. The quantum dot@ZIF-8 nanocomposite material prepared by this method not only possesses the fluorescence properties of quantum dots but also largely retains the original structure and properties of ZIF-8, making it a simple and effective method for preparing composite materials with excellent fluorescence performance. This quantum dot@ZIF-8 composite material can be used to prepare ratiometric fluorescence sensing probes for the visual detection of glucose with high sensitivity.

The invention discloses a CuIP2S type complex luminescent material and sensing application of a sensing film or sheet prepared from the CuIP2S type complex luminescent material or a sensing device prepared by compounding the CuIP2S type complex luminescent material with a europium complex internal standard to pyridine VOC (Volatile Organic Compounds). The structural formula of the luminescent material is CuI (TPP) 2 (DMMP), in the formula, TPP is electrically neutral monophosphine ligand triphenylphosphine, and DMMP is sulfur-containing ligand 4, 6-dimethyl-2-mercaptopyrimidine; the material is relatively weak in luminescence, so that after the material is placed in a pyridine or p-methylpyridine atmosphere, fluorescence-enhanced sensing response is quickly presented; the material can be easily prepared into a paper-based or polymer-doped sensing film or sheet, and the paper-based or polymer-doped sensing film or sheet also rapidly shows fluorescence enhancement response in an atmosphere; the material can be easily prepared into an internal standard composite sensing device, and rapidly shows a ratio type fluorescence response effect in an atmosphere; the devices show fluorescent sensing performance of reversible rapid selective response and sensitive recognition, and can be used as portable fluorescent sensing test paper devices to be applied to detection of pyridine VOCs (Volatile Organic Compounds).

This invention relates to a ratiometric sensor based on UiO-66-NH2@TT-COF composite material and its preparation method. The ratiometric sensor based on UiO-66-NH2@TpTt-COF composite material is synthesized by using an interface growth method to coat a TpTt-COF shell onto the surface of UiO-66-NH2, resulting in a UiO-66-NH2@TpTt-COF composite material with dual emission properties. A ratiometric fluorescence sensor can then be constructed using this UiO-66-NH2@TpTt-COF composite material. This invention uses an interface growth method to coat a TpTt-COF shell onto the surface of UiO-66-NH2, thereby synthesizing a UiO-66-NH2@TpTt-COF composite material with dual emission properties, thus constructing a novel ratiometric fluorescence sensor. When used to detect tetracycline, it achieves high selectivity and high sensitivity, thus providing a novel synchronous response sensor for antibiotic detection and offering a new possibility for the use of core-shell MOF@COF composite materials in the field of food safety.

This invention discloses a mixed broad-spectrum nucleic acid aptamer for the simultaneous detection of nine sulfonamide drugs and its applications. The mixed broad-spectrum nucleic acid aptamer is composed of nucleic acid aptamer sequences Sul-01 and Sul-04, which can be used as probes to construct a ratiometric fluorescence method for the simultaneous detection of nine sulfonamide drugs. The mixed broad-spectrum nucleic acid aptamer provided by this invention exhibits high specificity and high binding affinity for multiple sulfonamide drugs. The detection method established using it can achieve rapid, low-cost, and highly sensitive simultaneous detection of nine sulfonamide drug residues in aquatic environments and seafood.

The invention provides an allergen detection sensor, a preparation method thereof and a rapid detection device, the sensor comprises a response signal material, the response signal material is a carbon quantum dot material prepared based on plant cocklebur fruit, and the carbon quantum dot material has specific recognition capability on a target allergen; the reference signal material is combined with the carbon quantum dot material to form a proportional fluorescent probe; and the carrier is loaded with a proportional fluorescent probe. The sensor provided by the invention has the characteristics of simple preparation, low cost, rapid reaction and high specificity, and can be used for rapid detection of allergens.

This invention discloses a ZnMOF-based ratiometric fluorescence sensor, its preparation method, and its application, belonging to the field of analytical detection technology. The ZnMOF-based ratiometric fluorescence sensor is prepared by mixing a ZnMOF solution, a trivalent Eu salt solution, and a Tris-HCl buffer solution. Furthermore, this invention proposes a preparation method for the ratiometric fluorescence sensor, comprising: mixing ZnMOF material with water to obtain a ZnMOF solution; mixing a trivalent Eu salt with water to obtain a trivalent Eu salt solution; mixing a Tris-HCl buffer solution with the trivalent Eu salt solution, and then further mixing it with the ZnMOF solution to obtain the ratiometric fluorescence sensor. In addition, this invention proposes the application of the ratiometric fluorescence sensor in the detection of tetracycline antibiotics. The ratiometric fluorescence sensor proposed in this invention achieves highly sensitive and specific detection of TCs.

The invention provides a ternary complex dual-mode probe and an acetylcholin esterase activity and enzyme inhibitor detection method thereof. The ternary complex dual-mode probe is composed of a CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) system, a manganese dioxide nanoflower-CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) activated ssDNA (ssDNA) (MnO2 NFs-ssDNA) and internal reference fluorescence. When a target to be detected is acetylcholin esterase (AChE), hydrolysis of an acetylthiocholine substrate can be catalyzed, a thiocholine product can be generated, MnO2 NFs can be decomposed to release ssDNA, the trans-cleavage activity of Cas12a can be activated, fluorescence report nucleic acid can be cleaved, a fluorescence signal can be generated, and a more accurate ratio fluorescence signal can be output by taking internal reference fluorescence added into a system as an internal standard; the decomposition of the MnO2 NFs reduces the oxidase-like activity of the MnO2 NFs, and the colorimetric signal for catalyzing the color development of 3, 3 ', 5, 5'-tetramethyl benzidine is reduced; therefore, the higher the AChE activity is, the larger the yield of the thiocholine is, the more thorough the decomposition of the MnO2 NFs is, the stronger the fluorescence signal is, and the weaker the colorimetric signal is. The enzyme inhibitor organophosphorus pesticide can inhibit generation of thiocholine, and then an opposite experiment result appears.

The invention discloses a ratiometric fluorescence immunosensor for detecting D-dimer and a preparation method of the ratiometric fluorescence immunosensor. The preparation method comprises the following core steps: S6, dispersing a Zn / Eu-MOF (at) AgNPs composite material in an ultrapure water solution, and carrying out ultrasonic and oscillation to prepare a Zn / Eu-MOF (at) AgNPs solution; and S7, adding a Zn / Eu-MOF (at) AgNPs solution to ensure the total volume for testing, directly starting detection without any treatment, detecting the fluorescence intensities at 422nm and 616nm in the presence of D-dimers with different concentrations by using a luminoscope, and constructing a working curve of the ratio of the fluorescence intensities at the 422nm and 616nm to the concentration of the D-dimers. The ratio fluorescence immunosensor constructed in the invention has good signal stability and matrix interference resistance in a complex biological sample.

This invention belongs to the field of reactive oxygen species (ROS) detection technology, and discloses a composite near-infrared ratiometric fluorescent probe, its synthesis method, and its application. The probe is composed of a cyanine organic fluorescent dye and bovine serum albumin (BSA). By using urea to disrupt the hydrogen bonds, the BSA protein molecule structure is relaxed and denatured, leading to the extension of the protein's peptide chains. These chains then bind to the synthesized organic compound Hcy-Cl to form the probe Hcy-BSA structure. The ROS level in vivo is detected by ratiometric fluorescence intensity changes. ‑ This invention designs a novel composite near-infrared ratiometric fluorescent probe, which achieves the regulation of ClO through changes in ratiometric fluorescence intensity. ‑ The detection method has advantages such as good selectivity, high stability, good biocompatibility and low toxicity, and is expected to become a powerful auxiliary reagent for the early diagnosis of tumors and Alzheimer's disease.