78 results about "Chemically modified electrode" patented technology

The invention discloses a method for preparing graphene oxide/carbon nano tube/cellulose composite gel from ionic liquid, relating to a preparation method of cellulose composite gel and aiming to solve the technical problems that the composite gel obtained by using the traditional method is polluted by a solvent and the gel is easy to deform in a solvent exchange process. The method comprises the following steps of dissolving cellulose into ionic liquid; then, adding graphene oxide and carbon nano tube dispersing liquid; pouring a mixed solution obtained after reacting under heating into a die; standing for cooling; then, replacing the ionic liquid by using water; next, drying to obtain the graphene oxide/carbon nano tube/cellulose composite gel. The graphene oxide/carbon nano tube/cellulose composite gel can be used for a sensor, an electromagnetic shielding material, a chemically modified electrode or a supercapacitor.

The present invention provides an electrochemical detection method for content of glycosylated hemoglobin in the blood, and is characterized in that: whole blood specimen is diluted by combined liquid ranging from 30 times to 70 times and passes through a glycosylated protein recognizer, electric activated small molecules are filled into the effluent liquid from the glycosylated protein recognizer, and electrochemical response of the liquid is detected by chemically modified electrodes after the filling, thereby obtaining the concentration of the blood glucose. The glycosylated protein recognizer is eluted by elute solvent, and the electrochemical response of the elute solvent is detected and the concentration of the glycosylated hemoglobin is obtained, thereby obtaining the content of the glycosylated hemoglobin of the sample after calculation. As the electrochemical detection is simple in operation, lower in cost and rapid in the analysis, the present invention is expected to realize the rapid determination of the clinical glycosylated hemoglobin and the rapid determination of the glycosylated hemoglobin after separation and elution.

The invention relates to an electro-polymerizable chemically-modified electrode organic material and application of the electrode organic material in ultra-trace TNT (Trinitrotoluene) detection and belongs to the field of electrochemical sensing technologies. The structural formula of the organic material is shown in the specification, wherein the molecular main chain skeleton consists of an A and two side units B. The A can be pyrene, naphthalene, anthracene, an anthracene derivative, phenanthrene, dibenzo-quinoxaline or the like; each B can be benzene, biphenyl, phenylene vinylene, fluorene or the like; each unit C is an electro-active unit and can be furan, pyrrole, thiophene, carbazole, diphenylamine, triphenylamine or the like. A connecting chain R for the molecular main chain skeleton and electrochemically-polymerized groups can be an alkyl chain, alkoxy chain or oxy chain. Carbazolyl groups can be subjected to crosslinking during electrochemical polymerization, and molecules can form spherical micro-nano structures due to crosslinking, so that on one hand, the contact specific surface area between the molecules of the organic material and TNT molecules is increased, on the other hand, due to pore structures formed among the micro-nano structures, TNT molecule diffusion paths are increased, and electrical signal response is enhanced.

The invention discloses a catalyst for catalyzing methyl alcohol. The catalyst disclosed by the invention comprises graphene, a polyacrylic acid-ferrocene compound and metal nanoparticles, wherein the mass ratio of the grapheme to the polyacrylic acid-ferrocene compound and the metal nanoparticles is (20-50):(150-250):(1-15). The graphene is taken as a substrate material of the catalyst for catalyzing methyl alcohol disclosed by the invention; the polyacrylic acid-ferrocene compound can enter a layer structure of the graphene to inhibit the aggregation of the graphene; homogeneous nucleation of the metal nanoparticles is promoted by the polyacrylic acid, so that the loaded metal nanoparticles has a higher catalytic activity; due to a net structure of the polyacrylic acid, the graphene-polyacrylic acid-ferrocene has a multi-channel stereoscopic structure, the movement of the particles is buffered and the homogeneous growth of the metal nanoparticles is further promoted. Therefore, the catalyst for catalyzing methyl alcohol disclosed by the invention has the advantages of higher catalytic activity for methanol and higher capability of resisting the poisoning of an intermediate.

The invention belongs to the technical field of biochemical sensing, and discloses a semiconductor sensor for virus detection as well as a preparation method and an application thereof. The preparation method comprises the steps of (1) preparing an oxide or chalcogenide colloid semiconductor nano-material; (2) coating the surface of the colloid semiconductor nano material with a virus specific antigen or antibody to obtain a sensitive material; and (3) based on the sensitive material, preparing the virus detection sensor by adopting device structures such as a chemically modified electrode ora field effect transistor. The virus specific antigen or antibody is introduced to the surface of the colloid semiconductor nano material, charge transfer caused by a specific binding reaction betweenthe virus antigen and antibody is converted into a sensor electric signal to be output through a semiconductor sensitive effect, and the real-time performance and convenience of a virus detection technology are improved.

The invention relates to and belongs to a potentiometric chemical sensor, in particular to a timolol maleate potentiometric chemical sensor and a preparation method thereof. The preparation method comprises the following steps: (1) carrying out the chemical modification by the periodic scanning electro-polymerization method after pre-processing the surface of the matrix electrode to prepare the chemically modified electrode; (2) preparing a PVC-film sensitive solution by the conventional method with the solvent being tetrahydrofuran, and coating the modified electrode with the PVC sensitive film by the dip-coating method to prepare a chemical sensor (I); (3) preparing the molecularly imprinted polymer (Polymer A) of timolol maleate, and preparing the PVC film (Film II) containing Polymer A; and (4) compounding the Film II onto the PVC sensitive film of the chemical sensor I. The invention can effectively overcome the disadvantages of the existence of internal reference solution electrodes in the prior art, furthermore, the chemical sensor of the invention is significantly superior to the existing ion-selective electrodes in term of the selectivity of the drug (such as propranolol hydrochloride and the like) ions with the molecule with the structures, such as alcohol amine, imido and the like.

The invention discloses a production method of a chemically modified electrode for detecting concentration of ascorbic acid. By electrochemical activity of a metal organic framework material Zn-MOFs, the Zn-MOFs/glassy carbon electrode is produced according to an electro-deposition method. The modified glassy carbon electrode can be applied to detection of the concentration of the ascorbic acid in samples.

The invention provides a graphene composite which comprises a graphene layer, a prussian blue layer arranged on the graphene layer and nano platinum particles arranged on the prussian blue layer. In the graphene composite, existence of prussian blue enables the nano platinum particles deposited on the prussian blue surface to have a small average particle size so as to give a larger active surface area to a catalyst; moreover, the characteristics of a prussian blue complex are also beneficial for enhancing interaction between Pt and graphene and reducing fall-off of the catalyst on the surface of an electrode so as to improve catalytic stability of the catalyst; furthermore, strong interaction exists between iron ions at the center of the prussian blue and CO, so that toxic adsorption of CO to the Pt catalyst can be reduced to a certain degree and the desorption oxidation process of CO is promoted, and thus, toxicity resistance of the catalyst is obviously improved. Therefore, the graphene composite provided by the invention has higher catalytic activity on catalytic oxidation on methanol and a stronger antitoxic effect.

The invention discloses application of graphite conductive adhesive to prepare a chemically modified electrode or biosensor electrode binder for electrochemical biological sensing detection, wherein, the graphite conductive adhesive comprises the following components by weight percent: 40-60% of an epoxy resin, 20-40% of graphite powder, 10-30% of a diluent and 1.5-3% of an amine curing agent. The graphite conductive adhesive has excellent electrical conductivity, excellent adhesiveness, wide and flat electrochemical window, convenient use, and excellent application prospect in electrochemical biological detection.

Provided is a preparation method of a copper oxidechemically modified electrode for detecting glucose. The method comprises the main steps that according to the mass ratio of copper ions to urea 3:2, a copper salt solution is slowly and dropwise added to the urea solution to generate a cupper ion complex having high coordination number; then, the complex is put in a hydrothermal reaction kettle to perform hydrothermal reaction, and a copper oxide precursor is prepared; the precursor is decomposed into rice-shaped copper oxide at high temperature; then the copper oxide is matched with a Nafion solution to obtain a rice-shaped copper oxide modifying solution; finally the solution is dropwise added to the surface of the solid electrode to obtain the rice-shaped copper oxidechemically modified electrode. The preparation method is simple in operation, a template agent and template are omitted, and the copper oxide having a unique rice-shaped structure can be obtained. The prepared chemically modified electrode has the good electrochemical responsiveness to glucose, low detection limit (0.000075 mM), a wide detection range (0.001-2.361mM) and high sensitivity (2.376Ma.mM-1.cm-2).

The invention discloses a rapid screening method for lead, arsenic and mercury in cosmetics. The rapid screening method comprises the simultaneous and rapid screening of lead and mercury or the simultaneous and rapid screening of arsenic and mercury and comprises the following steps of: taking the cosmetics to be detected, dissolving the cosmetics in a HCl solution, and obtaining a sample solution; taking a chemical modified electrode as a working electrode, taking a Ag/AgCl electrode as a reference electrode, carrying out stripping voltammetry detection on the sample solution, and recording data; and judging whether the lead or the arsenic or the mercury in the cosmetics to be detected is overproof according to the spike potentials and the peak currents of the lead and the mercury or the arsenic and the mercury in the sample solution. The rapid screening method disclosed by the invention is high in accuracy and high in sensitivity, the detection limits of the lead, the arsenic and the mercury are respectively 100 ppb, 25 ppb and 2.5ppb, and thus, the technical requirements on on-site rapid screening can be ensured; and the rapid screening method is simple and convenient in operation, the time and the cost for supervision can be greatly saved, and the supervision efficiency is increased.

The invention relates to the technical field of electrochemical detection and discloses a chemically modified electrode for detecting cefalexin and an electrochemical measurement method for the cefalexin. The chemically modified electrode is prepared through steps that adding colloidal gold solution to a clean gold electrode surface, drying, soaking in hydrochloric acid solution with cysteine, self-assembling at 1 to 6 degrees centigrade, taking out, and using water to wash to clean. The electrochemical detection method includes steps that adding copper sulfate solution to sample solution to be measured, hydrolyzing to obtain hydrolysate, using the chemically modified electrode as a working electrode, and using a square wave voltammetry to measure the concentration of surplus copper ions in the hydrolysate to indirectly measure the content of the cefalexin in the sample. The chemically modified electrode is high in sensitivity, fast, convenient, low in cost and the like for measuring the cefalexin.

The invention provides a preparation method of a polymer composite material. Graphene oxide, polyacrylic acid and a copper salt are taken as starting raw materials, and the polymer composite material comprises copper nano-particles, the polyacrylic acid and graphene; and the weight ratio of the copper nano-particles to the polyacrylic acid to the graphene oxide is (0.5-8): (1-10): (0.01-0.1). In the preparation method provided by the invention, the graphene oxide can be better dispersed under the action of bifunctional molecules of the polyacrylic acid, so that the agglomeration problem of a graphene solution can be solved; furthermore, more copper nano-particles can be riveted on the surface of the graphene, so that the catalytic action of the polymer composite material is improved; and in addition, the obtained graphene has higher electro-catalytic action and electron conduction performance, so that the polymer composite material provided by the invention has higher electro-catalytic performance, can be used as a modification layer to prepare a modified electrode, can be used for electro-chemical determination of glucose, and improves the sensitivity in detection of the glucose.

The invention relates to the field of nano electrochemical sensors and particularly discloses a high-sensitivity chemically modified electrode for detecting thiabendazole and a preparation method of the chemically modified electrode. The modified electrode is an ionic liquid carbon paste electrode modified with a CuO@SiO2@Ag nano-composite. The modified electrode has high measurement sensitivity and good selectivity for thiabendazole and is convenient, cheap, good in stability and suitable for on-site detection. The modified electrode is the ionic liquid carbon paste electrode modified with the CuO@SiO2@Ag with high electrochemical activity. The prepared chemically modified electrode is successfully applied to accurate detection of thiabendazole in samples.

The invention relates to the technical field of electrochemical detection, and in particular relates to an electrochemical sensor for detecting tyrosine as well as a preparation method and application thereof. The electrochemical sensor adopts a chemically modified electrode for detecting the tyrosine as a working electrode, Ag-AgCl as a reference electrode, and a platinum wire electrode as an auxiliary electrode. An electrode test system is connected with an electrochemical working station to form the electrochemical sensor for detecting the tyrosine after the electrode test system is assembled by utilizing a three-electrode method. The chemically modified electrode or the electrochemical sensor for quantitatively detecting the tyrosine has extremely low detection limit and a wider detection range as well as good stability, anti-interference ability and reproducibility.

The invention provides an electrochemiluminescence method for detecting catechol, and belongs to the field of catechol detection. The operation process includes the following steps of: (1) preparing acopper-based metal organic framework (MOFs) HKUST-1 composite material doped with carbon dots (CDs); (2) preparing a CDs@HKUST-1/GC chemically modified electrode; (3) forming a traditional three-electrode system by taking the CDs@HKUST-1/GC modified electrode as a working electrode, taking an Ag/AgCl electrode as a reference electrode, and taking a platinum electrode as an auxiliary electrode, and detecting catechol by using the electrochemiluminescence method. The modified electrode CDs@HKUST-1/GC has a simple preparation method, has high sensitivity to the detection of catechol, and realizes a wide linear range. According to the scheme of the invention, the detection range is 5.0*10-9mol/L to 2.5*10-5mol/L, and the minimum detection limit is 3.8*10-9mol/L.

The invention discloses a chemically modified electrode, preparation of the chemically modified electrode and a method for rapid determination of acid value of plant oil, which belong to the technical field of the rapid determination of the acid value of the plant oil. The chemically modified electrode is a platinum electrode modified by perchlorate ion-doped polypyrrole. Electro-polymerization is carried at an electrochemical working station by adopting constant potential and circular scanning technology, so that a perchlorate ion-doped pyrrole polymer is formed on the surface of the platinum electrode. Pyrrole monomers are polymerized on the electrode by an electro-chemical method and doped with ions at the same time to ensure that the electrode has a catalytic effect on a reduction reaction of unsaturated fatty acids and conducts a current of the reaction simultaneously, so that the acid value of the plant oil can be calculated according to the value of the current. The modified platinum electrode prepared by the electro-polymerization by adopting the constant potential and circular scanning technology has high stability and high repeatability; and when the method is used for determining the acid value of the plant oil, the color and luster or the turbidity of an oil sample exert no interference with the determination of a voltammetric current, the required amount of the oil sample is relatively small, and the sensitivity and the accuracy are superior to those of the traditional titration and the potentiometric titration.

The invention relates to the field of cyclic voltammetry analysis and chemically modified electrodes, and in particular relates to an electrode manufacturing and electrochemical analytical method for measuring the content of adenine in Maca. The method comprises the following step of an electrochemical sensor capable of being used for measuring the content of adenine in Maca by successively using o-phenylenediamine, beta-cyclodextrin and silver-carbon nano tube modified glassy carbon electrodes. The critical characteristic of the method provided by the invention is as follows: the method comprises the steps: adding a carbon nanotube into an AgNO3 solution; and then putting the modified glassy carbon electrode therein and scanning the same in an electrochemical condition. The result represents that the electrochemical effect of the modified electrode on adenine is obvious. The method is sensitive, simple and good in repeatability. By applying the method, the content of adenine in Maca can be accurately measured. Compared with a conventional method of measuring adenine, the method provided by the invention is simple to operate, low in measuring cost and easy to operate. The method also can be applied to measuring the content of active ingredients of other adenine drugs.

The invention discloses a method for preparing a graphene chemically modified electrode through in-situ growth, which mainly comprises the following steps: (A) substrate cleaning; (B) in-situ growth of graphene: placing the substrate obtained by the step (A) in a clean quartz boat, and placing the quartz boat in a quartz tube of a horizontal resistance furnace; introducing argon to remove oxygen in the quartz tube; under the protection of the argon, heating the quartz tube to the growth temperature of graphene; preserving heat for 1-180 minutes while introducing carbon source gas and hydrogen instead; then, cooling to room temperature under the protection of argon, and taking out a product to obtain a substrate with in-situ grown graphene; (C) connecting the substrate with graphene of in-situ growth, obtained by the step (B), with a wire or directly putting the substrate into a clamp to obtain the graphene chemically modified electrode. The preparation process of the method is simple, the preparation efficiency is high, and the method is suitable for large-scale production; the prepared graphene chemically modified electrode has good quality and excellent detection performance.

The invention discloses a silver-Prussian-blue-loaded nitrogen-doped graphene composite material and a preparation method and application thereof. The preparation method comprises the following stepsof adding concentrated hydrochloric acid, deionized water and N-N-dimethylformamide into K3[Fe(CN)6] for a reaction in a reaction kettle to obtain Prussian blue; dispersing the Prussian blue in deionized water, adding glucose, and stirring the mixture to obtain a Prussian blue dispersion; adding a silver ammonia solution into the Prussian blue dispersion, heating the mixture through a water bath,and performing standing; separating and washing products to obtain a silver-Prussian blue material; adding the silver-Prussian blue material into N,N-dimethylformamide-dispersed nitrogen-doped graphene to obtain the silver-Prussian-blue-loaded nitrogen-doped graphene composite material. A chemically modified electrode prepared from the silver-Prussian-blue-loaded nitrogen-doped graphene compositematerial can be used for quickly detecting sodium nitrite in food and has the advantages of wide detection range, low detection limit, simple operation and the like.

The invention relates to a method for detecting mercury ions based on a Silica/chitosan/Ru nanoparticle electrochemiluminescence method. The method comprises the steps that silicon dioxide composite nanoparticles doped with chitosan and ruthenium are synthesized; 2, a blank Silica/chitosan/Ru-ssDNA system is prepared; 3, a Silica/chitosan/Ru-DNA/Hg system is prepared; 4, a modified electrode is assembled; 5, electrochemiluminescence signals are detected; 6, a delta Ii-CHgi standard curve is built; 7, detection is carried out. No complex probe molecule mark or fixing process is needed, time is saved, the cost is low, and recognition carried out by DNA rich in T basic group on mercury ions is not affected; meanwhile, the chemically modified electrode, the nanoparticle enrichment technology and an electrochemiluminescence analysis technology are combined, so that high-sensitivity Hg2+ detection is achieved, and the detection limit reaches 3pM.

The invention belongs to the electrochemical field, and particularly relates to preparation and detection methods for a chemically modified electrode for selectively measuring dopamine. The preparation comprises the following steps: preparing a multi-walled carbon nano-tube suspension, pre-treating a glassy carbon electrode, dripping and coating the prepared multi-walled carbon nano-tube suspension on the electrode, and drying for later use, soaking the electrode in 4-(2-pyridyl-azo) resorcinol solution, taking phosphate buffer as base solution, and carrying out cyclic scanning in a potential range from minus 0.8 to 2.2V to prepare the multi-walled carbon nano-tube-poly 4-(2-pyridyl-azo) resorcinol membrane modified electrode. The electrode is used for detecting the dopamine under the co-existence of ascorbic acid and uric acid, the result indicates that the electrode is capable of dividing the oxidation peak of ascorbic acid, dopamine and uric acid into three independent peaks with large distance, so that the interference of the co-existent ascorbic acid and uric acid on detection of the dopamine can be eliminated; the preparation and detection methods are high in sensitivity and good in reproducibility and stability.

The invention belongs to the technical field of heavy metal ion detection, and discloses a chemically modified electrode array sensor for detecting heavy metal ions in a water body. The sensor is characterized by comprising a counter electrode, a reference electrode and a plurality of working electrodes, wherein on a working electrode array formed by the plurality of working electrodes, differentworking electrodes are modified with different electrode modification materials, and a three-electrode system can be formed among the counter electrode, the reference electrode and any one of the working electrodes; the sensor can detect various heavy metal ions at the same time through the selectivity of different electrode modification materials to the heavy metal ions. According to the invention, the structure and arrangement mode of the key components of the sensor are improved, the plurality of working electrodes are arranged, and different functional materials are modified on different working electrodes to obtain the chemically modified array electrodes, so that various heavy metal ions in a water body can be monitored at the same time, and good detection precision is achieved.