114 results about "Molecular fluorescence" patented technology

The invention discloses an indole-benzothiadiazole derivative as well as a preparation method and application thereof. The general structural formula of the indole-benzothiadiazole derivative provided by the invention is shown in the specification, wherein R is selected from one of methyl piperazinyl, diethylamino, azetidinyl and pyrrolidinyl. The derivative can be specifically combined and fluorescently labeled with mitochondrial RNA in cells, and has good selectivity, high fluorescence signal-to-noise ratio and excellent anti-interference capability in a complex biological system. Meanwhile, the indole-benzothiadiazole derivative provided by the invention is simple in synthetic route, easily available in raw materials, good in stability and convenient to store and use, can be specifically combined with RNA and generate strong fluorescence response, is suitable for real-time detection and imaging of in-vitro and in-vivo mitochondrial RNA, and is an efficient mitochondrial RNA micromolecular fluorescent probe.

The invention discloses a digital single-molecule enzyme multi-activity characteristic cross-scale heterogeneity dynamic evaluation method, which comprises the following steps: diluting a pre-combined enzyme-template-primer ternary complex to a single-molecule level so as to load the enzyme-template-primer ternary complex into a reaction chamber in a micropore array chip for rolling circle amplification, a molecular beacon is combined with an amplification product to release a fluorescence signal; monitoring and acquiring the fluorescence signal in real time to generate a time-resolved fluorescence intensity curve; extracting a slope parameter of the fluorescence intensity curve so as to obtain a catalytic synthesis rate through conversion calculation for evaluating enzyme activity; the distribution of catalytic synthesis rate values is fitted using an n-fold Gaussian mixture model to obtain a standard deviation for assessing population homogeneity and a coefficient of variation for assessing stability. According to the invention, cross-scale analysis of single-molecule resolution, multi-parameter dynamic association and environmental interference processing can be realized at the same time, and resolution limitation of a traditional analysis technology is broken through by integrating single-molecule fluorescence tracking and population statistics.

The invention belongs to the field of molecular fluorescent probes, and particularly discloses a near-infrared fluorescent probe of quinone oxidoreductase 1 (NAD (P) H: quinone oxidoreductase 1, NQO1) with an in-situ covalent anchoring function and a preparation method of the near-infrared fluorescent probe. According to the probe, dicyanoisophorone is used as a core fluorophore, an aldehyde group is used as an NQO1 covalent anchoring group, and 3-methyl-3-(2, 4, 5-trimethyl-3, 6-dioxocyclohex-1, 4-diene-1-yl) butyrate is used as a recognition group of NQO1. The invention also provides an application of the near-infrared fluorescent probe with the in-situ covalent anchoring NQO1. Compared with other probes, the probe is simple in synthesis method and suitable for industrial production, and has high sensitivity, high selectivity and good biocompatibility in NQO1 detection. The fluorescent probe disclosed by the invention can realize covalent labeling and in-situ imaging functions after target NQO1 recognition response. Long-time in-situ tracking and imaging can be carried out on tumor cells and tissues by monitoring the NQO1 level, and a simple and effective method is provided for accurate detection of tumor disease related protease.

The application belongs to the field of new application of functional proteins and mutants thereof, and discloses application of sugarcane ScCBS protein and key domain deletion mutants thereof. The nucleotide sequence of the sugarcane ScCBS protein is shown as SEQ ID NO:1, and the amino acid sequence is shown as SEQ ID NO:2. The key domain deletion mutants of the ScCBS protein are ScCBS△motif1, ScCBS△motif3, ScCBS△motif4 and ScCBS△motif9, which respectively lack 28, 50, 49 and 29 amino acids. The application proves that the ScCBS protein can interact with SCSMV P1 and inhibit the RNA silencing suppressor activity by means of yeast two-hybrid, two-molecular fluorescence complementary experiment and agrobacterium transient expression system; the four mutants all lose the interaction and inhibition activity. Therefore, the ScCBS protein and the key domain deletion mutants thereof can be used for cultivating excellent SCSMV-resistant materials, and have wide application prospects in sugarcane disease-resistant molecular breeding.

The invention discloses application of a downstream transcription factor ONAC131 of an SL signal channel in improving the antiviral property of rice, and belongs to the technical field of biology. Experiments such as transcriptome sequencing screening, yeast two-hybridization and bimolecular fluorescence complementation verify that ONAC131 is an SL downstream response factor and can interact with MID1 to jointly regulate and control expression of RDR1 and RDR6 and activate an antiviral RNAi pathway. Overexpression of ONAC131 can enhance the resistance of rice to grass stunt virus (RGSV), and otherwise, deletion of ONAC131 can weaken the antiviral effect of rice. The gene supplements an SL downstream regulation framework, provides a new target for rice antiviral molecular breeding, and assists in breeding of new varieties of high-yield and high-resistance rice.

The invention discloses photochromic supramolecular fluorescent ink as well as a preparation method and application thereof in fluorescent falsification prevention. The photochromic supramolecular fluorescent ink comprises an aqueous solution of a photochromic organic compound and an aqueous solution of gamma-cyclodextrin for treating a substrate, the structure of the photochromic organic compound is as shown in formula I. The photochromic supramolecular fluorescent ink disclosed by the invention can realize high-precision and high-stability fluorescent pattern printing, and the unique fluorescence change characteristic of the photochromic supramolecular fluorescent ink provides extremely high safety and recognition for an anti-counterfeiting mark, so that the anti-counterfeiting mark is difficult to copy or tamper; the method can be widely applied to the fields of various anti-counterfeiting files, bills, product packaging and the like.

The invention provides a biomarker detection method which comprises the following steps: carrying out fluorescence labeling on a specific biomarker in a biological sample, and carrying out single-molecule fluorescence imaging on the biomarker to obtain multiple frames of original microscopic fluorescence images; and analyzing and processing the multiple frames of original microscopic fluorescence images so as to extract the super-resolution distribution characteristic information of the specific biomarker on the surface of the biological sample. The method comprises the following steps: processing an original microscopic fluorescence image to obtain positioning table data; rendering positioning points in the positioning table data to generate a super-resolution image; performing convolution operation, opening operation, convolution filtering and region segmentation on the super-resolution image to calculate the area of cells, the number of clusters and the area of a single cluster, determining the density of the clusters and the area ratio of the clusters by using the two, and calculating the closest distance between the clusters by using the center points of the clusters; and the accuracy of a biomarker detection result is greatly improved.

The application discloses a tryptamine detection method based on triple emission MOFs and a smart phone. A rare earth metal organic framework (AP-Eu) is used as a luminescent matrix, and a fluorescent guest molecule fluorescein-5-isothiocyanate (FITC) is post-modified to obtain a ratio fluorescent material with triple emission characteristics. Competitive absorption of ligands and tryptamine, pH response of FITC and hydrogen bonding are used to realize fluorescence signal regulation, and then high-sensitivity and high-selectivity fluorescence recognition of tryptamine is realized. The method is further applied to quantitative detection of tryptamine in beer samples, visualization detection of foam and on-site rapid detection assisted by a mobile phone APP. The application provides a safe and efficient tryptamine detection and fluorescence sensing method, and significantly improves detection accuracy and on-site applicability.

The invention discloses a supramolecular fluorescent probe as well as a preparation method and application thereof, and belongs to the technical field of nano material application. The supramolecular fluorescent probe is formed by compounding gold nanoclusters and a bovine serum albumin solution, and the concentration ratio of the gold nanoclusters to the bovine serum albumin solution is (1-2): (2-4). The invention further discloses a preparation method of the supramolecular fluorescent probe and application of the supramolecular fluorescent probe. A fluorescent sensing system of the supramolecular fluorescent probe based on the gold nanocluster material and the bovine serum albumin has excellent selectivity and sensitivity on cypermethrin pesticide, interference of other impurities can be effectively avoided, and response is fast.

The invention discloses a self-feedback intelligent electrochemical wastewater treatment platform and a construction method thereof. The platform modularly integrates an electrochemical water treatment unit, a terephthalic acid probe molecular fluorescence sensing unit, a signal acquisition data processing unit and an electro-hydraulic linkage online control unit. All the units work cooperatively, and the electrochemical water treatment unit generates strong oxidizing hydroxyl radical mineralized pollutants; the fluorescence sensing and data processing unit is used for converting. OH specificity into a fluorescence signal by utilizing probe molecules and mapping the fluorescence signal into. OH steady-state equivalent concentration in real time; and the online control unit implements a model prediction control strategy based on concentration feedback, dynamically adjusts the current density, the electrode potential and the wastewater flow, and realizes real-time adaptive matching of the interface mass transfer and the. OH generation rate. According to the invention, electrogenerated. OH on-line monitoring and dynamic closed-loop optimization of operation parameters are realized, deep mineralization, low energy consumption and long-term stable operation are realized, and the method is suitable for engineering and intelligent operation of electrochemical advanced oxidation treatment of industrial wastewater.

The invention belongs to the technical field of fluorescent probes, and particularly relates to a single-molecule fluorescent probe based on a phenothiazine structure as well as a preparation method and application of the single-molecule fluorescent probe. The preparation method comprises the following steps: firstly introducing an alkyl chain to a nitrogen atom of a raw material to obtain the phenothiazine structure-based single-molecule fluorescent probe, then carrying out regioselective formylation on the raw material to obtain the phenothiazine structure-based single-molecule fluorescent probe, then treating the raw material by adopting aluminum trichloride to realize O-demethylation, and finally carrying out intramolecular cyclization reaction on the raw material and 1H-benzimidazole-2-acetonitrile to obtain the phenothiazine structure-based single-molecule fluorescent probe. The single-molecule fluorescent probe based on the phenothiazine structure prepared by the invention is compatible with orthogonal chemical reaction activity and maintains controllable electron transfer, so that different chemical events are converted into specific optical signals, and selective and mechanism specific fluorescent response to phosgene, copper ions and hypochlorite is realized.

The invention discloses a method for detecting the conformational change of an APO-Cascade protein. Through mutation of Cas8 protein amino acid N376 and Cas5 protein K169 in a Casade protein, the obtained Cas8 and Cas5 labeled by non-natural amino acids can maintain functions, and at the same time, the mutant type of the Cas5 / 8 protein can be subjected to fixed-point fluorescence labeling; according to the method, the Cas6 is used as a template, the N end of the Cas6 is further modified with biotin, and a formed Casade compound can be fixed on a biotin-PEG functionalized single-molecule slide, so that the conformation state of the Casade protein can be truly reflected by using single-molecule fluorescence resonance energy transfer, an effective means is provided for in-vitro research on the structure-function relationship of a system in CRISPR / Casade, and the method has a wide application prospect. And the method is of great significance in designing the Cascade protein with optimized properties and enabling the Cascade protein to play new functions.

The invention discloses an i-motif DNA (deoxyribonucleic acid) modified gold nano flare, a preparation method of the i-motif DNA modified gold nano flare and application of the i-motif DNA modified gold nano flare to detection of miRNA, and belongs to the technical field of nano biological materials and molecular diagnosis. The fluorescence probe is formed by assembling gold nanoparticles and an i-motif molecular fluorescence probe, the i-motif molecular fluorescent probe contains four sections of sequences rich in C basic groups and a target miRNA recognition chain, sulfydryl is marked at the 5'end, and fluorescent molecules are marked at the 3 'end. The probe is prepared by adopting a freeze thawing method, the labeling density of the probe is high, in a constructed detection system, the miR-21 detection limit is as low as 1.01 fM, and single-base mutants can be accurately distinguished; the technology does not need complex sample pretreatment and can be directly used for detecting cell total RNA or miRNA in a plasma sample, and the detection result is highly consistent with RT-qPCR; the problems of low marking efficiency and insufficient sensitivity in the prior art are effectively solved, and an innovative tool with high sensitivity, high specificity and clinical suitability is provided for tumor-associated miRNA molecular diagnosis.

The present invention provides an integrated platform for exciting a molecular fluorescence signal, a detection chip, and an optical packaging structure. The integrated platform for exciting the molecular fluorescence signal comprises, arranged in sequence: an input optical coupling structure (1), a first filtering structure (2), an optical beam-splitter tree structure (3), a filtering structure array (4), a fluorescence excitation structure array (5), and an optical coupling-out structure array (6). The detection chip is used for detecting molecular fluorescence and comprises, arranged from bottom to top in sequence: a fluorescence detection layer (103'), a fluorescence collection layer (102'), and a fluorescence excitation layer (101'). The fluorescence excitation layer (101') comprises, arranged in sequence: an input optical coupling structure (1011'), an optical beam-splitter tree structure (1013'), a fluorescence excitation structure array (1014'), and an optical coupling-out structure array (1015'). The fluorescence excitation layer is further provided with an optical feedback structure (1012'), wherein an input end of the optical feedback structure (1012') is connected to a first output end of one branch of the optical beam-splitter tree structure (1013'). The optical packaging structure comprises an optical fiber module (2') and the detection chip (1'). The integrated platform in the present invention incorporates on-chip filters, providing an integrated fluorescence excitation solution capable of suppressing broadband background light arising from spontaneous fluorescence of lasers or waveguides, thereby improving a signal-to-noise ratio. The detection chip and the optical fiber module in the optical packaging structure in the present invention employ a passive optical coupling scheme, thereby facilitating stability of fluorescence signals and reducing complexity of external device optical paths.

The invention relates to a molecular fluorography detection method combined with liquid chromatography, and belongs to the technical field of analysis and detection. The invention aims to solve the technical problems that the high sensitivity is difficult to maintain while the miniaturization of the existing liquid chromatogram fluorescence detector is realized, and a flexible and low-cost detection scheme is lacked. According to the technical scheme, the method is characterized in that after being subjected to liquid chromatography separation, a sample is conveyed to a silica gel coating preparation plate through a polyether-ether-ketone tube to form a detection area; exciting fluorescence by adopting a laser with a first narrow-pass optical filter; acquiring a series of fluorescence images by using an image acquisition unit with a second narrow-pass optical filter; and finally, extracting RGB (Red, Green and Blue) numerical values of a fixed pixel region through computer image processing software, and generating a chromatogram of which the fluorescence intensity changes along with time. The method is mainly used for rapid and high-sensitivity fluorescence detection in the fields of biomedical analysis, environmental monitoring, food safety and the like.

The present invention discloses a small-molecule fluorescent probe for CDK4 / 6, its preparation method, and applications, belonging to the field of biomedicine. The CDK4 / 6 small-molecule fluorescent probe provided by the present invention has a structure represented by Formula (I), a novel probe response group, and good selectivity. The preparation method also features mild reaction conditions, readily available and inexpensive raw materials, and simple operation and post-processing. The probe exhibits high affinity for the CDK4 / 6 protein and high sensitivity.

The application discloses a KRAS G12D A small-molecule fluorescent probe, a preparation method and application thereof, and a structure of the small-molecule fluorescent probe is shown as follows. An activity determination method based on the small-molecule fluorescent probe has the advantages of a simple test system, no need of a complex buffer system, small influence of time and solvent, etc., and can be used for screening of KRAS G12D inhibitors.

The present invention discloses a quinoline-based small-molecule fluorescent probe for hydrogen peroxide and its preparation method. This invention belongs to the field of fluorescent probe technology. The specific structural formula of the fluorescent probe is shown in Formula (I): #imgabs0# The present invention uses 2-methyl-7-hydroxyquinoline as the fluorescent group and 4-bromomethylphenylboronic acid pinacol ester as the recognition group. The prepared fluorescent probe exhibits high sensitivity and selectivity for H2O2 in solution. The preparation method of this fluorescent probe is simple, the raw materials are readily available, and the resulting product is a solid powder that is easy to store. It has broad application prospects and can be used in large-scale production.

The application discloses a new method for quantitatively analyzing interface nucleic acid hybridization reaction and application thereof, and comprises the following steps: S1, constructing a DNA tetrahedron interface; S2, imaging the DNA tetrahedron interface through a total internal reflection fluorescence microscope; S3, realizing real-time monitoring of a hybridization event of the DNA tetrahedron interface by adopting double-color co-localization and analyzing a fluorescence signal; and S4, analyzing hybridization kinetics on the DNA tetrahedron interface by recording changes of the fluorescence signal with time. The application uses the DNA tetrahedron interface for single-molecule fluorescence imaging, can realize real-time monitoring of a single nucleic acid molecule hybridization event, improve detection sensitivity and specificity, accurately analyze kinetic parameters of a hybridization reaction, help realize more accurate performance evaluation of a nucleic acid sensor, has important significance for design and optimization of the nucleic acid sensor, and thus plays a greater role in the fields of clinical diagnosis, environmental monitoring and food safety.

The present invention relates to the technical field of fluorescent active substances, and in particular to a zinc (II)-based metal organic framework crystalline material, its preparation method, and application. The molecular formula of the zinc (II)-based metal organic framework crystalline material of the present invention is [Zn(NH2-BDC)2(BMIP)2] n The zinc(II) ion serves as the connecting node, and BMIP and NH2-BDC ligands serve as bridging ligands to form a three-dimensional structure. The asymmetric structural unit of the crystal consists of a BMIP ligand and a deprotonated 2-aminoterephthalic acid ligand. The zinc ion has a four-coordinated, asymmetric tetrahedral configuration. A divalent zinc ion fluorescent sensing material can be prepared using a one-pot solvothermal reaction. The zinc(II) fluorescent sensing material exhibits a strong fluorescence emission spectrum and is suitable for applications in molecular fluorescent probes and metal ion detection.

The present invention discloses a rare earth supramolecular fluorescent aggregate, a preparation method, and an application thereof, belonging to the field of analytical chemistry technology. The preparation method of the rare earth supramolecular fluorescent aggregate comprises the following steps: mixing a rare earth salt solution and a 2,6-pyridinedicarboxylic acid solution to conduct a coordination reaction to obtain a mixed solution A; mixing a polyoxyethylene polyoxypropylene ether triblock polymer solution and a carboxymethyl β-cyclodextrin solution, and then conducting a host-guest inclusion complex reaction to obtain a mixed solution B; and mixing mixed solutions A and B to cause coordination and supramolecular aggregation reactions to obtain a rare earth supramolecular fluorescent aggregate. The preparation method of the present invention is simple and easy, and the prepared supramolecular fluorescent aggregate has excellent fluorescence properties and stimulus response characteristics.

The application discloses a kind of digital single molecule enzyme multi-activity characteristic cross-scale heterogeneity dynamic evaluation methods, comprising: the enzyme-template-primer ternary complex of pre-combination completion is diluted to single molecule level to be loaded into the reaction chamber in microwell array chip to carry out rolling circle amplification, and utilize molecular beacon and the fluorescence signal released by amplification product combination;Real-time monitoring and obtaining the fluorescence signal to generate time-resolved fluorescence intensity curve;The slope parameter of the fluorescence intensity curve is extracted to obtain the catalytic synthesis rate by conversion calculation for evaluating enzyme activity;The catalytic synthesis rate value distribution is fitted using n times Gaussian mixture model to obtain the standard deviation for evaluating population uniformity and the coefficient of variation for evaluating stability.The application can realize single molecule resolution, multi-parameter dynamic correlation and environmental interference processing cross-scale analysis simultaneously, and break through the resolution limit of traditional analysis technology by integrating single molecule fluorescence tracking and population statistics.

The invention belongs to the technical field of bio-photonics, and particularly relates to a single molecule detection method for marking shewanella electron transfer and application of the single molecule detection method. The method comprises the following steps: adding a fluorescent probe into a shewanella sample by adopting a single-molecule super-resolution fluorescence microscope technology, specifically binding the fluorescent probe with shewanella cells, exciting the fluorescent probe to emit fluorescence, and carrying out single-molecule fluorescence labeling on the shewanella cells. According to the present invention, the single-molecule super-resolution fluorescence microscope technology and the nile blue specific combination are adopted to achieve the single-molecule-level high temporal-spatial resolution monitoring, the binding site and the dynamic change of the nile blue on the shewanella cells can be accurately observed, the nano-scale resolution visual data can be provided for the research of the cell electron transfer process, and the application prospect is broad. The detection precision is obviously improved; the electron transfer activity of shewanella cells can be analyzed by detecting the change of a Nile blue fluorescence signal, and the method has a wide application prospect in the fields of bioremediation, energy production and the like.

The invention belongs to the field of organic molecule fluorescent probes, and relates to a small molecule fluorescent probe HX which realizes the integration of diagnosis and treatment by monitoring related physical properties of a tumor microenvironment and photodynamic therapy of tumors. A tumor microenvironment of a solid tumor generally has the characteristics of low pH, high viscosity, low oxygen and the like, and has important significance on real-time monitoring and effective inhibition of tumor tissues on the basis of characteristic parameters of tumor parts. Therefore, a near-infrared fluorescent probe HX is designed, the probe does not respond to surrounding viscosity change in a high pH value environment, however, in a tumor low pH value microenvironment, a donor-pi-receptor (Donor-pi-acceptor, D-pi-A) structure of the probe is opened, and the sensitive viscosity response characteristic is shown, so that the dynamic monitoring of the tumor microenvironment is realized. Besides, through structural optimization, the probe is proved to be capable of serving as a photosensitizer with I-type reaction and used for tumor tissue photodynamic therapy under the hypoxic condition. By means of a mouse living tumor model, we prove that the probe HX not only has the capability of identifying tumor tissues and normal tissues, but also has an excellent tumor inhibition effect and good biocompatibility under the hypoxic condition, and a new technology is provided for integrated design of diagnosis and treatment of tumor diseases. # imgabs0 #

The application discloses a KRAS small-molecule fluorescent probe and a preparation method and application thereof, a structural general formula of the KRAS small-molecule fluorescent probe is shown as formula (I), and the fluorescence polarization activity determination method based on the small-molecule fluorescent probe has the advantages of simple test system, less required protein types, low dosage, no need of a complex buffer system, small influence of time and solvent and the like compared with HTRF. The method can be used for screening of KRAS wild type and various mutant inhibitors including but not limited to G12C, G12V, G12D, G12A, G12S and G12R, and has a good application prospect.

This invention discloses a triphenylamine-based D-A type AIE molecule targeting STAT3, its preparation method, and its application in the diagnosis and treatment of colorectal cancer. This molecule uses triphenylamine as a donor and pyridinium as an acceptor, linked by a rigid conjugated trans-vinyl group, exhibiting aggregation-induced emission (AIE) properties. The preparation method employs a Knoevenagel condensation reaction, using 4-(diphenylamino)benzaldehyde and 1,4-dimethylpyridinium iodide as raw materials, and proceeds via a nucleophilic addition-dehydration reaction catalyzed by pyrrolidine, with a yield of 50±3% and a purity ≥98%. This molecule exhibits a fluorescence emission wavelength of 640 nm, demonstrates a significant AIE effect, can penetrate the colorectal cancer cell membrane and specifically aggregate, and shows activity against the IC50 of HCT116 and DLD1 cells. 50 The concentrations were 6.41 μM and 11.46 μM, respectively, which exerted anti-tumor effects by inhibiting STAT3 phosphorylation, enabling integrated diagnosis and treatment of colorectal cancer.

The invention discloses a double-terminal fluorescence labeled polymer as well as a preparation method and application thereof. The structural formula of the double-terminal fluorescence labeled polymer is shown as a formula V. In the formula V, n is 30-300, and x is 1-10. The preparation method comprises the following steps: carrying out ATRP (Atom Transfer Radical Polymerization) active polymerization reaction on a monomer by taking 2-bromo-2-methyl propionate 2-hydroxyethyl ester with hydroxyl at the tail end as an initiator to obtain a compound of which the tail end is terminated by hydroxyl and bromo; a hydroxyl terminal in the compound reacts with a perylene fluorescent dye shown in a formula II, a bromine terminal is subjected to an azidation reaction and then is subjected to a click chemical reaction with an ATTO647N dye, and the double-terminal fluorescence labeled polymer shown in a formula V is obtained. The double-fluorescent-molecule end-capped polymer disclosed by the invention has an FRET effect; the double-fluorescent-molecule-terminated polymer can realize single-molecule fluorescence microscopic imaging, and has important significance on basic researches such as micro-nano structure evolution of characterization and analysis materials and the like.

The invention discloses a flavonoid fluorescent dye, a supramolecular fluorescent probe, a preparation method of the supramolecular fluorescent probe and a pyriproxyfen detection method. The probe is constructed by spontaneously assembling the albumin derivative and the flavonoid fluorescent dye in a buffer solution. The detection mechanism is shown as follows: the flavonoid dye presents characteristic red fluorescence in a free state, and obvious fluorescence blue shift is triggered after the flavonoid dye is combined with albumin. When pyriproxyfen is introduced into the system, hydrophobic molecules enter an albumin hydrophobic cavity in a competitive binding manner, so that dye molecules have a replacement effect. In the process, along with the bidirectional response of a fluorescence signal, namely, the yellow fluorescence intensity and the pyriproxyfen concentration are in negative correlation, and the reconstructed dye aggregation state triggers the enhancement of a green fluorescence channel signal, so that the quantitative conversion of the fluorescence chroma of the solution from yellow to green is finally realized. Based on the ratio-type fluorescence signal, the probe system has an obvious colorimetric effect when being used for detecting pyriproxyfen in environment, food and the like, and the color change can be directly observed by naked eyes.

A method for detecting labile zinc (Zn2+) in a biological material is provided herein, the method including: (a) contacting the biological material with a composition including NapBu-BPEA; and (b) imaging the biological material via molecular fluorescence imaging to detect the labile zinc in the biological material. Also provided herein are methods for morphology-correlated detection of labile zinc localization in a subcellular organelle of a living cell and methods for tracking a change in labile zinc localization in a biological material.

The application discloses a single-molecule immunodetection chip based on height limiting and a detection method. The chip comprises a substrate and a detection flow channel formed in the substrate. The detection flow channel comprises: an oil-phase sampling port and a water-phase sampling port; a cross-shaped droplet generator which is connected with the oil-phase sampling port and the water-phase sampling port and is used for generating droplets; and a flat detection cavity, the height H of the detection cavity is less than the diameter D of the droplets in a free state, so that the droplets generated in the droplet generator are extruded in the up-down direction and are changed from spherical shape to flat pie shape after entering the detection cavity. In the application, the flattened droplets formed by the single-molecule immunodetection chip can lock all single-molecule fluorescent centers in a space with a thickness of only 30 microns, which can completely match the large numerical aperture objective focal depth of a high-performance camera. In the application, physical support and flow resistance guidance are provided by the micro-column array, so that the droplets can almost remain static at the imaging moment, and motion blur is completely eliminated.