11 results about "Dna sensor" patented technology

The application provides a DNA sensor based on gold nanoparticles (AuNPs) for visual detection of miRNA-10b. The sensor is obtained by coupling AuNPs-S1 through mercapto between gold nanoparticles (AuNPs) and probe S1; and coupling AuNPs-S2 through mercapto between gold nanoparticles (AuNPs) and probe S2. The combination of the probe and the gold nanoparticles is more firm due to mercapto modification, so that the stability and detection repeatability of the DNA sensor are improved. The aggregation of AuNPs is triggered by hybridization between the target miRNA-10b and the probe, the transition of AuNPs from dispersion to aggregation in the buffer solution is regulated, and the color change from red to blue is visible to the naked eye, so that the rapid and visual detection of the tumor marker miRNA-10b is realized. The linear range is 10 pM-200 nM, and the sensor has excellent stability in serum environments (1%, 10%) and enzymatic environments (5 U / mL DNase and 2 U / mL DNase), and high selectivity. An efficient tool is provided for cancer diagnosis.

This invention discloses a method for studying the mechanism by which the mucoprotein channel 1 (TRPML1) regulates the outflow of zinc ions from lysosomes and induces changes in mitochondrial ATP. This method uses 13 nm AuNPs as loading materials to construct a logic-gated sensor for pH and zinc ion regulation within lysosomes and for TRPML1 mRNA in the cytoplasm. It also uses 5 nm AuNPs as loading materials to construct a sensor targeting mitochondrial ATP for cell imaging. This method enables the detection of mRNA and zinc ions in the cytoplasm, lysosomes, and mitochondria. 2+ ATP-associated ATP sensors, Zn 2+ Three sensors—a sensor, an mRNA sensor, and an X-ray sensor—are used simultaneously to image cells, aiming to answer questions about the mechanisms of ATP changes in mitochondria under the regulation of zinc ion efflux from lysosomes by TRPML1.

The invention relates to the technical field of detection, and discloses a preparation method of a photoelectrochemical DNA sensor and application of the photoelectrochemical DNA sensor in leather cultural relic detection. The method comprises the following steps: (1) preparing a T-COF / Ag2S heterojunction dispersion liquid; (2) preparing a PAMAM (at) DNA probe solution; (3) preparing a dispersion liquid of TiO2 (at) NH2-MIL-125 (Ti); and (4) assembling the sensor. The photoelectrochemical DNA sensor disclosed by the invention has relatively high response specificity, does not cause excessive damage to the cultural relics, is good in portability and can be used for on-site rapid detection of the leather cultural relics.

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

The invention discloses a method for preparing a graphene nanobelt-DNA sensor based on a template method and a method for detecting mercury ions, and the method for preparing the graphene nanobelt-DNA sensor based on the template method comprises the following steps: S1, preparing a graphene substrate; s2, positioning and fixing a template; s3, oxygen plasma etching and template removal are carried out; s4, carrying out electrode evaporation; s5, activating the sensor and connecting with the DNA; the graphene nanobelt is prepared by adopting a template method, a silicon nanowire or a carbon nanotube is selected as a template, an oxygen plasma etching technology is combined, the morphology and size of the graphene nanobelt can be accurately controlled, a large number of carboxyl groups are introduced into the edge of the etched graphene nanobelt, and sufficient active sites are provided for subsequent stable connection with DNA (Deoxyribose Nucleic Acid); meanwhile, by optimizing the concentration ratio of the EDC / NHS activating agent, the DNA concentration and the reaction temperature, the connection efficiency of the graphene nanobelt and the DNA is remarkably improved, and the electrical stability of the sensor is ensured.

This invention discloses an electrochemical gene sensor based on Ti3C2@AuNP, its preparation, and its application, belonging to the field of biosensing technology. The Ti3C2@AuNP-based electrochemical DNA sensor of this invention is prepared by drop-coating Ti3C2@AuNP onto the surface of a working electrode, followed by self-assembly of a methylene blue-labeled and thiol-modified hairpin HP-Sul2 probe onto the electrode surface, thus creating a ratiometric electrochemical DNA sensor capable of detecting the Sul2 antibiotic resistance gene. This sensor has advantages such as simple preparation process, low cost, high sensitivity, good reproducibility, and storage stability, providing a powerful tool for the sensitive and specific detection of antibiotic resistance genes in aquatic environments.

The present invention provides an anti-pollution photoelectrochemical DNA sensor constructed based on a polypeptide-hairpin DNA conjugate, which relates to the technical field of HIV detection. The detection process of the anti-pollution photoelectrochemical DNA sensor includes the preparation of a PDA / TCPP / COF-V photoanode, the preparation of a conjugate LZP-hDNA, the preparation of a nucleic acid probe pDNA-AgInS2, the construction of an anti-pollution DNA sensor, and photoelectrochemical testing. The present invention uses a click reaction to react a linear zwitterionic peptide LZP modified with an -N3 azide group and a hairpin DNA (hDNA) modified with 3'-dibenzocyclooctyne (DBCO) to form an LZP-hDNA conjugate. This conjugate not only has an anti-pollution effect, but the presence of hDNA also facilitates the progress of the λ-Exo-assisted target recycling amplification reaction. By modifying a composite material of meso-tetrakis(4-carboxyphenyl)porphyrin (TCPP) and polydopamine (PDA) on a COF-V electrode, a ternary composite photoanode of PDA / TCPP / COF-V is prepared, which serves as a signal transducer for the sensing platform and firmly anchors the LZP-hDNA conjugate.

The invention relates to a self-assembled three-dimensional ball-flower type bimodal DNA sensor based on a rolling ring amplification technology, which is used for detecting target DNA of microorganisms in an early fouling stage. The sensor consists of a lock ring probe, target DNA (Deoxyribose Nucleic Acid) and a fluorescent nanogold probe. When the target DNA exists, the locked loop probe specifically recognizes the target DNA, rolling circle amplification is carried out under the action of T4DNA ligase and phi29 DNA polymerase, and a stable nano flower ball structure is formed through self-assembly. One end of the fluorescent signal probe modifies the fluorescent nanogold, and the other end of the fluorescent signal probe is complementary with a rolling circle amplification product to form a complete sensor after combination. The fluorescence spectrophotometer is used for measuring a fluorescence signal, the intensity of the fluorescence signal is positively correlated with the concentration of the target DNA, and qualitative and quantitative detection of the target DNA is realized. The nanometer flower ball structure enables a fluorescence signal to be enhanced and a color signal to be weakened, and self-calibration is achieved through comparison of the fluorescence signal and the color signal. The specific sequence of the sulfate reducing bacteria is taken as the target gene, so that the kit has high selectivity and anti-interference capability, and is suitable for rapid detection of early-stage fouling microorganisms.

The invention provides an optical fiber DNA sensor prepared by combining a molybdenum disulfide material and a detection method, a micro-fluidic chip with a tip coupled bubble structure is provided, the micro-fluidic chip comprises an elastic material chip and a glass sheet which are bonded, the plane of the glass sheet covers the plane projection part of the elastic material chip, and the plane projection part of the elastic material chip covers the plane projection part of the glass sheet. One plane of the elastic material chip is used as a bonding plane to be bonded with the glass sheet, a groove penetrating through the length direction of the elastic material chip is formed in the bonding plane, and the groove is used for placing the optical fiber biosensor in the length direction and is filled with liquid acting on the optical fiber biosensor; the groove comprises a liquid channel, a first extension area, a second extension area and a plurality of tip coupling bubble structures, the first extension area and the second extension area are located on the two sides of the liquid channel in the length direction respectively, and the tip coupling bubble structures are located on one side of the liquid channel in the width direction.

The application belongs to the technical field of nucleic acid detection, and specifically discloses a lanthanide metal organic framework DNA sensor as well as a preparation method and application thereof. The lanthanide metal organic framework (LaMOF) surface is not fully coordinated with metal sites, and the chemical coordination reaction activity of the oligonucleotide phosphate group is utilized. A capture DNA strand complementary to a target DNA is coupled to the LaMOF surface to construct a fluorescence biosensor based on the LaMOF. The synthesis steps are simple, complex synthesis reactions are avoided, the solvent is non-toxic and environmentally friendly, the operation is simple, and the time cost and reagent cost are low. Then, the luminescent metal organic framework and the in-situ fluorescence quenching reaction are combined to detect nucleic acids, the amount of the target DNA is specifically converted into a fluorescence signal, and quantitative analysis of free nucleic acid cfDNA is realized. The method has a good linear correlation in a concentration range of 25-250 nM, is high in precision, and is good in reproducibility.

The present invention discloses a kind of high-efficiency electrochemical DNA sensor and its preparation and application, belong to the field of electrochemical biosensor technology, by introducing freeze-thaw technology, effectively accelerates the molecular motion and collision frequency during HCR process, thereby significantly shortening the reaction time, so that the whole detection process can be completed within 30 minutes, target miR-21 is combined with capture probe to trigger HCR process, generate long-chain DNA polymer and greatly amplify the detection signal, introduce methylene blue as electrochemical label, utilize its redox reaction on electrode surface to produce measurable electrical signal, realize rapid and sensitive quantitative detection of miR-21. The method shows excellent linearity and sensitivity in the extremely low concentration range of 1×10-9M~2.5×10-14M, with a detection limit as low as 1.0×10-14M, easy to operate, good reproducibility, and provides a new approach for the clinical detection of miR-21, with broad application prospects.