270 results about "Glassy carbon electrode" patented technology

The invention discloses an all-solid-state calibration-free ion concentration detection method. The method comprises the following steps: constructing a plurality of traditional three-electrode detection systems; in each traditional three-electrode detection system, current and impedance signals are synchronously acquired through a step potential electrochemical spectrum and an electrochemical impedance spectrum, and interface kinetic parameters are analyzed; on the basis of a traditional three-electrode detection system, an original reference electrode is removed, a counter electrode is reserved, all glassy carbon electrodes with gradient membrane volumes are connected in series one by one to obtain a new three-electrode detection system, the new three-electrode detection system is immersed in a to-be-detected solution, a preset potential is applied, and through transient current response in combination with calibrated kinetic parameters, the gradient membrane volumes of the glassy carbon electrodes are detected. And performing inversion to obtain the ion concentration of the to-be-detected solution. According to the method, automatic calibration is realized by analyzing interface process kinetic parameters of different-volume film ion selective electrodes and calculating the slope to generate a built-in standard curve. According to the method, interface process parameters are obtained through transient current, and dependence of a traditional detection system on the stable potential of a reference electrode is eliminated.

The invention discloses a biosensor for detecting Alzheimer's disease markers as well as a construction method and application thereof, and relates to the technical field of biosensors. The construction method comprises the following steps: after a glassy carbon electrode is cleaned, dropwise adding a RuSi NPs (at) CS compound on the surface of the glassy carbon electrode to obtain a RuSi NPs (at) CS / GCE electrode; and immersing the RuSi NPs coated CS / GCE electrode into a PHL: S double-chain solution, and carrying out an incubation reaction to obtain the biosensor. The RuSi NPs (at) CS compound is obtained by carrying out mixed reaction on ruthenium-silicon nanoparticles and chitosan; pHL: S double chains contained in the PHL: S double-chain solution are obtained by carrying out incubation reaction on carboxyl-activated PHL chains and S chains. The biosensor has the advantages of high accuracy, strong sensitivity, good selectivity and the like, and can be applied to accurate detection of the Alzheimer's disease marker A beta oligomer.

The invention provides a preparation method of a plate-shaped glassy carbon electrode, which comprises the following steps: curing a resin raw material into a plate-shaped resin block, carbonizing in an inert atmosphere, and respectively introducing a nitrogen source and a boron source for doping operation to obtain a co-doped plate-shaped resin block precursor; placing the co-doped plate-shaped resin block between two porous graphite plates, and carrying out high-temperature treatment to obtain a glassy carbon matrix; and immersing the glassy carbon substrate into the adhesion layer solution to form an adhesion layer, transferring the adhesion layer into a deposition solution which comprises a bismuth-containing solution and a gold-containing solution, forming bismuth-gold nano-dots on the adhesion layer, and washing and drying the bismuth-gold nano-dots to obtain the plate-shaped glassy carbon electrode. Through directional arrangement of crystal orientations, the tantalum carbide coating achieves higher electrical conductivity and thermal conductivity. And the sensitivity and the service life of the plate-shaped glassy carbon electrode are obviously improved and prolonged.

The invention discloses a dopamine sensor working electrode based on an MOF material and a preparation method thereof, and belongs to the technical field of electrochemical sensing. The working electrode is composed of a pure MOF Cu-HHTP modified glassy carbon electrode and a Nafion film covering the surface of the glassy carbon electrode, and the preparation method of the working electrode comprises the following steps: synthesizing Cu-HHTP (Cu < 2 + > and a hexahydroxy triphenyl ligand are coordinated to form a two-dimensional honeycomb layer) through a solvothermal method, dispensing Cu-HHTP dispersion liquid on the surface of the glassy carbon electrode, and then covering the glassy carbon electrode with the Nafion film to form the combined electrode. The dopamine sensor prepared by the preparation method disclosed by the invention has high sensitivity, high anti-interference capability and long-term stability. The preparation process is simple, complex conductive additives are not needed, and the method is suitable for rapid and accurate detection of dopamine in complex biological samples.

The invention provides an electrochemical sensor for identifying amino acid enantiomers and a preparation method and application thereof, and relates to the technical field of electrochemistry, the sensor comprises a glassy carbon electrode and a xylose-inulin composite coating coated on the glassy carbon electrode. The preparation method comprises the following steps: S1, preparing the xylose-inulin composite material in a self-assembly manner; and S2, dispensing the xylose-inulin composite material obtained in S1 on the surface of a glassy carbon electrode, and airing to obtain the xylose-inulin modified glassy carbon electrode. The glassy carbon electrode modified by the composite material has a large number of active sites, and the modified electrode shows selective recognition on amino acid enantiomers by effectively utilizing the synergistic effect of xylose and inulin. The electrode disclosed by the invention has good stability, specificity and chiral recognition capability on the amino acid enantiomers, and has good application prospects in quantitative analysis of the amino acid enantiomers.

The invention relates to the technical field of organic synthesis, in particular to 1-chloro-8-fluorine-7-isopropyl benzofuro [2, 3-c] pyridine as well as a synthesis method and an application of the 1-chloro-8-fluorine-7-isopropyl benzofuro [2, 3-c] pyridine. According to the invention, 1-chloro-8-fluoro-7-isopropyl benzofuro [2, 3-c] pyridine and nanogold are cooperated to cover the surface of a glassy carbon electrode (GCE), and a novel electrochemical modified electrode AuNPs / 1 / GCE is developed. The modified glassy carbon electrode shows good selectivity, high stability and sensitivity and wide detection range on the detection of the antibiotic furacilin.

The invention discloses a hexachlorophenol electrochemical sensor built based on NiFe-coated C / MoO3 and a preparation method and application thereof.The hexachlorophenol electrochemical sensor comprises a working electrode, an auxiliary electrode and a reference electrode, the working electrode is a NiFe-coated C / MoO3 modified electrode and is composed of a glassy carbon electrode and a NiFe-coated C / MoO3 composite material modified on the glassy carbon electrode, the auxiliary electrode is a NiFe-coated C / MoO3 modified electrode, and the reference electrode is a NiFe-coated C / MoO3 modified electrode. The NiFe (at) C / MoO3 composite material comprises a NiFe (at) C framework and MoO3 loaded on the NiFe (at) C framework, and the NiFe (at) C framework is formed by embedding NiFe bimetal nanoparticles into a porous carbon framework. The preparation method comprises the steps of synthesis of MoO3, synthesis of NiFe C, preparation of the modified electrode and preparation of the electrochemical sensor. The hexachlorophenol electrochemical sensor disclosed by the invention can be used for direct electrochemical detection without derivatization, and is high in selectivity, portable at low cost, ultrahigh in sensitivity and good in application prospect.

The invention relates to the technical field of electrochemical analysis and detection, in particular to a sensitive detection tert-butylhydroquinone modified glassy carbon electrode, a preparation method and application, the sensitive detection tert-butylhydroquinone modified glassy carbon electrode has high specific surface area and catalytic activity and good conductivity, sensitive detection of tert-butylhydroquinone can be achieved, and the application range is wide. The modified glassy carbon electrode comprises a glassy carbon electrode and a compound coating, the compound coating wraps the surface of the glassy carbon electrode, and the compound coating is composed of graphene oxide and a Ti-based MOF derivative; the preparation method comprises the following steps: (1) preparing MIL-125 (Ti); (2) preparation of TiO2 / NC; (3) preparation of 15% GO (at) TiO2 / NC; (4) preparing a dispersion liquid of the prepared 15% GO-coated TiO2 / NC composite material; (5) manufacturing a modified electrode; the application comprises the following steps: S1, establishing a concentration-electrochemical response signal relationship; and S2, measuring the concentration of the to-be-measured substance.

The present invention provides a homocysteine ​​electrochemical sensor, and its preparation method and application. The preparation method of the homocysteine ​​electrochemical sensor of the present invention comprises the following steps: adding a dispersion containing carbon nanomaterials to the surface of a glassy carbon electrode, baking and drying, to obtain a carbon nanomaterial-modified electrode; then placing the carbon nanomaterial-modified electrode in a gold salt aqueous solution, and using an electroplating method to deposit nanogold on the surface of the carbon nanomaterial-modified electrode, to obtain a homocysteine ​​electrochemical sensor; the high conductivity of gold nanoparticles is of great significance for improving the electrocatalytic performance of the composite material for homocysteine. The homocysteine ​​electrochemical sensor prepared by the present application has low cost, low detection limit, and good stability. In addition, the spiked recovery rate of homocysteine ​​in serum samples is good, which provides potential application value for the reliable determination of homocysteine ​​in biological systems and the study of homocysteine-related diseases.

The invention discloses a composite material modified electrode based on a functionalized single-walled carbon nanotube and application thereof, and belongs to the technical field of electrochemistry, the modified electrode comprises a glassy carbon electrode and a functionalized single-walled carbon nanotube-glucose composite material coating coated on the surface of the glassy carbon electrode; the mass ratio of functionalized single-walled carbon nanotubes to glucose in the coating is (0.2-5): 1, and the functionalized single-walled carbon nanotubes comprise at least one of hydroxylated single-walled carbon nanotubes, carboxylated single-walled carbon nanotubes and aminated single-walled carbon nanotubes, preferably hydroxylated single-walled carbon nanotubes. The composite material modified electrode provided by the invention has a large number of active sites, and by effectively utilizing the synergistic effect of the hydroxylated single-walled carbon nanotubes and glucose, the modified electrode shows excellent selective recognition capability on amino acid enantiomers and also shows good stability; and the method has a good application prospect in quantitative analysis of the amino acid enantiomers.

The invention belongs to the field of new materials, and discloses an electrode-based liposome adriamycin entrapment rate electrochemical detection method. According to the detection method, after a bipolar vertical ordered mesoporous silica film (bp-VMSF) is modified on an electrically activated glassy carbon electrode (p-GCE), separation, enrichment and electrochemical detection are integrated, and rapid and sensitive detection of adriamycin can be realized. The glassy carbon electrode is subjected to electrochemical activation pretreatment under the alkaline condition, bp-VMSF stably grows, the surface of the inner layer close to the p-GCE electrode is negatively charged, and the surface of the outer layer away from the electrode is positively charged. The asymmetric charge configuration enhances the adsorption capacity of positively charged adriamycin molecules on an electrode interface through electrostatic enrichment. The p-GCE adsorbs adriamycin and promotes electron transfer, and is combined with the synergistic enrichment effect of the bp-VMSF double-static nano-channel, so that the electrochemical response performance to adriamycin is jointly improved, a method is provided for rapid detection of the liposome adriamycin encapsulation efficiency, and the p-GCE has a good prospect in evaluation of liposome adriamycin preparations.

The invention discloses a method for synchronously detecting multiple heavy metal ions in a water body, relates to a method for synchronously detecting multiple heavy metal ions in a water body, and belongs to the technical field of environmental monitoring. The problems of poor selectivity and organic interference during synchronous detection of multiple heavy metal ions are solved. According to the scheme, three heterojunction modification layers are constructed on a glassy carbon electrode to form a bionic photoelectric electrode; step-by-step photoelectric enrichment: 650nm laser is adopted,-0.6 V enables a middle layer to capture Cd < 2 + > and Pb < 2 + >, 532nm laser is adopted,-1.5 V pulse enables a surface layer to enrich Cu < 2 + > and Hg < 2 + >, and square waves repel organic matters; dissolution peaks are collected in different areas in differential pulse dissolution scanning, 12 keV X-ray excitation is synchronized, and quantification is performed only when the target ion characteristic dissolution peak potential is matched with the corresponding characteristic X-ray fluorescence signal at the same time. The method is used for synchronously and accurately detecting Cd < 2 + >, Pb < 2 + >, Cu < 2 + > and Hg

The invention relates to the technical field of electrochemical detection, in particular to a preparation method of a polydopamine modified nitrogen-doped carbon material and application of the polydopamine modified nitrogen-doped carbon material in electrochemical analysis and detection of copper ions. The preparation method comprises the following steps: calcining a Zn-MOF material in an inert atmosphere, removing metal zinc to obtain a porous nitrogen-doped carbon material with a hexagonal structure, mixing the nitrogen-doped carbon material with dopamine, and carrying out oxidative polymerization on the dopamine under an alkaline condition to obtain the polydopamine-modified nitrogen-doped carbon material. The polydopamine-modified nitrogen-doped carbon material prepared by the method has high electrochemical activity, rich active sites and excellent adsorption performance, is used for modifying a glassy carbon electrode to detect Cu < 2 + >, has high sensitivity to Cu < 2 + >, and overcomes the technical defects of electrode materials in the prior art.

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 invention discloses a kit for detecting an A beta oligomer. The kit comprises a nucleic acid aptamer-activator modified streptavidin magnetic bead, a methylene blue nucleic acid signal probe modified streptavidin magnetic bead, a Cas12a-crRNA compound and a synthetic gold nanocluster probe modified glassy carbon electrode. According to the invention, the beta-CD-AuNCs probe with high quantum yield is used as an electrochemiluminescence material, methylene blue is used as an electrochemiluminescence quencher, and through combination with CRISPR / Cas technology, signal change of an ECL reaction system is effectively regulated and controlled, and AbetaO detection is realized. The method has the advantages of strong detection specificity, good selectivity, high sensitivity and strong anti-interference capability on AbetaO, and has good market value.

The invention relates to the technical field of detection and identification of fentanyl substances, and discloses a selective quantitative detection method of fentanyl. According to the method, a differential pulse voltammetry (DPV) is used for making a linear relation diagram of a potassium ferricyanide peak current and fentanyl solutions with different concentrations to obtain a standard working curve, a linear equation is obtained through the standard curve, and the detection limit is 1.0 * 10 <-12 > mol.L <-1 >; the molecularly imprinted membrane modified electrode prepared by the invention is used for measuring the peak current of a potassium ferricyanide solution, so that fentanyl molecules can be indirectly and quantitatively analyzed and measured. The method is characterized in that a fentanyl molecularly imprinted membrane is electrically polymerized on the surface of a glassy carbon electrode, m-phenylenediamine is used as a functional monomer, and the selectivity and sensitivity of an electrochemical method for detecting fentanyl are improved. Meanwhile, by taking an adsorption pulse stripping voltammetry (DPASV) as a detection technology, a method capable of rapidly detecting fentanyl molecules in the presence of various drugs is established. The molecularly imprinted membrane electrode disclosed by the invention is simple to prepare, quick in response and good in selectivity and reproducibility, and can be repeatedly used for more than five times.

The invention relates to the technical field of preparation of electrochemical sensors, and particularly discloses a preparation method of a novel electrochemical enzyme sensor for profenofos pesticide detection based on an enzyme inhibition action principle, and the preparation method comprises the following steps: S1, treating a glassy carbon electrode to obtain a bare glassy carbon electrode GCE; s2, obtaining a composite material modified electrode Au50Ag2 (at) G / GCE; s3, an enzyme-chitosan composite modified electrode KbE-CS / Au50Ag2 (at) G / GCE is obtained; and S4, finally obtaining the profenofos electrochemical enzyme sensor NF / KbE-CS / Au50Ag2 (at) G / GCE based on the enzyme inhibition effect. According to the present invention, the white kidney bean esterase derived from plants is adopted as the detection enzyme source, and the electro-catalysis amplification effect of the Au50Ag2 (at) G composite material is adopted to construct the novel electrochemical enzyme sensor, and the method is the profenofos pesticide detection technology based on the enzyme inhibition effect principle;

The application relates to the field of electrochemiluminescence detection, in particular to a preparation method and a detection method of an electrochemiluminescence sensor for detecting di(2-ethylhexyl) phthalate. Technical points are as follows: the electrochemiluminescence aptamer sensor is formed by loading carboxylated ligands on the surface of a Zr-MOF / GDY composite material modified glassy carbon electrode; the Zr-MOF / GDY composite material is formed by electrostatic interaction between Zr-MOF and GDY; and the carboxylated aptamer is an aptamer containing a base sequence of 5'-GGGTAGGGCGGGAAGTTACTGTCTTACTGTC GTA-3'. The recovery effect of DEHP on the ECL signal intensity of the electrochemiluminescence aptamer sensor of the GDY and Zr-MOF composite material is used to realize the detection of DEHP, and the detection method is simple in operation, good in selectivity and high in sensitivity.

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.

The application belongs to the technical field of electrochemical analysis and detection, and discloses a preparation method and application of an electrochemiluminescence sensor for specifically detecting trilobatin. The specific operation includes: (1) preparing a composite material of nitrogen-doped carbon quantum dots (N-CDs) and a silver-based metal organic framework (AgMOF) (AgMOF@N-CDs); (2) modifying the AgMOF@N-CDs on a glassy carbon electrode to obtain AgMOF@N-CDs / GCE; and (3) based on a three-electrode system, using the AgMOF@N-CDs / GCE as a working electrode, a platinum wire as an auxiliary electrode, and Ag / AgCl as a reference electrode to construct an electrochemiluminescence sensor for detecting trilobatin. The preparation of the electrochemiluminescence sensor is simple, the analysis speed is relatively fast, the detection range is relatively wide, the sensitivity is relatively high, and the selectivity is relatively good.

The application provides a Cu-MOF@MnCO3 modified glassy carbon electrode and a preparation method thereof and an electrochemical sensor, and the preparation method comprises the following steps: S1, preparing Cu-MOF@MnCO3 powder; S2, polishing, cleaning and drying the surface of a glassy carbon electrode for standby; S3, dissolving the Cu-MOF@MnCO3 powder in DMF, dropwise coating the surface of the glassy carbon electrode treated in the step S2, and heating and drying under an infrared lamp to obtain a Cu-MOF@MnCO3 modified glassy carbon electrode. On the one hand, by combining the signal generated by mercury ions itself and the internal reference signal generated when Cu 2+ and Cu + in the Cu-MOF occur a reduction reaction, the false positive phenomenon is effectively avoided, and the anti-interference, stability and reliability of the electrochemical sensor for detecting mercury ions are improved. On the other hand, the application can further widen the detection range of the electrochemical sensor and reduce the detection limit by amplifying the double signals of MnCO3, and is particularly suitable for detecting trace mercury ions.

The invention discloses a dual-mode detection kit for highly sensitive detection of ERalpha based on HRP-streptavidin. The dual-mode detection kit comprises the following raw materials: a glassy carbon electrode, 1-AP-CNHs, AuNPs, Sh-Apt, MCH, Bio-Ab, and HRP-streptavidin. The invention successfully constructs an electrochemical detection kit for detecting ERalpha with high sensitivity on the basis of the 1-AP-CNHs / AuNPs composite material. According to the invention, due to the redox activity of HRP-streptavidin, the HRP-streptavidin and H2O2 are subjected to redox reaction to generate a current signal; in addition, hydrogen peroxide can be catalyzed to generate. OH free radicals, and the free radicals can oxidize TMB to generate blue products, so that colorimetric reaction is initiated, and ERalpha can be detected more accurately. The electrochemical-colorimetric dual mode of the 3D 1-AP-CNHs / AuNPs composite material and the HRP-streptavidin for high-sensitivity detection of the ERalpha disclosed by the invention greatly improves the detection accuracy. The kit has the advantages of good selectivity, strong stability, high sensitivity, anti-interference performance, environmental protection and the like.

The invention belongs to the technical field of food safety detection, and particularly relates to a histamine molecular imprinting electrochemical sensor based on a carbon-based nano composite material and a preparation method and application of the histamine molecular imprinting electrochemical sensor. Aiming at the problems of poor selectivity, high detection limit or complicated operation and the like of the existing histamine detection technology, a Co3O4 / N-HCS (cobaltosic oxide / nitrogen-doped hollow carbon sphere) composite material is prepared by adopting a solvothermal method, o-phenylenediamine (o-PD) is taken as a functional monomer, a molecularly imprinted polymer membrane (MIP) is constructed on the surface of a glassy carbon electrode (GCE) by adopting an electropolymerization method, and the histamine detection electrode is prepared. The MIP / Co3O4 / N-HCS / GCE sensor with specific recognition sites on histamine is formed. The sensor has high selectivity, high sensitivity and good stability, is simple and convenient to operate and rapid in detection, can efficiently realize accurate detection of histamine in food, and is suitable for safety monitoring scenes of various foods such as fermented food, aquatic products and dairy products.

The application relates to the field of electrochemistry, in particular to a method for determining ion concentration based on a double electrolytic cell ion selective electrode, which comprises the following steps: using a poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonic acid) modified glassy carbon electrode or a reduced graphene oxide modified glassy carbon electrode as a working electrode, using a full solid-state ion selective electrode as a reference electrode, and using a platinum wire electrode as a counter electrode; inserting the working electrode and the counter electrode into a test electrolytic cell, inserting the reference electrode into a sample electrolytic cell, connecting the test electrolytic cell and the sample electrolytic cell through Ag / AgCl as a salt bridge, and determining the ion concentration in a to-be-measured solution by adopting a constant potential coulomb analysis method. The technical scheme of the application can minimize the current response time while ensuring the accuracy of ion concentration determination, realizes rapid measurement of ion concentration, and can be applied to detection of ion concentration in human serum.

The invention discloses a chitosan modified ferroferric oxide / carboxylated multi-walled carbon nanotube-based molecularly imprinted electrochemical sensor as well as a preparation method and application thereof, and relates to the technical field of electrochemical sensing. The invention aims to solve the problems that the existing method for detecting carbendazim is complicated to operate and high in cost and the traditional sensor is poor in selectivity. The invention discloses a molecularly imprinted electrochemical sensor based on chitosan modified ferroferric oxide / carboxylated multi-walled carbon nanotubes. The molecularly imprinted electrochemical sensor comprises a glassy carbon electrode, and a molecularly imprinted polymer and CS-Fe3O4-CMWCNTs which are modified on the surface of the glassy carbon electrode, the molecularly imprinted polymer is prepared by taking carbendazim as a template molecule, methacrylic acid as a functional monomer, ethylene glycol dimethacrylate as a cross-linking agent and azodiisobutyronitrile as an initiator. The molecularly imprinted electrochemical sensor is applied to detection of carbendazim.

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 invention discloses a method for high-value utilization of micro mineral powder solid waste, which comprises the following steps of: naturally air-drying micro mineral powder, grinding and sieving to obtain a micro mineral powder raw material; uniformly mixing the micro mineral powder with biomass in different proportions, performing high-temperature oxygen-limited pyrolysis in a muffle furnace, and modifying by phosphoric acid, citric acid, CaCl2 and the like to obtain a micro mineral powder / biomass nano composite material; dispersing the micro mineral powder / biomass nano composite material and chitosan in water, and performing ultrasonic compounding for a period of time to obtain a chitosan / micro mineral powder / biomass nano composite material mixed solution; dispensing the mixed solution on the surface of a glassy carbon electrode to prepare a chemically modified electrode; the electrode is used for detecting dopamine and nitrite substances. The micro mineral powder nano material with high electrocatalytic activity can be prepared and can be used as an electrode material in the fields of batteries, electrochemical sensors, capacitors and the like.

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.