79 results about "DNA Aptamers" patented technology

The invention discloses a preparation method and application of a chlorogenic acid carbon quantum dot microsphere capsule, a natural active product chlorogenic acid (CHA) in coffee is used as a raw material, and chlorogenic acid carbon quantum dots (CHA CDs) with anti-inflammatory and antioxidant activity are synthesized through a hydration method; then, the chlorogenic acid carbon quantum dots (CHACDs) are packaged with chitosan, and meanwhile, the chitosan on the outer layer of the capsule is modified with the DNA aptamer, so that the chlorogenic acid carbon quantum dot microsphere capsule Apt-CS (at) CHA CDs are obtained. The chlorogenic acid carbon quantum dot microsphere capsule disclosed by the invention not only has anti-inflammatory and antioxidant activity, but also can regulate intestinal flora, enhance intestinal barrier function and immune conditions; moreover, the microsphere capsule can be retained in the intestinal tract for a long time, so that the microsphere capsule can resist inflammation and remove high-level reactive oxygen species (ROS), can be retained in the intestinal tract for a long time and play a role in regulating intestinal flora, finally, the disease development of IBS is comprehensively relieved, and the microsphere capsule has a very good application prospect.

The invention relates to the technical field of biological medicines, in particular to a preparation method of an inhibitor targeting a MAX-PD-L1 promoter specific binding motif and a double-target inhibitor, through ChIP-seq and site-directed mutagenesis experiments, a core binding motif of MAX and a PD-L1 promoter, such as 5 '-CAC [GA] TG-3', is defined, it is ensured that the inhibitor only targets a key site of MAX-PD-L1 interaction, and the activity of the MAX-PD-L1 promoter specific binding motif is improved. The off-target effect is avoided, and a high-specificity target spot is provided for subsequent inhibitor design. The cell permeability of the DNA aptamer screened based on the specific binding motif is improved after cholesterol modification, and the affinity of the DNA aptamer is obviously higher than that of a traditional antibody. A small molecule compound virtually screened through a molecular docking model is optimized through hydrogen bond and hydrophobic interaction, and then the binding affinity with MAX is improved. After treatment with the inhibitor, the combination inhibition rate of MAX and the PD-L1 promoter is high, the transcriptional activity of PD-L1 is obviously reduced, the killing rate of T cells to tumor cells is also improved, and immune escape is effectively blocked.

The application belongs to the field of chemical biology, and relates to a Fusobacterium nucleatum single-stranded DNA aptamer and a screening method and kit. The nucleotide sequence of the aptamer is as follows: 5'-TGACTGACGACGACTCCGCX1GX2X3X4GX5AGX6X7X8X9X 10 CGTX 11 X 12 X 13 X 14 X 15 X 16 X 17 X 18 X 19 X 20 X 21 X 22 X 23 GX 24 X 25 X26X 27 X 28 AX 29 X 30 GX 31 X 32 X 33 X 34 X 35 X 36 AGACTGCTCGAGCTG-3'. The aptamer obtained by the application has the characteristics of simple operation, high sensitivity, low manufacturing cost and strong specificity, and has a broad application prospect in the detection of Fusobacterium nucleatum.

The present invention relates to a single-stranded DNA aptamer that binds to glutathione to inhibit oxidation of the glutathione or stabilize the glutathione, characterized in that the single-stranded DNA aptamer has one or more stem-loop structures; a method for oxidation prevention and stabilization of glutathione using the aptamer; and application to various fields such as pharmaceuticals, cosmetics, and food, using the aptamer. The aptamer of the present invention can be applied to various fields, such as pharmaceuticals, cosmetics, and food, which require oxidation prevention and stabilization of glutathione.

Disclosed are DNA aptamers. Related compositions and kits are also provided. Also disclosed are methods for amplifying a target DNA sequence using the DNA aptamers, and methods of identifying the DNA aptamers.

Disclosed are DNA aptamers. Related compositions and kits are also provided. Also disclosed are methods for amplifying a target DNA sequence using the DNA aptamers, and methods of identifying the DNA aptamers.

The present invention addresses the problem of providing a novel method for efficiently producing an aptamer having a high affinity for a target substance. Provided is a single-stranded nucleic acid molecule library comprising a plurality of single-stranded nucleic acid molecules, the multiple single-stranded nucleic acid molecules comprise a single-stranded nucleic acid molecule containing Ds / Pa ', and the single-stranded nucleic acid molecule containing Ds / Pa' comprises a pair of primer binding regions located at the 5'terminal and the 3 'terminal of the single-stranded nucleic acid molecule and a variable region located between the pair of primer binding regions. The pair of primer binding regions is composed of a base sequence shared among the plurality of single-stranded nucleic acid molecules, and the variable region comprises a non-natural base Ds (7-(2-thienyl)-3H-imidazo [4, 5-b] pyridine-3-yl) represented by general formula (I) and a non-natural base Pa'represented by general formula (II).

Provided are DNA aptamers selected from a DNA library using Cell-SELEX to bind specifically to cancer cells, which are optimized for high binding affinity to cancer cells can be effectively used for the diagnosis of cancer as they have enhanced targeting efficiencies for target cells and tissues as well as high serum stability.

The invention discloses a label-free ratio fluorescence sensor and a method for detecting fentanyl substances, and belongs to the field of analysis and detection.The sensor comprises a recognition element, the recognition element comprises six kinds of guanine-rich DNA aptamers and a signal conversion element, and the signal conversion element comprises a fluorescent dye. According to the invention, a plurality of fentanyl analogues can be rapidly detected.

The invention discloses a chimeric antigen receptor targeting EGFRvIII and application of the chimeric antigen receptor. The chimeric antigen receptor sequentially comprises an EGFRvIII targeting nucleic acid aptamer, a transmembrane domain and an intracellular signal domain from an N end to a C end, the EGFRvIII targeted nucleic acid aptamer is an EGFRvIII specific DNA aptamer obtained on the basis of SELEX (systematic evolution of ligands by exponential enrichment) screening, can only be combined with an extracellular domain of the EGFRvIII, and is not combined with an EGFR (epidermal growth factor receptor) wild type; the intracellular signal domain comprises a costimulatory signal domain and an activation signal domain, the C end of the costimulatory signal domain is connected with the N end of the activation signal domain, and the EGFRvIII specific nucleic acid aptamer screened based on SELEX is adopted as a targeting domain, can only be specifically combined with the extracellular domain of EGFRvIII positive tumor cells, and is not subjected to cross combination with EGFR wild cells and normal cells, so that the EGFRvIII specific nucleic acid aptamer can be used for detecting EGFRvIII positive tumor cells, and the EGFRvIII specific nucleic acid aptamer can be used for detecting EGFRvIII positive tumor cells. The problem of off-target killing caused by the fact that a common antibody scFv fragment of a traditional chimeric antigen receptor (CAR) is easily combined with a wild type EGFR is fundamentally avoided.

The application belongs to the technical field of electrochemiluminescence detection, and discloses a preparation method of a thiamethoxam electrochemiluminescence sensor based on Fe / Zn-MOF@C-dots sensitization, which comprises the following steps: C-dots preparation, Fe / Zn-MOF preparation, Fe / Zn-MOF@C-dots preparation, modification of Fe / Zn-MOF@C-dots to the surface of a glassy carbon electrode through chitosan, then combination of a single strand of thiamethoxam DNA aptamer to the surface of the composite nanomaterial as a recognition element through a crosslinking agent, construction of a biosensor capable of recognizing thiamethoxam, electrochemical method detection and electrochemiluminescence method detection. The Fe / Zn-MOF@C-dots composite material is used as an electrochemiluminescence reagent for the first time, and compared with C-dots, the electrochemiluminescence signal of the Fe / Zn-MOF@C-dots is significantly enhanced; at the same time, the sensor uses DNA aptamer as a specific recognition element of the target molecule thiamethoxam, and effectively improves the selection performance of the sensor. The sensor shows significant repeatability, good selectivity and long-term stability, and can be used as an effective means for detecting thiamethoxam residues in agricultural products and origin environments.

The application provides a SETDB1 aptamer, a PROTAC constructed based on the aptamer and application, and relates to the technical field of biological medicines.The nucleotide sequence of the SETDB1 aptamer is any one of SEQ ID NO.1 or SEQ ID NO.2.Through SELEX screening, a DNA aptamer targeting SETDB1 is identified, and the DNA aptamer is specifically combined with a Tudor domain; based on the screened SETDB1 aptamer, a first PROTAC of SETDB1 is constructed.Single-chain PROTAC and double-chain PROTAC are synthesized, and the above-mentioned PROTACs are all targeted to degrade SETDB1 in tumors, and have no effect on non-tumor cells or tissues.

The invention belongs to the field of aquatic bacteria detection, and relates to a fluorescent array sensor as well as a preparation method and application thereof. The fluorescent array sensor comprises a plurality of DNA aptamers, the DNA aptamers respectively target lipopolysaccharide, peptidoglycan and flagellin, the DNA aptamers of the target lipopolysaccharide are EA5 and LA27, the DNA aptamer of the target peptidoglycan is Antibac2, and the DNA aptamer of the target flagellin is Aptamer 3; the sequence of the EA5 is shown as SEQ ID NO.1, the sequence of the LA27 is shown as SEQ ID NO.2, the sequence of the Antibac2 is shown as SEQ ID NO.3, and the sequence of the Aptamer 3 is shown as SEQ ID NO.4. The invention further discloses a kit for detecting the content of the EA5, the LA27, the Antibac2 and the Aptamer. According to the present invention, the six bacteria can be simultaneously detected, the detection limit is low, the operation process is simple, and the detection accuracy can achieve 97.6%.

The present invention relates to a DNA aptamer specifically binding to an alpha-synuclein protein and uses thereof. Specifically, the present invention relates to a DNA aptamer selected from the group consisting of nucleotide sequences of SEQ ID NOS: 1 to 12 and binding specifically to an α-synuclein protein, and a composition for detecting an α-synuclein protein, a detection kit, a detection chip or a microarray, all comprising the aptamer as an active ingredient. In addition, the present invention relates to a method for detecting an α-synuclein protein, a method for providing information for diagnosing a degenerative brain disease, a composition for diagnosing a degenerative brain disease, and a pharmaceutical composition for preventing or treating a neurodegenerative disease, all using the DNA aptamer of the present invention.

The application discloses a one-step monoclonal antibody drug electrochemical detection biosensor and a preparation method and application thereof. The application designs and screens an affinity specific DNA aptamer hairpin probe and uses the same as a specific capture unit, then uses a gold-sulfur bond to fix the DNA aptamer hairpin probe on a screen-printed electrode surface, meanwhile, uses a self-assembly interaction between a metal and a mercapto group to fix a blocking agent introduced on the screen-printed electrode surface, and blocks the excess electrode surface reaction sites, so that the one-step monoclonal antibody drug electrochemical detection biosensor is obtained. The one-step monoclonal antibody drug electrochemical detection biosensor has the advantages of simple operation, high sensitivity, less non-specific adsorption, high capture efficiency, stable physical and chemical properties, strong specificity and good selectivity, and can be used for capturing antibody drugs in complex biological samples.

The present disclosure relates to aptamers that specifically bind to Cytokeratin 8 (CK8) and / or Cytokeratin 18 (CK18) and their use as biomarkers for the detection of cancer, preferably carcinoma or adenocarcinoma. The present disclosure also relates to an intraoperative surgical pathology method that provides for the rapid identification of cancer cells, in particular carcinoma or adenocarcinoma, in a biological sample.

The application relates to the technical field of nanomaterials, in particular to an EpCAM aptamer modified nanomaterial and a preparation method and application thereof, wherein the nanomaterial takes carboxylated mesoporous silica nanoparticles as a carrier, and an EpCAM specific DNA aptamer is covalently coupled to the surface of the nanomaterial; the sequence of the EpCAM specific DNA aptamer is shown as SEQ ID No. 1. The nanomaterial can specifically capture tumor-derived exosomes (EVs) in blood, and can realize sensitive detection of EVs in the 7-day (early stage) and 21-day (late stage) stages of an HT29 colon cancer model and the 7-day stage of an A549 / H460 lung cancer model, thereby providing a minimally invasive liquid biopsy new tool for early diagnosis of colon cancer and lung cancer, and solving the inherent limitation problems of sensitivity and specificity of existing diagnosis means in cancer detection.

The present invention relates to the field of molecular biology, and more particularly to nucleic acid aptamers, derivatives, and applications thereof for detecting TSHR protein. The present invention provides a nucleic acid aptamer for detecting TSHR protein, the nucleotide sequence of which is shown in SEQ NO. 1. The present invention provides a DNA aptamer YC6 with high affinity for TSHR protein, which has been validated at the molecular, cellular, and tissue levels. The present invention discovers that the DNA aptamer YC6 has the ability to recognize and target cells expressing thyrotropin receptors, providing new insights into the diagnosis and treatment of thyroid diseases and thyroid-related eye diseases.

The invention belongs to the technical field of biology, and particularly relates to a DNA aptamer for improving CRISPR / Cas9 mediated exogenous gene integration efficiency based on CtIP protein and application of the DNA aptamer, and the nucleotide sequence of the DNA aptamer is as shown in at least one of SEQ ID NO.1 and SEQ ID NO.10. The invention further discloses a preparation method of the DNA aptamer for improving CRISPR / Cas9 mediated exogenous gene integration efficiency based on CtIP protein. According to the invention, the key factor CtIP protein in DNA double-strand breakage repair is taken as a target for the first time, two aptamers are screened, and the donor vector of a CRISPR / Cas9 system is optimized by utilizing the aptamers, so that the integration efficiency of exogenous genes in HEK-293T cells and Hela cells is improved. The affinity of the CtIP protein specific DNA aptamer obtained through screening reaches the nanomole level, and the Kd value ranges from 42.56 nM to 407.29 nM. An aptamer is inserted into the tail end of a homologous arm of a donor carrier, and directional enrichment of a repair template is realized by utilizing an HMEJ mechanism. The aptamer A6913 and / or A13-32 significantly improves the integration efficiency of the exogenous gene, and the integration efficiency is improved by more than 3 times compared with a control group.

The present invention provides immunostimulatory nucleic acids that have an affinity to a specific target protein. The present invention also provides templates and methods for making and using the immunostimulatory nucleic acids. Further, methods for linking the immunostimulatory nucleic acids to antigens and using the resulting complexes to enhance an immune response are provided.

The invention relates to a positively charged peptide capable of non-covalently interact with negatively charged extracellular vesicles or nanoparticles. Said peptide is a fragment of the bacterial protein P40 and shows better interaction capabilities that the entire bacterial protein P40. The peptide of the invention can also be linked to a targeting element, such as targeting peptide, DNA aptamer, RNA aptamer, a protein, an antibody or a fragment thereof that binds to a target molecule, therefore it can be used for the targeted delivery of extracellular vesicles or nanoparticles further comprising a bioactive agent to a target cell, tissue or particle like a virus, that comprise the target molecule. Therefore, the present invention also relates to a carrier complex comprising the peptide of the invention non covalently bound to an extracellular vesicle or nanoparticle comprising a bioactive agent and its uses.

Disclosed herein is the use of DNA aptamer assemblies of varying DNA length, structure, and sequence to both bind to collagen and other proteins, to then act as a biocompatible, degradable, reversible, or permanent 3D crosslinkers between proteins, and to service as a biologically functional material when using the appropriate aptamer sequence. Therefore, disclosed herein are compositions comprising collagen fibers crosslinked with DNA aptamers. Also disclosed are devices and implants made from or coated with collagen fibers crosslinked with DNA aptamers. Also disclosed are methods of making collagen fibers. Also disclosed are kits for producing collagen fibers. Also disclosed herein are compositions DNA aptamers in a collagen fiber matrix that stabilizes the DNA aptamer.

The invention discloses a multi-hot-spot wearable dopamine detection SERS sensor and a preparation method and application thereof.The sensor comprises a hydrogel substrate and an SERS chip loaded on the surface of the hydrogel substrate, the SERS chip comprises a solid PDMS substrate and a double-layer sandwich structure anchored through DNA hybridization, one single layer is of a multi-hot-spot structure, and the other single layer is of a multi-hot-spot structure. One single layer is a hydrophilic superlattice gold film which is an ordered array composed of double-layer gold and silver hollow nanoparticles modified with signal molecules and dopamine DNA aptamer chain segments, the thickness of the ordered array is 20-50 nm, the other single layer is a hydrophilic superlattice gold film composed of gold nanoparticles modified with dopamine DNA complementary chain segments, the thickness of the hydrophilic superlattice gold film is 15-50 nm, and the thickness of the hydrophilic superlattice gold film is 20-50 nm. The hydrophilic superlattice gold film modified with the dopamine DNA complementary chain segment is in direct contact with the solid PDMS substrate, and the solid PDMS substrate is in direct contact with the hydrogel substrate. According to the invention, high-sensitivity and high-stability detection of dopamine in sweat can be realized, and the device is convenient to wear.

The application discloses a DNA aptamer binding to LOX-1 protein and application thereof. Specifically, the application provides a DNA aptamer binding to LOX-1 protein, wherein a core sequence of the DNA aptamer binding to the LOX-1 protein comprises a sequence as shown in SEQ ID NO: 5. The aptamer has small molecular weight, stable chemical property, is easy to preserve and label, can be combined with the LOX-1 protein through space conformation matching, accumulation of bases in a sequence, electrostatic interaction between charged groups or hydrogen bond interaction, and the like, has high affinity and good specificity.

The invention relates to the technical field of analytical chemistry, and particularly discloses a double-signal reverse change ratio type up-conversion nanoprobe for lead ion detection as well as a preparation method and application of the double-signal reverse change ratio type up-conversion nanoprobe. The double-signal reverse change ratio type up-conversion nanoprobe for lead ion detection comprises an up-conversion nanoparticle coated with polyacrylic acid and a DNA (Deoxyribose Nucleic Acid) aptamer modified by Cy3, wherein the Cy3 modified DNA aptamer is used as a specific recognition unit of Pb < 2 + >, the Cy3 is used as an energy receptor, and the polyacrylic acid coated up-conversion nanoparticles are used as an energy donor. According to the double-signal reverse change ratio type up-conversion nanoprobe, the DNA aptamer is induced to generate conformational change through specific binding of the DNA aptamer and Pb < 2 + >, the distance between up-conversion nanoparticles and Cy3 is shortened, and a ratio type detection signal is constructed through quenching of an emission peak of the up-conversion nanoparticles at 540 nm and enhancement of an emission peak of Cy3 at 565 nm; finally, high-sensitivity and high-selectivity detection on trace Pb < 2 + > is realized, and the detection sensitivity is improved.

The present disclosure relates to novel DNA aptamers and use thereof. In particular, the present disclosure relates to DNA aptamers selected from a DNA library using Cell-SELEX to bind specifically to cancer cells. The DNA aptamers of the present disclosure selected and optimized for high binding affinity to cancer cells can be effectively used for the diagnosis of cancer as they have enhanced targeting efficiencies for target cells and tissues.

The application belongs to the field of biomedical detection, and relates to a multi-modal nano probe NETs detection kit, a preparation method thereof and a NETs concentration detection method. The multi-modal nano probe NETs detection kit comprises a nano probe and a chemiluminescence working solution. The nano probe comprises a gold nano star, a histone H3 antibody-glucose oxidase conjugate fixed on the surface of the gold nano star, an MPO antibody-horseradish peroxidase conjugate and a double-stranded DNA aptamer-alkaline phosphatase conjugate. The chemiluminescence working solution is a Tris-HCl buffer solution containing glucose, luminol, p-nitrophenyl phosphate and an enhancer. In the application, after the nano probe is combined with NETs, the addition of the chemiluminescence working solution can form an efficient signal amplification network, the detection sensitivity of the kit to NETs can reach 0.02 nM, and low-concentration NETs of early inflammatory patients can be accurately detected.

The invention discloses a DNA (Deoxyribose Nucleic Acid) aptamer for targeting nucleolin and application of the DNA aptamer, belongs to the technical field of oligonucleotides, and particularly relates to the DNA aptamer for targeting nucleolin. The DNA nucleic acid aptamer is obtained by reacting AS1411 of which the 5'end is modified by amino and a triptolide derivative; the triptolide derivative is obtained by modifying triptolide with a vinyl carboxylic acid derivative; the vinyl carboxylic acid derivative is prepared by the following preparation steps: under the action of a catalyst, allyl succinic anhydride firstly reacts with 4-(chloromethyl) benzyl alcohol, and then reacts with sodium bicarbonate to obtain the vinyl carboxylic acid derivative. The DNA aptamer for targeting nucleolin disclosed by the invention not only can be efficiently combined with nucleolin, but also has good effects of inhibiting tumor cell proliferation and inhibiting tumor growth.

The application discloses a non-natural base DNA aptamer targeting Bacillus cereus 5 / B / 6 metal beta-lactamase and a screening method thereof. The screening method uses dNaMTP and dTPT3TP, or dCNMOTP and dTPT3TP as non-natural base nucleoside triphosphate substrates, uses OneTaq DNA polymerase to amplify a DNA library containing non-natural bases, and uses lamda exonuclease to degrade 5' end phosphorylated DNA chains in PCR products, so as to obtain two ssDNA libraries. The non-natural base DNA aptamer targeting Bacillus cereus 5 / B / 6 metal beta-lactamase is screened based on the libraries, and three non-natural base DNA aptamers with a length of 70 nt are obtained. The results of a biological membrane layer interference analysis show that the three non-natural base DNA aptamers have good binding affinity to Bacillus cereus 5 / B / 6 metal beta-lactamase.

The invention relates to the technical field of biological medicine and food safety, and discloses a preparation method of an aflatoxin B1 adsorbent, which comprises the following steps: co-incubating animal cell suspension treated by benzenesulfonyl fluoride, a photoinitiator and a gel monomer, collecting cell particles by low-speed centrifugation, and removing redundant photoinitiator and gel monomer to obtain an aflatoxin B1 adsorbent; irradiating by a 365 nm ultraviolet lamp to prepare gelatinized cell particles; and co-incubating the prepared gelated cell suspension and a cationic polymer solution, carrying out low-speed centrifugation to remove redundant polymer, and co-incubating the DNA aptamer and the treated gelated cells to finally obtain the DNA aptamer-loaded gelated cell particles (DNA-GC). The DNA-GC adsorbent prepared by the invention shows extremely high affinity and selectivity to aflatoxin B1 (AFB1), and can be used for accurately identifying and capturing AFB1 molecules in a complex biological medium.