24 results about "Glassy carbon electrode" patented technology

The application discloses a kind of glucose oxidase sensors based on modified multi-walled carbon nanotube modification, it is related to glucose oxidase sensor technical field, including the following steps: (1) modified multi-walled carbon nanotube preparation;(2) glassy carbon electrode is carried out surface polishing treatment;(3) obtain modified multi-walled carbon nanotube dispersion;(4) obtain glucose oxidase liquid;(5) glucose glucose oxidase liquid impregnation electrode;(6) using Nafion solution covers electrode;The sensor obtained after the electrode is modified by introducing modified multi-walled carbon nanotube in the application, not only has higher glucose detection sensitivity, but also has excellent stability.

The application discloses a method for detecting polychlorinated biphenyl by using an electrochemical aptamer sensor. x The sensor comprises a glassy carbon electrode, a surface of a detection end of the glassy carbon electrode is decorated with an electroactive nanomaterial, the electroactive nanomaterial comprises Ti3C2T 0000001 Nanosheet, a conductive polymer material is embedded in an interlayer structure of the nanosheet and forms a composite nanomaterial, and gold nanoparticles are deposited on a surface of the composite nanomaterial; a capture chain is self-assembled on the electroactive nanomaterial, a specific aptamer probe is combined on the capture chain, a DNA double-stranded structure is formed, and an electroactive label is introduced. In the application, the sensor has the advantages of wide detection range, low detection limit, strong anti-interference ability, good stability and the like, can realize specific detection of polychlorinated biphenyl, has the advantages of low cost, short time consumption, high accuracy, good adaptability and the like, and has important significance for rapid detection of polychlorinated biphenyl.

This invention discloses a functionalized biomodified electrode for rapid pathogen detection and its preparation method, relating to the fields of biosensing and electrochemical detection technology. It includes a glassy carbon electrode substrate, the surface of which is sequentially modified with a reduced graphene oxide layer, an electropolymerized polydopamine film, and an electrodeposited gold nanoparticle layer, forming a composite nanomaterial modified electrode. Antibodies are captured and fixed to the electrode surface through covalent interactions. This functionalized biomodified electrode for rapid pathogen detection and its preparation method, using the same electrochemical workstation, first electropolymerizes dopamine to form a film and then electrodeposits gold nanoparticles. This allows for precise control of film thickness, gold particle size, and coverage density by parameters such as polymerization potential, scan cycles, deposition potential, and deposition time. This avoids batch-to-batch fluctuations caused by dissolved oxygen and solution disturbances in traditional chemical methods, reducing the relative standard deviation of peak current detection from different batches of electrodes from 18.7% to 4.2%–4.5%.

The application relates to a chromium ion form analysis method based on electrochemical and Raman bimodal detection signals. Au-Ag Janus NPs solution is added dropwise on the surface of a glassy carbon electrode, the DPV signal value and the Raman signal value of a to-be-detected solution containing Cr 6+ and Cr 3+ are detected, the concentration of Cr 6+ in the to-be-detected solution is obtained, Cr 6+ in the to-be-detected solution containing Cr 3+ and Cr 3+ is oxidized into Cr 6+ under the conditions of strong alkalinity and heating by using potassium permanganate, then a reducing agent is added to obtain a mixed solution, the concentration of Cr 6+ in the mixed solution is detected through the DPV signal value and the Raman signal value, Cr 3+ is completely converted into Cr 6+ , the total chromium concentration is measured, finally the concentration of Cr 3+ is obtained by subtraction, and finally the chromium ion form analysis is realized. The method improves the accuracy and efficiency of Cr ion form detection, and is suitable for rapid analysis of Cr ion forms in environment and biological samples.

The application belongs to the field of thin film transistor sensing and biomarker detection, and relates to an enzyme-free liquid gate thin film transistor sensor for detecting a myocardial injury marker, which comprises a source electrode, a drain electrode and a functionalized gate electrode, the source electrode and the drain electrode are noble metal interdigital electrodes deposited on the surface of a SnO2 thin film, the interdigital array region is connected through the SnO2 thin film, that is, a channel region; the functionalized gate electrode is formed by sequentially constructing a gold nanoparticle layer, a polydopamine connecting layer and a specific aptamer covalent fixing layer on the surface of a glassy carbon electrode, and serves as a biological recognition interface; the myocardial injury marker is detected by recognizing the threshold voltage offset generated by the myocardial injury marker. In view of the super-sensitivity detection requirement of a clinical myocardial injury marker, the sensor constructed by the application is used for detecting the myocardial injury marker, has a super-wide detection range (0.001~1000 ng mL ‑1 ) and super-high sensitivity, exhibits an extremely low detection limit (as low as 1 pg mL ‑1 ) and good selectivity, and is especially suitable for precise detection of trace myocardial injury markers.

This invention relates to the field of electrochemical detection technology for vitamin E, specifically to an electrochemical detection device and method for vitamin E. The method includes: utilizing a detection system composed of a glassy carbon electrode, a saturated calomel electrode, and a platinum wire electrode; performing a series of optimizations and screenings to determine the SWV electrochemical detection method; and electrode pretreatment: using 0.05 μm alumina powder to perform circular polishing on the glassy carbon electrode in both directions for 3-4 minutes, followed by ultrasonic cleaning with anhydrous ethanol and pure water for three minutes each time. Finally, the electrode is scanned using the SWV method in a prepared buffer solution until it stabilizes. The beneficial effects are: this invention is convenient and simple to operate, has a simple formulation that greatly optimizes the detectable limit, has low manufacturing cost and is readily available, and requires no electrode modification; the lowest detectable concentration is far below the minimum normal range of vitamin E in human blood.

The application discloses a kind of natural product antiviral drug screening method based on hexagon protein and application, belong to active ingredient screening and antiviral drug development field.The method includes: preparation nitrogen-doped mesoporous carbon and silver nanosheet composite solution, drop coating on the surface of pretreated glassy carbon electrode, after drying by activation, hexagon protein incubation, blocking and enzyme label antibody reaction, construct electrochemical sensing electrode;With the electrode, the sample to be screened natural product is incubated, and the current response signal is detected;According to signal change combination inhibition rate formula evaluation antiviral activity.The application takes hexagon protein as recognition target, based on the principle of competitive immunoassay, realizes the specific, high sensitivity detection of antiviral active ingredient in natural product, with the advantages of fast operation, low cost, small sample consumption, high throughput, etc., provides effective technical support for the mining of antiviral active ingredient in natural product such as traditional Chinese medicine.

This invention belongs to the field of graphene materials and discloses a magnetic nitrogen-doped reduced graphene oxide, its preparation method, and its application. The method includes the following steps: (1) preparation of frangipani extract; (2) adding iron salt, sodium acetate, and frangipani extract to an aqueous solution of graphene oxide, ultrasonically mixing until homogeneous, and then carrying out a hydrothermal reaction. After the reaction is complete, the solid is separated using a strong magnet and washed, and then freeze-dried to obtain magnetic nitrogen-doped reduced graphene oxide. The prepared magnetic nitrogen-doped reduced graphene oxide material, used as a glassy carbon electrode modification material, exhibits excellent electrochemical performance and can be applied in the rapid detection of Cd(II). The synthesis method of this invention has the advantages of being simple, easy to implement, and environmentally friendly. The prepared magnetic nitrogen-doped reduced graphene oxide has important application value in sensing, catalysis, optics, and electronics.

This invention discloses a nickel-based dithioene-transition metal MOFs / MWCNTs / GCE 5-HT electrochemical sensor, comprising a working electrode, a reference electrode, a counter electrode, and a buffer solution. NiZn-MOFs are prepared using P2S5, dioxane, dimethyl 4,4'-(2-hydroxyacetyl)dibenzoate, NiCl2·6H2O, THF, KOH, and Zn(NO3)2·4H2O. These are then ultrasonically composited with carboxylated carbon nanotubes to obtain NiZn-MOF / MWCNTs. A glassy carbon electrode is modified to obtain the working electrode. This electrochemical sensor can be used for 5-HT detection. The multi-walled carbon nanotubes exhibit good conductivity, and their combination with the redox-active three-dimensional NiZn-MOFs with unsaturated coordination sites improves the conductivity and catalytic performance of the composite material, solving the problems of low electrocatalytic activity and low sensitivity in 5-HT detection.

The application discloses a kind of molecularly imprinted electrochemical sensor capable of detecting glutamic acid and serotonin simultaneously.The molecularly imprinted electrochemical sensor includes glassy carbon electrode, and (1) amino-functionalized reduced graphene oxide and (2) double-template molecularly imprinted polymer with glutamic acid and serotonin as template molecules and o-phenylenediamine as monomer successively modified on the surface of glassy carbon electrode.Compared with prior art, the molecularly imprinted electrochemical sensor of the application can realize simultaneous detection of non-electrically active glutamic acid and electrically active 5-hydroxytryptamine, thereby saving detection operation and cost, showing good linear relationship and low detection limit for Glu and 5-HT in the concentration range of 1-100 μM, and having good precision, accuracy, selectivity and stability.

The application provides a sensor with antioxidant and antifouling properties and a preparation method and application thereof, and belongs to the technical field of marine chemistry. The sensor takes a glassy carbon electrode (GC) as a substrate, adopts polyaniline as a solid contact layer, and takes a calcium ion selective membrane (ISM) as a detection core. The innovation of the sensor is that a fucoidan-based functional polypeptide (PFp) is modified on the ISM to construct an antifouling layer. The PFp layer forms a triple synergistic defense mechanism of "anti-adhesion-sterilization-antioxidation". Experiments prove that the sensor can effectively inhibit the adhesion and colonization of bacteria such as escherichia coli and staphylococcus aureus and chlorella, and significantly slow down the oxidative decay of the sensing membrane. In addition, when the sensor is used for calcium ion detection in actual seawater, it exhibits excellent long-term stability and high precision, and provides an innovative strategy for continuous in-situ monitoring in complex media.

This invention belongs to the field of electrochemiluminescence and provides an electrochemiluminescence aptamer sensor for the detection of isobutyryl fentanyl (IBF), its preparation, and its application. An apt@Ni-MOFs / cDNA / Ag-MOGs / SiO2 electrode with electroluminescence and specific recognition properties is modified onto the surface of a glassy carbon electrode (GCE) to form the modified electrode apt@Ni-MOFs / cDNA / Ag-MOGs / SiO2 / GCE. This modified electrode is used as the working electrode, an Ag / AgCl electrode as the reference electrode, and a platinum electrode as the counter electrode. IBF was detected by electrochemiluminescence in a PBS buffer solution containing 0.15 mol / L K2S2O8 at pH 7.4, and the corresponding regression equation was obtained; ΔECL = 2.4 × 10⁻⁶. 4 + 1.6×10 3 ×log C (g / L), correlation coefficient R 2 =0.999, detection limit is 3.3 × 10 –15 g / L. This invention exhibits good selectivity, high sensitivity, and a wide linear range.

The application discloses a preparation method of a molecular imprinting electrochemical sensor for detecting sodium pentachlorophenol and detection application thereof, and is characterized by comprising the following steps: after ultrasonic dispersion of a sodium pentachlorophenol molecular imprinting polymer suspension, the suspension is drop-coated on the surface of a treated glassy carbon electrode, and the molecular imprinting electrochemical sensor is obtained by standing and drying at room temperature; and a sodium pentachlorophenol detection method is also provided and comprises the following steps: the sensor is placed in a phosphate buffer solution containing Ru(bpy)3 2+ TPrA is polarized, and an initial ECL signal intensity I is recorded; after a to-be-detected PCP-Na solution is added, the ECL intensity I0 is determined by standing and reacting, the ECL signal change value ΔI=I-I0 is taken as a response index, the PCP-Na concentration in the to-be-detected PCP-Na solution is calculated according to the linear relationship between the PCP-Na solution concentration and ΔI, and the method has the advantages of good selectivity and stability, high sensitivity and accuracy.

This invention belongs to the field of electrochemical sensor technology and aims to solve the problems of low sensitivity, insufficient charge transport efficiency, and weak target enrichment ability of existing electrochemical detection methods for niclosamide. It provides a highly sensitive electrochemical detection method and sensor for niclosamide based on MOF / COF composite materials. The sensor uses a glassy carbon electrode modified with MOF / COF composite material as the working electrode, combined with an auxiliary electrode and a reference electrode to form a three-electrode system. It utilizes the synergistic effect of the high specific surface area and high catalytic activity of MOF and the good conductivity and ordered porous structure of COF to enhance the adsorption, enrichment, and electron transfer efficiency of niclosamide. The detection method achieves accurate detection of niclosamide by optimizing electrochemical test parameters and employing square wave voltammetry. This invention features a low detection limit, wide linear range, strong anti-interference ability, excellent stability and reproducibility, and can rapidly detect niclosamide in water, soil, fish, and tablets, possessing broad practical application value.

Recently, aptamers have been considered in cancer diagnosis and treatment applications by binding to various bioreceptor molecules. Given that the p53 protein is responsible for approximately 50% of cancers, its identification is promising, but so far, no aptamer DNA sequence has been designed for the p53 protein and aptamer-based sensor. The purpose of this invention is to develop a nanoparticle-based aptamer sensor and use the p53 bioreceptor for cancer diagnosis with high sensitivity in the shortest time. In this regard, a DNA aptamer-based sensor was used on a glassy carbon electrode coated with gold nanoparticles / graphene oxide / conductive polymer . This sensor was created by the gold nanoparticles / aptamer-toluidine blue enhancer. The results obtained under optimal conditions of electrochemical investigation using amperometry indicated a detection limit of 0.29 picograms / mL in phosphate buffer and 0.341 picograms / mL in human blood plasma and a linear range of 1 to 300 picograms / mL for the sensor. This invention demonstrates the excellent and controllable performance of a modified carbon electrode to create a suitable sensor for detecting the cancer marker p53 protein.

This invention discloses a ratiometric electrochemical sensor, its preparation method, and a method for simultaneously detecting methyl parathion and carbendazim. The sensor uses a CeCoZn-MOF / NBA / CNHs-modified glassy carbon electrode as the working electrode, a saturated KCl-type Ag / AgCl as the reference electrode, and a platinum wire as the counter electrode. Preparation involves electrode pretreatment, CeCoZn-MOF synthesis, composite material compounding, dispersion preparation, and electrode drop-coating modification. Differential pulse voltammetry is used for detection, with Nile Blue A as the internal standard probe. Quantification is based on the current ratio of the target analyte to the internal standard. The linear detection range for methyl parathion is 0.05–15 μg / mL, and for carbendazim, it is 0.05–4 μg / mL, with correlation coefficients greater than 0.99 for both. This sensor exhibits strong anti-interference capabilities, high sensitivity and accuracy, with a recovery rate of 91.0%–109.2% in actual agricultural product samples. It enables rapid, simultaneous, and accurate detection of methyl parathion and carbendazim, and is suitable for rapid on-site detection of pesticide residues in agricultural products.

The application relates to the technical field of biological detection, in particular to an electrode based on a PLL / MWCNTs-NH2 electrode modification material and a preparation method and application thereof. A glass carbon electrode (GCE) is taken as a substrate, and polylysine (PLL) and amino-modified multi-walled carbon nanotubes (MWCNTs-NH2) are sequentially modified. By optimizing detection conditions such as pH, scanning speed and PBS concentration, the sensor has a good linear response to 8-OHdG in the range of 0.0044 muM to 14.12 muM, and the detection limit is as low as 0.2 nM. The sensor has strong anti-interference ability, can effectively eliminate the influence of interference substances such as uric acid, and has good stability and repeatability. In actual urine sample detection, the detection result is similar to that of an ELISA method, and the sensor has wide application prospects.

The application discloses a preparation method of an electrochemical sensor based on a hollow bowknot structure SeVs-LaSe2-CoSe2 / C nano material, a La1Co1-MOF precursor is synthesized through a one-step solvothermal method, a SeVs-LaSe2-CoSe2 / C sensing material is obtained by doping selenium powder and high-temperature pyrolysis, and the sensing material is gradually modified with acetylcholinesterase (AChE), Nafion and a clean glassy carbon electrode surface, so that an AChE-NF / SeVs-LaSe2-CoSe2 / C / GCE biosensor electrode is finally prepared; the method is simple and easy to control, the obtained material is a bowknot structure formed by super-thin hollow nanotubes, the electrochemical active surface area is increased, more active sites are provided for AChE loading, and the electrochemical performance of the sensor is greatly improved.

This invention discloses an electrochemiluminescence aptamer sensor for imatinib detection, its preparation method, and its detection application. Addressing the problems of cumbersome procedures and insufficient sensitivity in existing detection methods, this invention constructs the sensor through the following steps: first, gold is deposited on the surface of a glassy carbon electrode; then, double-stranded DNA, bovine serum albumin, imatinib solutions of different concentrations, and a carboxyl-modified activated signal probe solution are incubated sequentially to obtain a sensor for imatinib detection. This invention also discloses a method for detecting imatinib using this sensor. This method combines the high sensitivity of electrochemiluminescence technology with the high specificity of aptamers, possessing advantages such as high sensitivity, low detection limit, wide linear range, rapid detection, simple operation, and small sample volume. It has been successfully applied to the detection of clinical blood samples taken with imatinib.

This invention discloses a method for preparing a molecularly imprinted electrochemical sensor for detecting cyclic adenosine monophosphate (cAMP). The sensor uses reduced graphene oxide (RGO) and gold nanoparticles as modifying materials. RGO is drop-coated onto the surface of a glassy carbon electrode and dried to obtain a modified electrode RGO / GCE. The RGO / GCE is then placed in a sulfuric acid deposition solution containing chloroauric acid, and gold nanoparticles are used to modify the RGO / GCE surface using a potentiostatic method to form a gold substrate, resulting in a deposited electrode AuNPs / RGO / GCE. The AuNPs / RGO / GCE is then electropolymerized in an electrolyte polymerization solution containing the template substance cAMP and the functional monomer o-phenylenediamine to obtain a dense and insulating polymer film. The polymerized electrode is immersed in an elution solution and eluted using cyclic voltammetry to obtain MIP / AuNPs / RGO / GCE. This sensor exhibits specific recognition selectivity for cAMP, high detection sensitivity, low detection limit, good reusability, and stability.

This invention provides an enzyme biofuel cell anode, its preparation method, and its application. The anode is obtained using a dual-enzyme carrier layered independent immobilization strategy. The dual-enzyme carrier consists of carbonized square tubular polypyrrole as a glucose oxidase carrier material and mineralized trehalose hydrolase. Trehalose hydrolase is embedded in a metal-organic framework material using a biomimetic mineralization method, forming a bioactive mineralized trehalose hydrolase layer. Carbonized square tubular polypyrrole is used as the glucose oxidase carrier material. The glucose oxidase layer and the mineralized trehalose hydrolase layer are modified onto a glassy carbon electrode using a layered immobilization method. This method, applied to enzyme biofuel cells, avoids the problem of unexpected homo / heteroenzyme cross-linking in multi-enzyme cascade reactions and improves the utilization rate between different enzyme substrates, thereby increasing the efficiency and electron yield of multi-enzyme cascade reactions.

The application discloses an electrochemical aptamer sensor for high-sensitivity detection of alpha-amatoxin and a preparation method and application thereof, and belongs to the technical field of electrochemical detection. The working electrode of the sensor is a glassy carbon electrode, gold nanocrystals are used to modify the electrode first, then aptamers are connected to the gold nanocrystals through gold-sulfur bonds, and the remaining active sites are closed by using mercaptohexanol. The electrochemical aptamer sensor has high selectivity and sensitivity for alpha-amatoxin, and has the advantages of simple sample pretreatment steps, rapidness and convenience. The detection result of an actual human sample is satisfactory. The electrochemical aptamer sensor prepared by the application has been successfully applied to the detection of alpha-amatoxin in human urine, and has the advantages of extremely low detection limit, wide detection range, excellent selectivity and stability.

The application provides an electrochemical aptamer sensor for detecting streptomycin and a preparation method thereof, and the preparation method comprises the following steps: S1, pretreating a glassy carbon electrode; S2, preparing Cu-ZIF-8@AuNPs; performing nitrogen plasma treatment on the Cu-ZIF-8@AuNPs; S3, dropping the plasma modified Cu-ZIF-8@AuNPs suspension on the pretreated glassy carbon electrode and drying; S4, modifying the plasma modified Cu-ZIF-8@AuNPs / GCE composite electrode by using streptomycin aptamer to obtain a modified electrode; S5, performing blocking treatment by using BSA, and then performing washing and drying to obtain the electrochemical aptamer sensor; the plasma modified Cu-ZIF-8@AuNPs can significantly improve the electron transfer efficiency, and can enhance the streptomycin detection sensitivity, selectivity and stability of the electrochemical aptamer sensor.