124 results about "Electrochemical biosensor" patented technology

The invention provides an electrochemical biosensor based on ultrasonic bidirectional driving and a detection method, and belongs to the technical field of biosensing. The sensor comprises a porous membrane and an ultrasonic bidirectional driving unit, and a probe capable of specifically capturing a target object is fixed in a pore channel of the porous membrane; the ultrasonic bidirectional driving unit is composed of a first ultrasonic transducer and a second ultrasonic transducer which are symmetrically arranged on the two sides of the porous membrane, and can synchronously execute reverse power gradient change to form alternately changing pressure difference on the two sides of the membrane so as to drive liquid to repeatedly penetrate through the porous membrane. The detection method comprises the steps of to-be-detected liquid injection and ultrasonic bidirectional driving, ultrasonic auxiliary cleaning and electrochemical detection. The problems of insufficient probe utilization rate, low mass transfer efficiency and non-specific adsorption of a traditional passive diffusion mechanism are solved by utilizing bidirectional ultrasonic active driving force, the detection sensitivity, speed and signal-to-noise ratio are remarkably improved, and the method is suitable for rapid and high-sensitivity quantitative analysis of various analytes.

The invention discloses an electrochemical biosensor of a light-driven nanopore channel and application of the electrochemical biosensor. According to the sensor, a photoresponse nanopore membrane is constructed, an outer surface aptamer probe is combined, asymmetric photothermal gradient driven ion transmission induced by near-infrared light is utilized, and ultra-sensitive detection on a target object is realized by regulating and controlling the charge density of the outer surface. According to the electrochemical biosensor provided by the invention, traditional voltage driving is replaced by asymmetric near-infrared light driving, so that the electrochemical biosensor has a relatively wide detection range and an extremely low detection limit, and high-sensitivity and specific detection on a target object can be realized. The electrochemical biosensor can be used for detecting microcystin-LR (MC-LR), the detection limit reaches 1 * 10 <-7 > mu g / L, the sensitivity is improved by 5 orders of magnitude compared with that of a traditional voltage-driven sensor, and the electrochemical biosensor can be applied to trace pollutant detection in the fields of environmental monitoring, food safety and the like.

The invention discloses an electrochemical biosensor for detecting mycobacterium tuberculosis. The sensor takes a porous membrane as a base material, the inner wall of a pore channel of the porous membrane is co-modified with a polydopamine (PDA) and conductive carbon material composite layer, and an amino-modified specific capture probe based on a mycobacterium tuberculosis ESAT-6 gene is fixed on a modification layer through covalent binding. When a target gene is captured by a probe, the volume effect of the target gene causes blockage of a porous channel of the porous membrane, so that electrochemical signals (such as current) of the sensor are changed, and high-sensitivity and specific detection of mycobacterium tuberculosis is realized. According to the invention, a porous structure, biological probe specific fixation and an electrochemical signal conversion technology are combined, and a novel efficient tool is provided for rapid diagnosis of tuberculosis.

This invention discloses an amplification-free electrochemical biosensor and method based on CRISPR-Cas13a. The sensor includes an electrochemical biosensor substrate, a dual-channel RNA reporter molecule, a CRISPR-Cas13a reaction system, and a dual-channel differential signal processing module. The working electrode surface is immobilized with a stem-loop structured first reporter molecule and a linear second reporter molecule loaded with gold nanoparticles, labeled with methylene blue and ferrocene signal molecules respectively, and immobilized with a ferrocene-specific capture probe. When target RNA is present, Cas13a is activated and non-specifically cleaves the reporter molecule, reducing the methylene blue signal and enriching and enhancing the ferrocene signal. Background self-calibration is achieved through dual-channel differential ratio calculation. This invention integrates signal attenuation and signal enhancement modes, offering advantages such as nucleic acid amplification-free operation, fast detection speed, high sensitivity, and strong anti-interference capability.

The invention discloses an aptamer electrochemical biosensor for estradiol detection as well as a preparation method and application of the aptamer electrochemical biosensor. The aptamer electrochemical biosensor is obtained by growing AuNPs particles on the surface of MoS2 to prepare a MoS2-AuNPs composite material, fixing the composite material on the surface of an electrode through chitosan, hybridizing aptamer probes P1 and P2, and self-assembling the aptamer probes P1 and P2 on the surface of the electrode through Au-S bonds. The sensor can be used for in-situ detection of hormone factor estradiol in sweat, can be applied to non-invasive monitoring equipment, and provides reliable and timely monitoring data.

The application belongs to the field of electrochemical biosensors, and more particularly relates to a protein molecule labeling method for constructing a high-performance electrochemical sensor. In the application, organic ligands on the surface of sulfide colloidal quantum dots are replaced with water-soluble ligands through liquid-phase ligand replacement, and then mixed with a carboxyl activator to activate the carboxyl groups of the water-soluble ligands, followed by uniform mixing with protein molecules, so that the protein molecules are effectively labeled on the quantum dots. The quantum dots prepared in the application, which have water-soluble ligands on the surface and are labeled with protein molecules, are coated on the working electrode of a planar three-electrode system through a one-step method, and after drying, an electrochemical biosensor with a wide detection range, high response sensitivity and strong anti-interference performance is prepared.

Described herein is a zwitterionic polymer-based coating that, when applied to an electrochemical biosensor, is capable of reducing fouling without compromising the current signal while also facilitating probe attachment.

The application provides an electrochemical sensing ELISA reagent card, comprising a microfluidic channel body and an electrochemical sensor body which are bonded together, wherein: a plurality of "annular" liquid flow channels are arranged on the microfluidic channel body, each "annular" liquid flow channel is formed by a working electrode covering flow channel and a counter electrode and a reference electrode covering flow channel in series, and the "annular" liquid flow channels are communicated through a common flow channel; the electrochemical sensor body comprises a flat plate substrate and a plurality of screen-printed electrodes which are printed in parallel on the flat plate substrate, and each screen-printed electrode comprises a working electrode, a counter electrode and a reference electrode. The electrochemical sensing ELISA reagent card combines an electrochemical biosensor and a microfluidic chip, and solves the technical problems of large sample / reagent consumption, single detection index and liquid volume influence on absorbance measurement of a traditional ELISA reagent kit.

The application discloses a paper-based electrode based on liquid metal assisted laser-induced graphene and a preparation method thereof, which comprises a substrate layer, a functional layer, a conductive layer and a hydrophobic layer arranged in sequence, the substrate layer is paper, the functional layer is formed by coating liquid metal nanoparticles, the conductive layer is an electrode formed by laser-induced graphene technology, and the hydrophobic layer is a fluid control area formed by wax packaging. The application combines liquid metal with laser-induced graphene technology, performs surface modification through eutectic gallium indium (EGaIn), polyimide (PI) and N-methyl pyrrolidone (NMP) composite slurry, and then forms a conductive electrode pattern on the paper-based surface by using laser-induced graphene (LIG) technology. The method has the advantages of simple preparation, low cost and environmental friendliness, and the prepared paper-based electrochemical biosensor has excellent conductive performance, mechanical flexibility and electrochemical activity.

This invention belongs to the field of electrochemical testing technology and discloses a dual-plate portable electrochemical testing system, including an upper plate, a lower plate, an electrochemical biosensor electrode converter, and a mobile terminal APP. The invention adopts an upper and lower plate structure, separating the data programming surface and the sensor interface surface, facilitating the replacement and upgrading of computing resources and the analog front-end separately. The invention hierarchically lays out the three-electrode interface analog circuit and the communication control circuit, and separates the power supply for digital and analog power supplies, which helps reduce mutual interference between the sensor's analog signal lines and digital communication signal lines, improving the stability of electrochemical testing. This invention enables wireless interaction via a mobile terminal and can be portablely powered by an external terminal device, offering flexible usage and facilitating on-site deployment and mobile testing. This invention supports multiple testing modes, including cyclic voltammetry, chronoamperometry, and differential pulse voltammetry, adapting to different electrochemical testing needs.

The application relates to the technical field of electrochemical detection, in particular to a micro-needle electrochemical biosensor based on an aptamer and a preparation method thereof, which is a three-electrode system, the three-electrode system comprises a working electrode, a reference electrode and a counter electrode, and the base materials of the working electrode, the reference electrode and the counter electrode are all polylactic acid micro-needles with a sputtered gold layer; the modification material of the working electrode comprises 6-mercapto-1-hexanol, 3-aminopropyltriethoxysilane, glutaraldehyde, an amino-modified cortisol aptamer and bovine serum albumin. The micro-needle electrochemical biosensor based on the aptamer and the preparation method thereof are adopted to construct a three-electrode micro-needle system for detecting cortisol in tissue fluid, continuous and painless detection can be realized, the compliance of patients is improved, the detection limit is low, the detection range is wide, the sensitivity is high, and the needs of human body for daily detection of cortisol can be met.

The invention belongs to the field of biosensing and biological interface engineering, and particularly relates to a double-enhanced bionic glycopeptide electrochemical biosensor based on anti-pollution and anti-enzymolysis stability and a preparation method of the double-enhanced bionic glycopeptide electrochemical biosensor. The invention is inspired by glycoprotein in vascular endothelial cell glycocalyx, a novel glycopeptide material capable of enhancing biological pollution resistance and protease hydrolysis resistance stability is constructed by performing glycosylation modification at the C terminal of a polypeptide sequence, and the novel glycopeptide material is applied to a complex biological medium and has remarkable performance superior to that of non-glycosylated peptide.

The invention discloses a high-performance biosensor based on a g-C3N4 / TiO2 heterojunction as well as a preparation method and application of the high-performance biosensor, and belongs to the technical field of biosensing and food safety detection. The sensor is constructed by taking a glassy carbon electrode as a substrate and sequentially modifying a g-C3N4 / TiO2 heterojunction composite material and diamine oxidase (DAO). The g-C3N4 / TiO2 heterojunction is prepared through a one-step calcination method, a type II p-n junction structure is formed, photo-generated charge separation and interface electron transfer are effectively promoted, and the conductivity, catalytic activity and enzyme immobilization capacity of the electrode are remarkably improved. The invention discloses a synergistic mechanism of heterojunction interface enhanced histamine selective adsorption and catalytic reaction through density functional theory calculation. The sensor shows excellent detection performance on histamine: the linearity is good in a range of 0.05-10 mM, and the detection limit is as low as 0.075 M; the selectivity is still higher than 93% in the presence of an interferent with ten times of concentration; when the method is applied to detection of actual samples of beef, mutton, fish and chicken, the adding standard recovery rate is 93.60%-101.8%, and the relative standard deviation is smaller than 5%. The sensor has the advantages of high sensitivity, good selectivity, strong anti-interference capability, good reproducibility and the like, and a reliable new method is provided for rapid and accurate screening of histamine in food.

The invention discloses a portable electrochemical biosensor for detecting vibrio parahaemolyticus, the principle of the invention can be also suitable for detection of other pathogenic microorganisms, and the portable electrochemical biosensor comprises a PVC substrate, a sample pad, a capture pad, a screen printing electrode and a water absorption pad. According to the invention, the advantage of high sensitivity of electrochemistry and the advantage of no separation of the test strip are combined together, the vibrio parahaemolyticus is captured by using the aptamer and is fixed on the detection line, the signal probe is dropwise added, the electrochemical workstation is used for detection, and quantitative detection of the vibrio parahaemolyticus is realized by adopting a signal subtraction output mode. The method has the advantages of low cost, high detection speed, high sensitivity, simplicity in operation and the like. The requirements of customers for on-site rapid detection can be met, and food poisoning of patients can be effectively prevented.

The utility model provides a glucose solution filling assembly for testing an electrochemical biosensor and a detection device, and relates to the technical field of biosensor detection, the glucose solution filling assembly comprises a liquid storage tank, a confluence piece, a constant-temperature water bath kettle and a sensor assembling assembly, the confluence piece is provided with a liquid inlet end and a liquid outlet end, the liquid inlet end is communicated with the accommodating cavities in a time-sharing manner and is higher than the liquid outlet end, the constant-temperature water bath pot receives a glucose solution discharged from the liquid outlet end, and the sensor assembling component fixes the electrochemical biosensor; in a non-filling state, the sensor assembling component and the confluence piece are close to and far away from the constant-temperature water bath kettle respectively, and in a filling state, the sensor assembling component and the confluence piece exchange position states respectively. By optimizing the pipeline connecting structure, the problems that an existing pipeline is complex in arrangement and large in occupied space are solved, and in the filling state and the non-filling state, the problem that glucose solution filling flexibility is poor is solved through movement matching of the confluence piece and the sensor assembling assembly.

The invention provides an electrochemical biosensor having high sensitivity, high selectivity, mechanical stability and real-time monitoring capability, a method for manufacturing the electrochemical biosensor, and a virus detection system. The electrochemical biosensor comprises a substrate, a working electrode and a reference electrode, the working electrode and the reference electrode are formed on the substrate, the working electrode comprises an electrode base material, an interface molecular layer and a biological recognition layer, a dendritic gold layer is formed on the surface of the electrode base material, interface molecules of the interface molecular layer are 1-pyrene butyric acid N-hydroxysuccinimide ester, namely PBASE, and the biological recognition layer is formed on the surface of the electrode base material. One end is combined with the dendritic gold layer, and the active ester at the other end is coupled with biological recognition molecules, so that a compact, uniform and anti-washing biological recognition layer is formed.

The present invention relates to: a transition metal complex having a bidentate ligand including a pyrazole, a triazole, a tetrazole, an oxadiazole, or a thiadiazole, etc., wherein the transition metal complex is useful as an electron transfer mediator in a continuous blood glucose monitor, etc., for measuring a blood glucose concentration; and a redox polymer comprising the same. The transition metal complex and the redox polymer can exchange electrons quickly and smoothly between an enzyme and an electrode, and thus can be effectively used in a continuous blood glucose biosensor.

The application discloses a water barrier enhanced dendritic dextran-polypeptide conjugate anti-fouling electrochemical biosensor and a preparation method thereof, and belongs to the field of biosensing and biological interface engineering. Specifically, Y-type zwitterionic branched polypeptides are connected to dextran to construct a dense and spatially extended interface layer. The branched macromolecular framework effectively shields the electrode surface, avoiding direct contact with non-specific biomolecules, thereby reducing biological fouling and improving interface stability. Functionally, dextran and zwitterionic peptides both have excellent hydrophilicity and hydration capacity. By covalently integrating these two anti-fouling materials into a dendritic structure, a highly hydrated interface barrier is established, effectively inhibiting non-specific protein adsorption and matrix interference. Importantly, the synergistic combination of dextran and zwitterionic peptides is expected to be superior to single use, as it simultaneously possesses steric exclusion, hydration layer protection and charge-neutral surface properties.

The invention provides a PP2A / PDA-ZnO / GCE electrochemical biosensor as well as a preparation method and application of the PP2A / PDA-ZnO / GCE electrochemical biosensor. The sensor comprises a glassy carbon electrode, an immobilized enzyme layer is arranged on the surface of the glassy carbon electrode, and the immobilized enzyme layer comprises protein phosphatase 2A and nano-zinc oxide coated with polydopamine; the mass ratio of the protein phosphatase 2A in the immobilized enzyme layer to the polydopamine-coated nano-zinc oxide is 5: 8-5: 2, and the molar ratio of dopamine hydrochloride used as raw materials of the polydopamine-coated nano-zinc oxide to the nano-zinc oxide is 1: 3-1: 2. The invention also provides a preparation method of the electrochemical biosensor. The electrochemical biosensor can be used for detecting diarrhetic shellfish poison in seawater and marine organisms, especially okadaic acid and dinosporin; the polydopamine-coated nano zinc oxide and the protein phosphatase 2A have a synergistic effect, so that the binding force is strong, the enzyme activity is good, the performance is stable, the reutilization is realized, and the cost is low.

An electrochemical biosensor chip for the simultaneous quantitative detection of a plurality of different target molecules in a biological fluid, wherein the biosensor chip comprises: a) a substrate with a microfluidic structure designed to guide the biological fluid, b) a plurality of electrochemically isolated detection modules arranged along the microfluidic structure, c) wherein each detection module is structurally assigned to a specific target molecule and differs from the other detection modules by at least one irreversible structural feature selected from: -Electrode geometry, -Electrode surface, -Surface chemistry, - or a combination thereof, d) wherein each detection module comprises a working electrode, a counter electrode and a reference electrode, e) wherein each detection module is linked to a fixed electrochemical redox system which defines a module-specific electrochemical operating window, f) wherein the electrochemical operating windows of the detection modules do not overlap, (g) and wherein the biosensor chip comprises at least one non-functionalized internal reference electrode configured for hardware-based signal normalization, independent of the chemical identity of the target molecules.

The application discloses an electrochemical biosensor based on specific nucleic acid aptamer fragments and glucose oxidase. The specific recognition of the same target object by the double nucleic acid aptamer is utilized to combine the modified metal organic framework compound and the magnetic nanoparticles with the target object to form a self-assembly structure, and the magnetic nanoparticles are separated out by utilizing the magnetism of the magnetic nanoparticles. Meanwhile, the specific catalytic action of the glucose oxidase on glucose produces hydrogen peroxide to further oxidize 3,3'-diamino benzidine to generate an electrochemical signal, and the metal organic framework compound and the magnetic nanoparticles both have peroxidase-like activity, which can further synergistically catalyze the oxidation of 3,3'-diamino benzidine by hydrogen peroxide, and the sensitivity is improved. Thus, based on the linear relationship between different concentrations of pathogen solutions and corresponding electrochemical signal intensities, the electrochemical biosensor realizes high-sensitivity detection of the hyacinth yellow rot fungus.

The invention relates to a disposable electrochemical biosensor for use in the sensitive determination of glyphosate (GLY), a herbicide, and the preparation method thereof. In the electrochemical biosensor of the invention, carboxymethyl cellulose (CMC) / hydroxyapatite (HaNP) nanobiocomposite was modified onto the surface of a disposable pencil graphite electrode (PGE). DNA aptamer (DNA APT), a specific bioreceptor of glyphosate, was immobilised on the CMC / HaNP-PGE surface.

The present invention relates to a cell-free transcriptional electrochemical biosensor and to the use of the same for detecting specific molecular analytes, such as specific antibodies, proteins, small molecules, nucleic acids, and derivatives thereof, in complex arrays of biological samples, such as plasma, serum, blood, saliva, sweat, and the like, wherein said biosensor is based on the activation of the transcription of a specific RNA strand, induced by recognition with the analyte. The invention further relates to a method for the detection of specific molecular analytes in complex arrays of biological samples, said method being based on the use of said cell-free transcriptional electrochemical biosensor.

Hybrid sensing materials and electrochemical sensors incorporating the hybrid sensing materials are disclosed, as well as methods of making and methods of use thereof. The hybrid material contains a plurality of MXene sheets having biorecognition elements conjugated thereto, preferably using copper-free click chemistry. The biorecognition element contains a binding partner to an analyte of interest. The electrochemical sensor includes a working electrode, which contains a substrate having the hybrid material deposited thereon, and optionally, a counter and / or reference electrode. Electrochemical sensors incorporating the hybrid materials can be used for non-invasive detection of the absence, the presence, and / or the concentration of biomarkers, such as nucleic acids and proteins, in a biological sample, for highly sensitive (down to attomolar limit of detection), specific, and reproducible detection of target analyte in a wide linear dynamic range (from attomolar to nanomolar).

The present application relates to a seaweed residue-based electrochemical biosensor and a preparation method thereof, which uses seaweed residue as raw material and chitosan as crosslinking agent, and prepares carbon aerogel CAs through sol-gel, vacuum freeze-drying and high-temperature carbonization process, and uses the CAs modified electrode (CAs / GCE) for DA detection. The present application uses high-temperature pyrolysis of nitrogen in seaweed residue to increase the disorder of C in CAs, which can effectively increase the active sites for dopamine detection and improve the electrochemical detection activity of the sensor for DA. CAs do not contain substances harmful to organisms or polluting to the environment, which not only solves the problems of high cost and limited application range of other raw materials, but also solves the problems of high value-added development and utilization of waste seaweed residue.

A biosensor is manufactured by printing electrodes on a substrate using metallic ink; printing a carbon surface using carbon-containing ink, the carbon surface being in electrical communication with the electrodes; immersing the substrate in an acid bath having a pH of less than 3.0 and applying a first voltage cycle, and immersing the substrate in a basic bath having a pH of at least 13.0. Each of the first voltage cycle and the second voltage cycle comprise a voltage that is less than 0 V and that is greater than 0 V.

The application relates to an electrochemical biosensor and a preparation method thereof and application thereof in dopamine detection, wherein the photoelectrochemical biosensor adopts a three-electrode system, a glassy carbon electrode modified by a single-atom catalyst with Ni-N4 coordination is used as a working electrode, an Ag / AgCl electrode is used as a reference electrode, and a platinum wire electrode is used as a counter electrode. The electrochemical biosensor provided by the application uses the glassy carbon electrode modified by the single-atom catalyst with Ni-N4 coordination as the working electrode, the single-atom catalyst has excellent electron conductivity and extremely high catalytic activity, a large specific surface area, high dispersity, more active sites, high atom utilization rate and the like, the electrochemical biosensor prepared based on the single-atom catalyst has high sensitivity in dopamine detection, can clearly distinguish common interferents such as ascorbic acid, dopamine and uric acid, and has good selectivity.

The invention discloses an electrochemical biosensor based on a TdT-Cas12a reaction system and a HaeIII enzyme and an Alzheimer's biomarker detection method.The electrochemical biosensor comprises a TdT reaction system and a Cas12a reaction system, the TdT reaction system comprises a TdT enzyme, a TdT buffer solution, deoxyadenine triphosphate (dATP) and a marker nucleic acid conversion product, and a TdT extension product is obtained through reaction; the Cas12a reaction system comprises a reaction buffer solution, Cas12a protein, crRNA and a TdT extension product, and a Cas12a system product is obtained after incubation; the construction method of the electrochemical biosensor comprises the following steps: combining a biological probe P on the surface of a gold electrode to finish electrode surface modification; and adding a Cas12a system product to the surface of the gold electrode, and continuing incubation. The electrochemical biosensor has excellent sensitivity and specificity, can significantly improve the detection sensitivity of AD related proteins in NDE, can be used for analysis of human serum samples, and is high in recovery rate.

This invention belongs to the field of rapid detection technology, specifically relating to a rapid, real-time detection method for influenza A based on electrochemical biosensors. This invention provides an aptamer that specifically recognizes the influenza A virus, and uses a pairing affinity reagent to enrich the aptamer onto magnetic beads to prepare a probe that specifically recognizes the influenza A virus. Then, using this probe, MB solution, and screen-printed electrodes, an electrochemical biosensor that specifically recognizes the influenza A virus is fabricated. Qualitative or quantitative detection of influenza A virus using the electrochemical biosensor of this invention eliminates the need for complex pretreatment and viral nucleic acid amplification, greatly simplifying the operation. The results are stable and reliable, making it suitable for real-time detection applications.