101 results about "Fluorescent reporter" patented technology

The invention relates to the technical field of molecular biology and pathogenic microorganism detection, and discloses a Klebsiella pneumoniae and Escherichia coli synchronous detection method based on RPA-CRISPR / Cas12a and application, and the method comprises the following steps: extracting DNA from a sample, carrying out isothermal amplification by adopting an RPA primer designed aiming at a Klebsiella pneumoniae rcsA gene and an Escherichia coli uriA gene, and carrying out amplification by adopting an RPA primer designed aiming at a Klebsiella pneumoniae RcsA gene and an Escherichia coli uriA gene; a detection system containing Cas12a enzyme, crRNA and a fluorescence report substrate is constructed, and a result is interpreted through a fluorescence or lateral flow chromatography test strip. Detection can be completed within 70 minutes at the constant temperature of 37 DEG C, the sensitivity reaches 5 * 10 copies / mu L, the specificity is high, no cross reaction exists, the kit is suitable for clinical early screening, hospital infection monitoring and on-site POCT application, and an efficient and reliable new tool is provided for pathogen diagnosis.

The invention discloses application of novel reverse transcriptase and related fusion protein of the novel reverse transcriptase in plant-guided editing. Candidate RT protein is obtained through systematic mining from a public database, novel reverse transcriptase cl1 with activity is screened out in combination with a fluorescence report system, and a guided editing system suitable for plants is constructed. The system tests in wheat protoplast, and verifies the editing activity of cl1 to a plurality of endogenous targets. Further combining with protein structure prediction and rational design point mutation optimization, the cl1 mutant with higher editing efficiency is obtained, and the method can be applied to accurate and effective editing of plant genomes and plant breeding and improvement.

This invention discloses a genetic transformation and gene editing method applicable to multiple sesquiterpene species, belonging to the field of plant genetic transformation and gene editing technology. The method uses the cotyledonary nodes of sterile seedlings of the sesquiterpene genus as explants, and introduces an optimized pScEF1α-Cas9 gene editing transformation vector using Agrobacterium infection. Regenerated plants are obtained through recovery culture, selection culture, and rooting culture. The vector contains four gene expression units: pScEF1α:Cas9, pGmU6:sgRNA, pGmUBI:DsRed2, and pCaMV35S:HygR. In vivo screening is further performed using the DsRed2 fluorescent reporter gene, and the gene-edited plants are identified by molecular detection. This method is applicable to common sesquiterpene, stem-nodled sesquiterpene, and spiny sesquiterpene, and has advantages such as strong species versatility, high transformation efficiency, short cycle, visualized screening, and high positive rate, providing efficient technical support for gene function research and genetic improvement of sesquiterpene species.

This invention provides a method for constructing a fluorescently traced mouse model and its application in the sorting of Mcpt4-positive and negative mast cells. First, the Cre gene is knocked into the Mcpt4 gene sequence of C57BL / 6 mice using CRISPR / Cas9 technology. Then, through animal hybridization and Cre-loxP recombination technology, a fluorescently traced mouse model of Mcpt4-positive mast cells is obtained. The fluorescently traced mouse model possesses a dual-fluorescent reporter gene system consisting of the red fluorescent protein tdTomato and the green fluorescent protein ZsGreen. Mcpt4-positive mast cells exhibit red fluorescence, while other Mcpt4-negative cells exhibit green fluorescence. Using this fluorescently traced mouse model, Mcpt4-positive and negative mast cells can be rapidly, accurately, and effectively sorted, providing a reliable technical basis for exploring the roles and mechanisms of Mcpt4-positive and negative mast cells in immune responses.

In one aspect, a method of treating an NK cell to induce a gene edit. The method may include contacting an NK cell with a transfection composition including poly-L-glutamic acid (y- PGA), a single-stranded oligo deoxynucleotide (ssODN) enhancer, or a combination thereof; contacting the NK cell with an editing composition including: a DNA-PK inhibitor, and an HD AC inhibitor; electroporating the NK cell; and contacting the NK cell with a recovery composition including DNase I. In another aspect, a method of preparing an engineered NK cell comprising a fluorescent reporter at an endogenous locus. In another aspect, a method of treating an NK cell to introduce an exogenous nucleic acid.

The invention relates to a RAA-CRISPRCas13a method for detecting iridovirus fluorescence of micropterus salmoides, and relates to the technical field of biological detection.The method comprises the following steps that an RAA primer pair and guide crRNA are designed and synthesized based on a virus specific gene sequence; the method comprises the following steps: constructing a single-tube reaction system containing an RAA amplification component, Cas13a protein, crRNA and a fluorescent reporter molecule; after sample nucleic acid is added, constant-temperature incubation is carried out for 15-30 minutes at 37-42 DEG C, an RAA amplification product activates trans-cleavage activity of Cas13a, and a cleavage reporter molecule generates a fluorescence signal; and virus judgment is realized by detecting a fluorescence signal. According to the method, isothermal amplification and CRISPR detection are efficiently integrated through a single-tube reaction system, and the method has the advantages of being easy and convenient to operate, rapid in detection, high in sensitivity and high in specificity and is suitable for on-site high-throughput screening.

The application provides a double-stranded walking type DNA nanomachine and a preparation method and application thereof, and relates to the technical field of fluorescent analysis and detection.The double-stranded walking type DNA nanomachine for ctDNA fluorescent detection comprises a gold nanoparticle carrier, an anchor probe, a FAM fluorescent reporter probe, a double-stranded walking arm, a Cas12a protein and a crRNA to form a ribonucleoprotein complex.The walking arm of a conventional CRISPR / Cas12a nanomachine is a DNA single-stranded structure, which is easily cut in trans by activated Cas12a, thereby reducing the stability and sensitivity of the nanomachine.The application introduces a double-stranded DNA structure into the walking arm design to replace the conventional DNA single-stranded walking arm, constructs a double-stranded walking type three-dimensional DNA CRISPR / Cas12a nanomachine, effectively resists the reverse cutting of Cas12a on the walking arm, maintains the structural integrity and functional stability of the nanomachine, and greatly improves the detection sensitivity and specificity of lung cancer ctDNA, thereby having a good clinical application prospect.

This invention discloses a target-gated ratiometric pH sensor based on a dual CRISPR system of tetrahedral framework nucleic acids, belonging to the fields of biomedicine and nucleic acid nanotechnology. The sensor uses tetrahedral framework nucleic acids as a rigid scaffold, precisely assembling Cas12a, Cas13a, and their corresponding fluorescent reporter molecules in a 1:1 stoichiometric ratio. Their orthogonal pH responses form the basis of the ratiometric sensing. Target recognition-pH sensing logic gating is achieved through target-specific crRNA design. Cholesterol modification allows for stable anchoring on the lipid membrane surface. This invention also discloses the sensor's fabrication, membrane anchoring, pH monitoring, and target-gated function implementation methods. This sensor possesses advantages such as high-precision ratio measurement, accurate spatial arrangement, high specificity, stable membrane anchoring, and a wide pH response range, and can be used for precise monitoring of pH dynamics at biomembrane interfaces and during extracellular vesicle fusion.

The application discloses a method for synthesizing reverse transcriptase: obtaining a target reverse transcriptase expression sequence based on database primary screening; obtaining a candidate reverse transcriptase expression sequence by using a fluorescent reporter system to rescreen the target reverse transcriptase expression sequence; and determining a synthetic reverse transcriptase expression sequence by using the fluorescent reporter system after optimizing the candidate reverse transcriptase expression sequence. The application further screens a plurality of natural or engineered small reverse transcriptases in view of the bottleneck of the prior art, and verifies the applicability of the reverse transcriptases in prime editing. The technology is expected to break through the application limitation of the existing prime editing system, and provide more efficient and safer precise editing tools for the fields of genetic disease treatment, agricultural breeding and synthetic biology.

A vibrationally enhanced fluorescence microscopy system includes a narrowband pulsed mid-infrared laser configured to excite selected chemical bond vibrations in a sample. A continuous-wave visible laser is coaligned with the mid-infrared laser and configured to induce fluorescence from at least one fluorescent reporter bound to the sample. An external pulse generator temporally synchronizes emission of the mid-infrared pulses with emission of the visible laser. A reflective objective is arranged to deliver the mid-infrared pulses to a focal plane within the sample. A water-immersion objective is coaxially aligned with the reflective objective and arranged to collect the fluorescence from the focal plane. A photon-counting detector is coupled to receive the collected fluorescence. Control electronics are configured to output a vibrational-contrast signal derived from counts produced by the photon-counting detector.

The invention discloses an influenza reporter virus carrying a fluorescent RNA aptamer and a construction method and application thereof, and the influenza reporter virus carrying the fluorescent RNA aptamer is obtained by introducing a termination codon TAA into the 328th nucleotide of an ORF region of an NS1 gene on the basis of a genome of an influenza A virus and terminating in advance, then introducing a terminating codon TAA into the 328th nucleotide of the ORF region of the NS1 gene of the influenza A virus; original nucleotides at the 328-480 sites are replaced by forward or reverse RNA aptamers, and the RNA aptamer is obtained. The influenza reporter virus carrying the fluorescent RNA aptamer constructed by the invention also has the characteristics of good virus replication ability, high RNA imaging sensitivity and good specificity on the basis of stable inheritance, can be used for real-time visual observation of virus RNA, and is used for research on virus replication cycle and molecular mechanism related to the virus RNA. Besides, the construction method of the influenza reporter virus carrying the fluorescent RNA aptamer can also be applied to construction of RNA fluorescent reporter viruses of other subtype influenza viruses such as H3N2 and H5N1, and an important tool is provided for real-time tracing of corresponding virus RNA.

This invention relates to the field of biomedical detection technology, and discloses a bitetrahedral framework nucleic acid TDN cascade amplification system and its application, including TDN-1 and TDN-2. TDN-1 has a hairpin H1 containing a fluorescent reporter group attached to its surface, and TDN-2 has a hairpin H2 attached to its surface. The sequences of H1 and H2 are designed to undergo an alternating hybridization chain reaction triggered by target mRNA. This scheme relies on the synergistic effect of TDN structural anchoring and precise hairpin probe sequence design to overcome the technical defects of traditional free HCR hairpins in living cells, such as poor stability, low reaction efficiency, and non-specific triggering, achieving more efficient and specific intracellular signal amplification. Furthermore, it enables highly specific and sensitive in-situ imaging and dynamic tracking of low-abundance mRNAs such as c-Myc in single living cells, effectively solving the problems of insufficient detection sensitivity and false positives caused by the inability of traditional detection methods to effectively enrich targets and the low efficiency and high background of traditional HCR and other signal amplification technologies in intracellular applications.

The invention discloses a dermatophyte nucleic acid rapid detection kit, which comprises: a CRISPR / Cas12a reaction system, which comprises a Cas12a protein and a corresponding crRNA; the fluorescent reporter probe is provided with a 5 '-end FAM label and a 3'-end biotin label; an anti-FAM antibody-fluorescent quantum dot conjugate; the quantum dot immunochromatography test strip comprises a sample pad, a nitrocellulose membrane and an absorption pad, and the nitrocellulose membrane is provided with a test line and a control line; the control line is coated with streptavidin, and the test line is coated with goat anti-mouse IgG. The invention further discloses a corresponding detection method. Detection can be completed within 1 h, operation is easy and convenient, detection sensitivity and specificity are high, and the method is suitable for rapid detection and field application of dermatophyte.

The invention provides a CRISPR-Cas12a-based target pathogen rapid detection method, which comprises: S1, determining an LAMP primer group, and carrying out isothermal amplification on a target sequence of a target pathogen in a to-be-detected sample through the LAMP primer group; s2, determining crRNA, a fluorescent reporter probe and Cas12a protein matched with the target sequence, and detecting the target sequence through the crRNA, the fluorescent reporter probe and the Cas12a protein to judge whether the target sequence of the target pathogen exists in the target sample or not; the LAMP primer group comprises sequences as shown in SEQ ID NO.1-SEQ ID NO.12, and the crRNA comprises sequences as shown in SEQ ID NO.13-SEQ ID NO.15. According to the invention, high-sensitivity and high-specificity detection of target nucleic acid is realized, the detection accuracy is high, the operation is simple and rapid, and the requirements on instruments and equipment are low.

The invention discloses a green fluorescence report system for screening a Listeria monocytogenes quorum sensing inhibitor as well as a construction method and application of the green fluorescence report system. The report system is constructed through the following steps: synthesizing a DNA fragment according to a listeria monocytogenes AGR system pII promoter sequence, connecting the DNA fragment with a green fluorescent protein pEGFP plasmid, amplifying an EGFP-pII target fragment through PCR, and connecting the target fragment to a pKSV7 shuttle vector plasmid through homologous recombination to obtain a pKSV7-EGFP-pII plasmid, and then transferring the gene into a competent cell of listeria monocytogenes ATCC BAA-679, and screening to obtain a report system. The report system disclosed by the invention can be used for intuitively evaluating the expression condition of the quorum sensing system of the listeria monocytogenes and screening out the quorum sensing inhibitor.

The application relates to a detection method based on a nano-addressable DNA origami platform combined with a CRISPR technology, in particular, a crRNA chain and a DNA fluorescent reporter molecule chain are hybridized at a preset spatial site through an address sequence, Cas12a is combined with the crRNA at a specific region, the activated Cas12a cuts a substrate, the fluorescent signal on the DNA origami changes, and thus the target nucleic acid is detected. The method of the application is suitable for various targets, and realizes simultaneous detection of multiple targets in a one-pot method.

The invention discloses a method for visually detecting mandarin fish iridovirus and infectious spleen and kidney necrosis virus based on RPA-CRISPR Cas12a / Cas13a, and belongs to the technical field of biological diagnosis. According to the method, a CRISPR / Cas system is combined with RPA amplification, a fluorescent reporter and a test strip are used for naked eye observation, and the method combines the advantages of different isothermal amplification technologies, has the advantages of short detection time, high specificity, no cross reaction, high sensitivity and the like, realizes rapid and accurate diagnosis of the two pathogens, and has a good application prospect. Important technical support is provided for prevention and control of mandarin fish diseases.

The application discloses a thermus butyricum transcriptional regulatory protein TrpR mutant screening and application, and belongs to the technical field of genetic engineering. Through screening of the TrpR mutant, favorable modification of the thermus butyricum transcriptional regulatory protein TrpR is realized, so that the specificity of the response of the thermus butyricum transcriptional regulatory protein TrpR to 5,6-dihydroxyindole is enhanced, a special biosensor is constructed by combining with a fluorescent reporter gene, effective detection of the 5,6-dihydroxyindole content is realized, and the efficiency and purity of extraction of a target component are ensured, thereby laying a solid foundation for subsequent application and research.

The invention belongs to the field of synthetic biology and metabolic engineering, and discloses a screening method and application of a microbial strain with high yield of ergothioneine, a promoter (such as PECL1, PBSC5, PEDC2 and the like) responding to ergothioneine is screened through transcriptomics analysis based on saccharomyces cerevisiae, and the promoter can present high sensitivity and linear response under 0-1000 mg / L of ergothioneine. The strain is used for driving fluorescent protein gene expression, a fluorescence report strain is constructed, the strain can rapidly and sensitively detect the concentration of ergothioneine in fermentation liquor by virtue of fluorescence signal change, and high-yield strains are efficiently screened. The method overcomes the problems of low flux, long period, low sensitivity and the like of traditional screening, and the fluorescence signal intensity is in significant linear correlation with the ergothioneine concentration. And the perforated plate and the microplate reader are used for automatic high-throughput screening, so that the efficiency is improved, the resource consumption is reduced, effective support is provided for production optimization of ergothioneine, and the application prospect is wide.

The invention provides a core-shell hydrogel microbead sensing platform as well as a preparation method and application thereof, and belongs to the technical field of synthetic biology and environmental monitoring. The invention provides an engineering sensing microorganism. The engineering sensing microorganism comprises a recombinant vector, the recombinant vector contains a gene expression cassette with target substance response, transformation and report functions; the gene expression cassette comprises a coding gene of a transcription factor ChpR, a coding gene of a fluorescent reporter protein GFP and a coding gene of a chlorpyrifos degrading enzyme, and the gene expression cassette is assembled into a sensing gene line and then introduced into microorganisms to construct the whole-cell biosensor for detecting chlorpyrifos and a metabolite 3, 5, 6-trichloro-2-pyridinol thereof. According to the invention, the chlorpyrifos degradation conversion module is assembled and optimized, and the performance of the sensor is obviously improved. The core-shell hydrogel microbead prepared by the invention can ensure the biological safety and improve the stability of a sensor, and is suitable for high-sensitivity detection of trace chlorpyrifos residues in fruits, vegetables and environmental samples.

The application discloses a RPA-CRISPR / Cas12a-based rapid visual detection method for manning's paragonimus. The method takes the mitochondrial cox1 gene as a target, screens a conservative region through sequence alignment, designs specific crRNA and RPA primers, optimizes Cas12a, crRNA, a fluorescent reporter molecule and a buffer system, and constructs a recombinase polymerase amplification combined CRISPR / Cas12a trans-cleavage detection system. Two visual detection strategies, visual fluorescence and lateral flow chromatography, are adopted, so that instant detection can be realized without large instruments and professional personnel, and the method has the advantages of high sensitivity and good specificity, can accurately detect manning's paragonimus DNA, cat and dog feces and blood samples, and brain schistosomiasis cerebrospinal fluid samples, and is suitable for on-site rapid screening.

This invention discloses an RPA-T7-CRISPR-based absolute quantification chip for ctDNA. The system employs a microarray digital partitioning structure as the reaction carrier, integrating an RPA isothermal amplification system, a T7 transcription amplification system, and a CRISPR / Cas13a specific recognition system within multiple independent reaction units. After the sample enters the chip, sample allocation, target nucleic acid amplification, transcription amplification, fluorescent reporter molecule cleavage, and signal reading are completed in a closed chip flow path. Then, based on fluorescence microscopy observation, the number of positive reaction units is counted, and their percentage of the absolute copy number of ctDNA in the sample is calculated. This chip, with its digital microarray partitioning and closed flow path design, integrates nucleic acid isothermal amplification, transcription amplification, specific recognition, and fluorescence readout, achieving rapid and highly sensitive absolute quantification of low-abundance ctDNA.

The invention discloses an RPA-CRISPR / Cas-based rapid detection method for echinococcus shikonii, and belongs to the technical field of molecular diagnosis. The method comprises the following steps: extracting DNA of a sample to be detected; the specific primers are used for RPA isothermal amplification, a reaction system comprises a buffer solution, upstream and downstream primers, RPA enzyme, magnesium acetate and template DNA, and reaction is carried out at 39 DEG C for 20 minutes; and mixing the amplification product with LbCas12a protein, sgRNA and a fluorescence report probe, carrying out CRISPR / Cas reaction at 37 DEG C for 30 minutes, and judging the result through a real-time fluorescence signal. According to the method, constant-temperature rapid amplification is realized by utilizing RPA, high-sensitivity and high-specificity detection of the echinococcus shikonii can be realized under the field condition by combining high-specificity recognition and cleavage activity of CRISPR / Cas12a, the sensitivity reaches a single-digit copy number, and the method is simple and convenient to operate, does not need a complex instrument and is suitable for primary medical treatment and field quarantine.

The invention discloses a rapid detection method for echinococcus granulosus based on RPA-CRISPR / Cas, and belongs to the technical field of molecular diagnosis. The method comprises the following steps: extracting DNA of a sample to be detected; the specific primers are used for RPA isothermal amplification, a reaction system contains a buffer solution, upstream and downstream primers, RPA enzyme, magnesium acetate and template DNA, and reaction is carried out at 39 DEG C for 20 minutes; and mixing the amplification product with LbCas12a protein, sgRNA and a fluorescence report probe, carrying out CRISPR / Cas reaction at 37 DEG C for 30 minutes, and judging the result through a real-time fluorescence signal. Constant-temperature rapid amplification is achieved through RPA, high-sensitivity and high-specificity detection of the echinococcus granulosus can be achieved under the site condition by combining high-specificity recognition and trans-cleavage activity of CRISPR / Cas12a, the sensitivity reaches the single-site copy number, operation is easy and convenient, complex temperature control equipment is not needed, and the method is suitable for primary medical treatment and site quarantine.

The present invention relates to a device for detecting a target molecule (2) and / or measuring the concentration of the target molecule (2), comprising a substrate having covalently bound graft molecules on its surface, at least one receptor (11) covalently bound to a polypeptide (12), and two fluorescent dyes F. a and F b and at least one fluorescent probe (1) containing a fluorescent dye F a binds to the receptor (11) and the fluorescent dye F b is bound to a polypeptide (12); and the fluorescent dye F a and F b form a FRET donor / acceptor pair; and a polypeptide (12) is covalently attached to the graft molecule. The present invention also relates to fluorescent probes and methods for detecting and / or measuring the concentration of target molecules.

The invention provides a method for detecting Ggt in gene mutation. The invention relates to a lock type probe for detecting A mutation, which comprises a recognition sequence complementary with a target p53 R175H and a sequence recognized by CRISPR / Cas12a, and is modified with 8-oxoguanine. The invention also provides a Ggt based on the combination of the Fpg enzyme and CRISPR / Cas12a (clustered regularly interspaced short palindromic repeats / CRISPR / Cas12a). The universal type detection kit for A mutation comprises the lock-type probe, a fluorescence report probe, a primer, crRNA, a T4 DNA ligase, an Fpg enzyme, a phi29 DNA polymerase and a Cas12a protein. The invention also provides a Ggt; the invention discloses an A mutation detection method and application. According to the invention, the Ggt based on the combination of the Fpg enzyme and CRISPR / Cas12a is successfully constructed; according to the universal detection method for the A mutation, a 8-oxoG modified lock-type probe is used for recognizing a mutation site, and rolling circle amplification and CRISPR / Cas12a cascade signal amplification system are combined, so that the core bottlenecks of insufficient universality caused by restriction enzyme dependence and strict dependence of Cas protein on a target PAM site in the existing mutation detection technology are solved in a breakthrough manner, and the purpose of detecting all Ggt, Ggt, Ggt, Ggt, Ggt, Ggt, Ggt, Ggt, Ggt, Ggt and Ggt mutation is achieved. And broad-spectrum and accurate detection of point A mutation is realized.

The present application relates to a kind of detection methods of strong putrefaction Pseudomonas lundensis, comprising extracting nucleic acid in the sample to be measured;Then with nucleic acid as template, using specific RAA primer pair is recombined enzyme-mediated amplification, and obtains amplification product;RAA primer pair targets the aprX gene of Pseudomonas lundensis comprising single nucleotide polymorphism site associated with strong putrefaction phenotype;Finally, the amplification product is added to CRISPR / Cas detection system, incubated at constant temperature, then real-time detects its fluorescence signal;Detection system includes Cas protein, specific crRNA and fluorescent reporter probe, and crRNA can recognize single nucleotide polymorphism site associated with strong putrefaction phenotype in Pseudomonas lundensis aprX gene.The present application improves the detection accuracy, and detection process is simple to operate, and reaction system is simple, not only improves detection efficiency, also reduces detection cost.

The embodiment of the invention provides a polymer probe, a preparation method and application thereof, and a detection kit. The polymer probe comprises a pre-amplifier and a post-amplifier, the pre-amplifier comprises streptavidin and a nucleic acid sequence, and the streptavidin and the nucleic acid sequence are coupled; the post-amplifier comprises branched chain DNA and a plurality of fluorescent probe sequences, each branched chain DNA comprises a plurality of binding sites, the binding sites and the fluorescent probe sequences are complementarily paired in base, and the tail end of each fluorescent probe sequence comprises a fluorescent reporter group; and a plurality of post-amplifiers are paired on each pre-amplifier in a base complementary manner. The polymer probe provided by the invention has high luminous intensity, can provide enough signal intensity in low-concentration target molecule detection, and can well detect low-concentration biotin markers when being applied to detection or used for a detection kit.

The invention relates to the technical field of biological detection, in particular to a CRISPR-Ca12a system based on an AND disordered logic gate and a preparation method and application of the CRISPR-Ca12a system based on the AND disordered logic gate. According to the system, gold nanoparticles serve as a carrier, closed DNAzyme and closed crRNA are fixed to the surface of the carrier of the gold nanoparticles through Au-S bonds on the surface of the carrier of the gold nanoparticles, and APE1 specific cleavage AP sites are designed on closed crRNA chains. Only when miRNA-141 and APE1 exist at the same time, active crRNA can be completely released through a cascade reaction, then the active crRNA is combined with Cas12a protein, the trans-cleavage activity of CRISPR-Ca12a is activated, and a signal is generated by a cleavage fluorescence report probe. The logic gate has disorder, that is, the trigger sequence of the two targets does not affect the final output. According to the invention, the reaction efficiency is improved by utilizing the space confinement effect of the gold nanoparticles, high-sensitivity and high-specificity collaborative detection of the double biomarkers is realized, the gold nanoparticles are successfully applied to precise fluorescence imaging of tumor cells, and a new strategy is provided for disease diagnosis.

The invention discloses a micromolecular fluorescent probe for specific imaging autophagy and a preparation method and application thereof, the fluorescent probe comprises a fluorophore, a linking group and an autophagy targeting group, the fluorophore is an intelligent fluorescence reporter group, the linking group adopts cysteine as a linking unit, and the autophagy targeting group targets LC3 protein; the probe can be used for specifically imaging an autophagy process of a biological sample and screening an autophagy regulator. The micromolecular fluorescent probe has the advantages of being good in cell membrane permeability, simple and convenient in dyeing process and easy to be compatible with other fluorescence labeling technologies, can perform specific recognition and selective imaging on an autophagy related structure, improves the targeting property and imaging credibility of the probe in a complex cell environment, and can be used for detecting autophagy related structures. The method can be used for visual tracing and detection of autophagy flow in living cells under physiological and pathological conditions, and is beneficial for promoting a small-molecule fluorescent probe to analyze an autophagy regulation mechanism and biological functions in real time.