62 results about "Square wave voltammetry" patented technology

The invention discloses an electrochemical sensor capable of detecting trace mercury in a water body. The electrochemical sensor comprises a gold electrode, wherein gold nanoclusters are deposited on the surface of the reaction end of the gold electrode; and sulfhydryl-modified mercury-specific oligonucleotide probes are self-assembled on the gold nanoclusters. The preparation method for the electrochemical sensor comprises the following steps of: first, preparing the gold electrode; then, electrodepositing the gold nanoclusters on the surface of the reaction end of the gold electrode; and finally, self-assembling the sulfhydryl-modified mercury-specific oligonucleotide probes on the end surfaces of the gold nanoclusters so as to finish the manufacturing of the sensor. By using the sensor provided by the invention, the trace mercury in the water body can be detected; and the specific operation comprises the following steps of: first, placing the reaction end of the sensor in a water sample for reacting; then, immersing the reaction end into an anion double-stranded deoxyribonucleic acid (DNA) signal embedded agent for complete treatment; later on, connecting the sensor into an electrolytic cell of a three-electrode system and measuring the change of a response peak current by using square wave voltammetry; and finally, judging whether the water sample contains mercury ions on the basis of the change. The electrochemical sensor has the advantages of simple and practical structure, convenience in manufacturing, high sensitivity, high selection specificity and the like.

The invention discloses a manufacture method of a silver hybridization mesoporous ferroferric oxide antibiotic immunosensor and the application thereof. The manufacture method of the electrochemical immunosensor includes modifying thionine-graphene mixed solution on the surface of a glassy carbon electrode, conducting cross linking on an antibiotic antibody incubated by Ag-Fe3O4 mesoporous nanometer particles, closing non-specificity active sites by bovine serum albumin to manufacure the antibiotic electrochemical immunosensor. A detection method of antibiotic is that a reference electrode-saturated calomel electrode, an electrode-platinum filament electrode and a working electrode are correctly connected on an electrochemical working station, and immunodetection is conducted through the square wave voltammetry. The antibiotic electrochemical immunosensor has high sensitivity and selectivity, is simple in detection method and has the advantages of being quick, high in efficiency, goodin specificity, low in cost, convenient to operate and the like. It takes to 2-3 minutes to finish one detection process.

A graphene-modified graphite pencil electrode (GPE) system and a method for detecting L-tyrosine in a solution. The electrode system includes a graphene-modified graphite pencil working electrode comprising a graphite pencil base electrode and a layer of graphene comprising wrinkled graphene sheets on the surface of the graphite pencil base electrode, a counter electrode, and a reference electrode. The method comprises contacting the solution with the graphene-modified GPE system and conducting voltammetry, preferably square wave voltammetry, to detect the L-tyrosine concentration in the solution.

A graphene-modified graphite pencil electrode (GPE) system and a method for simultaneous detection of multiple anylates such as dopamine, uric acid, and L-tyrosine in a solution. The electrode system includes a graphene-modified graphite pencil working electrode comprising a graphite pencil base electrode and a layer of three dimensional nanostructured multiwall network forming concave shape structures on the surface of the graphite pencil base electrode, a counter electrode, and a reference electrode. The method comprises contacting the solution with the graphene-modified GPE system and conducting voltammetry, preferably square wave voltammetry, to detect the L-tyrosine concentration in the solution.

The invention discloses an electrochemical immunochromatographic test strip for rapid quantitative detection of a novel coronavirus antigen and a preparation method thereof. On the basis of a double-antibody sandwich immune reaction, gold platinum core-shell nanoparticles Au@PtNPs have catalytic activity similar to horse radish peroxidase, and the gold platinum core-shell nanoparticles Au@PtNPs are marked on a secondary antibody (antibody2, Ab2) to serve as an electrochemical signal probe Au@PtNPs-Ab2. The integrated electrochemical lateral flow immunochromatography test strip for rapid and quantitative detection of the human serum novel coronavirus antigen is prepared by utilizing the characteristics of rapid reaction and convenient separation of lateral flow immunochromatography. After the immune reaction, a horse radish peroxidase substrate solution is added, and a current signal generated by the Au@PtNPs-Ab2 probe captured in the detection area is measured by adopting a square wavevoltammetry (SWV), so as to realize the quantitative detection of the COVID-19 antigen. The prepared electrochemical lateral flow immunochromatography test paper based on the low-cost and high-performance Au@PtNPs-Ab2 signal probe can provide a new method for rapid, quantitative and instant detection in the aspect of diagnosis of COVID-19.

The invention provides a method for real-time monitoring rare earth ion removing of fused salt by electrochemical means. The method comprises the following steps: heating rare earth chloride containing LiCl and KC1 fused salt until the fused salt is molten; connecting a reference electrode, a working electrode and a counter electrode three-electrode system to an electrochemical workstation; addingtrisodium phosphate anhydrous to the LiCl and KCl fused salt by batches; standing for 30min after adding trisodium phosphate anhydrous each time; detecting a square wave volt-ampere curve through thereference electrode, the working electrode and the counter electrode three-electrode system; and obtaining the variation of the concentration of rare earth ions based on the peak height of a standardworking curve of rare earth chloride. According to the method, fused chlorides can be purified and recycled; the purifying rate of the rare earth ions is more than 99%; and meanwhile, the precipitation reaction progress can be monitored in real time through square wave voltammetry; the process of monitoring the variation of the concentration of the ions by the square wave voltammetry is an automatic continuous process, and the method has the characteristics of being high in sensitivity and quick to analyze by being compared with other analyzing methods.

The invention discloses a method for measuring the oxidizing metallic ions in water, pertaining to the technical field of environmental monitoring. The method is as follows: a organic solvent containing iodine after extraction is poured into a glass micropipe; then, a platinum wire is inserted into the glass micropipe of which the front end is sealed to form a platinum electrode, namely, a working electrode which is just positioned on the interface of electrolyte solution without iodine ions so as to from a liquid/ liquid interface; and after a reference electrode, an auxiliary electrode and the working electrode are all well fixed, the three electrodes are connected with an electrochemical analyzer, then electrochemical analysis is carried out by square wave voltammetry or cyclic voltammetry so as to measure the metallic ions with strong oxidizing property. As an organic solvent MIBK has low toxicity and does not dissolve in water, the characteristics of environmental harm and the like of the traditional dropping mercury electrode are overcome; in addition, the method also has the advantages of simple and convenient operation, high sensibility, low cost and being capable of carrying our measurement on the metallic ions with oxidizing property in industrial sewage.

The invention discloses a method for detecting the concentration of human epidermal growth factor receptor-2 (HER-2). The method comprises the following steps: grinding, cleaning and drying gold electrodes; inserting the gold electrodes into a polypeptide solution for carrying out self-assembly, and then closing the gold electrodes with mercapto hexanol; respectively dripping HER-2 with different concentrations onto the surfaces of the gold electrodes for carrying out reactions, and then enabling the gold electrodes to react with an aptamer; dripping molybdate onto the surfaces of the gold electrodes for carrying out reactions to obtain a plurality of to-be-detected gold electrodes; respectively measuring the gold electrodes by using a square wave voltammetry to obtain a plurality of square wave voltammetric curves, and making a standard curve according to peak currents in all the curves and the corresponding concentrations of the HER-2; dripping the HER-2 to be detected onto the surface of the gold electrode assembled with polypeptide for carrying out a reaction, then enabling the gold electrode to react with the aptamer, dripping molybdate onto the surface of the gold electrode, measuring by using the square wave voltammetry to obtain a square wave voltammetric curve, and contrasting the peak current with the standard curve to obtain the concentration of the HER-2. The detection method is convenient and fast, good in selectivity, high in sensitivity and wide in detection range.

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 relates to a method for detecting a prohibited additive acid orange II in food, comprising the following steps of: preparing a series of different concentrations of acid orange II standard storing solutions, carrying out electrochemical detection on them by a square wave voltammetry method to obtain a current value of an anodic peak, making a standard curve by using the concentration of the standard storing solutions as a horizontal ordinate and the mean current value of the anodic peak as a vertical coordinate so as to obtain a corresponding equation of linear regression, carrying out pretreatment on different samples to be measured by processes of ultrasonic extraction, centrifugation and the like, and calculating the content of acid orange II in the samples to be measured by introducing the obtained current value into the equation of linear regression corresponding to the standard curve. The method provided by the invention has advantages of low detection limit, no requirement of complex equipment, low detection cost and high sensitivity, is simple to operate, overcomes insufficiencies in the prior art, and can be widely applied in the field of food detection.

The invention provides a preparation method of a lithium ion battery cathode material composited by in-situ synthesis Fe-Fe3O4. The preparation method comprises the following steps: by taking a nano array (nanowire array such as C@TiO2, C@TiC) in a three-dimensional open structure as a base body, and a Fe salt solution as a deposited mother liquid, utilizing electrodeposition technologies of constant current, constant potential, cyclic voltammetry, pulse square wave voltammetry and the like, depositing a metallic Fe film on the base body, then placing the base body in a growth solution to carry out in-situ growth, and finally calcining in air to form the lithium ion battery cathode material composited by the Fe-Fe3O4. The preparation method can be used for preparing the lithium ion battery cathode with the high specific capacity, the high rate performance and the good cycle performance. The electrode is in a three-dimensional structure, and thus an active substance can be fully contacted with electrolyte, and the transfer of electrons/ions is effectively enhanced.

The invention relates to a method for measuring ciprofloxacin through a graphene-and-hematoxylin-integrally-modified glassy carbon electrode, and belongs to the technical field of chemical measurement and electrochemical analysis detection. According to the method, graphene is subjected to electrolytic deposition, then the glassy carbon electrode modified by hematoxylin is subjected to electrochemical polymerization, and an even compounded modified film is formed in the surface of the electrode accordingly so that the stability and the sensitivity of the electrode can be improved. The sensitivity of the ciprofloxacin is subjected to quantitative analysis measurement with the square wave voltammetry and the current-time technology; the experimental result shows that in a 0.10-mol/L phosphoric acid buffering solution with pH equal to 3.0, the modified electrode has the obvious catalysis and sensitization effects on the ciprofloxacin; under the optimum condition, the current-time technology method is adopted for measurement, the ciprofloxacin and a peak current of the ciprofloxacin have the good linear relationship from 0.5 micron to 45.0 microns, and the detection limit is 0.20 micron. The method can be directly used for rapid electrochemical measurement of the ciprofloxacin, and has the advantages of being rapid, sensitive, accurate and the like.

The invention provides a metronidazole detection method and belongs to the technical field of metronidazole. The method includes: adopting a mode of dropwise smearing amino functionization MCM-41 on a glass carbon electrode to prepare an amino functionalization MCM-41 modified electrode; utilizing a three-electrode system, and adopting a square wave voltammetry to detect metronidazole. A result shows that amino functionalization MCM-41 modified electrode differential pulse voltammetry is adopted to detect metronidazole different in concentration, peak current is constantly increased along with increase of concentration of a metronidazole solution, the peak current of metronidazole presents good linear relation with the concentration of metronidazole, and correlation coefficient is 0.9974. Detection limit of the method is 1.7x10-7mol/L; comparison tests show that the peak current of metronidazole on the amino functionalization MCM-41 modified electrode is obviously higher than those on an MCM-41 modified electrode and a naked glass carbon electrode. The metronidazole detection method has the advantages of high sensitivity, simplicity and convenience in operation, quickness, low instrument cost and easiness in realizing automation.

The invention relates to a method for preparing electrochemical sensors, and particularly relates to the preparation of novel electrodes based on gold nanoparticles. In a sensor provided by the invention, due to the modification of the gold nanoparticles, the surface area and porosity of an electrode are greatly increased, and an electrochemical detection method based on the gold nanoparticle modified carbon paste electrode provides a novel, simple, good-selectivity and quickly-responded method for detecting vitamins B in plasma of a human body. The invention provides a reliable, simple, rapid, selective and high-sensitivity method for detecting vitamins B by using the square wave voltammetry.

The invention relates to a method for electrochemically measuring the content of hydroperoxides in emulsion. The method comprises the following steps of: (1), dropping and coating a potassium ferrocyanide solution and a PVA (Polyvinyl Alcohol) solution on the surface of a processed glassy carbon electrode, and drying and placing the glassy carbon electrode, for future use; (2), adding the emulsion to be detected into an extracting solvent to obtain an emulsion extract; and (3), diluting by adding the extract in the step (2) into a supporting electrolyte solution, adding a diluent into an electrolytic tank, inserting a three-electrode system that a working electrode is a modified electrode, a counter electrode is a platinum gauze electrode and a reference electrode is a saturated calomel electrode, and measuring the content of the hydroperoxides in the electrolytic tank by utilizing a square wave voltammetry. The method disclosed by the invention is used for preparing a highly sensitive modified electrode at first and then extracting the hydroperoxides in the emulsion effectively, thus, rapid and accurate measurement by using the electrochemical square wave voltammetry is realized.

The invention discloses a microelectrode-based tumor marker rapid high-sensitivity detection method, wherein a tumor marker is a CEA. The detection method comprises the following steps of synthesizing a CEA aptamer and modifying the tail end of the CEA aptamer with sulfydryl, manufacturing a bare electrode, depositing gold nanoparticles on the surface of the bare electrode, then combining the gold nanoparticles with the sulfydryl-modified CEA aptamer, drawing a standard curve, detecting a clinical sample, and determining the content of CEA in a sample according to the standard curve. The method has the beneficial effects that (1) the microelectrode is used as a current type sensor, so that the rapid and high-sensitivity detection of the tumor marker in a small-volume serum sample can be realized; (2) the aptamer is used as a specific recognition molecule, the synthesis is simple, the stability is good, the affinity is strong, and the selectivity is high; and (3) electrochemical detection based on square wave voltammetry is low in cost, is simple and convenient to operate and is rapid in detection.

The invention provides a gas-phase nicotine electrochemical determination method based on a passive sampling method, which comprises the following steps: selecting a silk-screen printing gold electrode, adopting a sulfuric acid solution to electrochemically preprocessing an electrode, selecting a handheld portable electrochemical workstation to construct a portable nicotine electrochemical sensor, and connecting a gas-phase passive sampler and an electrochemical detection device for use; placing the device in a closed box, exposing the device in flue gas environments with different concentrations, and performing detecting in a voltage range of 0.5-0.9 V by adopting a square wave voltammetry to obtain a characteristic response current value of nicotine; detecting the actual tobacco sample according to the method, obtaining the nicotine response current value, substituting the response current value into the standard curve and the corresponding linear regression equation, and obtaining the concentration of nicotine in the sample. The method is easy and convenient to operate and low in detection cost, tedious sample pretreatment and separation are not needed, and direct detection of nicotine is achieved. The abstract drawing is a schematic diagram for detecting nicotine.

Method and system for detecting and/or quantifying Δ⁹-tetrahydrocannibinol (THC) in a saliva sample. In one embodiment, the method involves providing an electrochemical sensing element, the electrochemical sensing element including a working electrode, a counter electrode, and a reference electrode, all of which are screen-printed. A saliva sample is then deposited directly on the working electrode. Next, the deposited saliva sample is treated with a fluid that includes one or more alcohols and water in an alcohol/water ratio of 50/50 to 100/0 (v/v), the fluid optionally also including a surfactant. Next, the treated saliva sample is dried, whereby any THC present in the treated saliva sample is immobilized on the working electrode. Next, an electrolytic solution is delivered to the electrochemical sensing element, and the THC immobilized on the working electrode is directly electrochemically detected and/or quantified using a pulse voltammetry technique, such as square-wave voltammetry.

The invention relates to cyclic square wave voltammetry for detecting vitamin content in a blood sample. The invention belongs to the technical field of vitamin analysis and detection. The cyclic square wave voltammetry for detecting vitamin content in a blood sample is characterized by mixing a blood sample to be measured with a vitamin sample treatment fluid, detecting current signals generated by the sample in an oxidation reduction reaction on the sensor probe of a vitamin detector, formulating a standard curve based on a comparison of current signal values of vitamin standard samples with different concentration, and obtaining the vitamin content in the blood sample to be measured based on current signal values generated by the sample. The invention has the advantages of high sensitivity, good accuracy, simple operation, a high speed and a wide application scope; therefore, the invention is applicable to medical departments, and can be used for the analysis and detection of vitamin A, B1, B2, B6, B9, B12, C, D, E, K1 and K3 and for a rapid detection of vitamin content in a blood sample.

An electrochemical method is provided, whereby electrodes are coated with conductive diamond film material. The method detects the concentration of metal ions and organic compounds in solutions by using square wave voltammetry of pulsed voltammetry. Since the electrodes coated with conductive diamond film material enable the user to obtain broader range of voltage measurement, the number of chemicals detected is greatly increased and the accuracy thereof improved.

The invention provides a method for detecting the concentration of acrylamide in a solution, the method comprises the steps of using a three-electrode system to detect the acrylamide in the solution to be detected through a square wave voltammetry, obtaining the concentration of the acrylamide in the solution to be detected according to the linear equation of acrylamide, wherein the working electrode in the three-electrode system is a gold electrode which is modified by characteristic single-stranded DNA, and the DNA sequence is 5minute-AAAAAAAAA GGAAAAAAAAA-(CH2) 6-SH-3minute. According to the method provided by the invention, the square wave voltammetry is utilized for high sensitivity detection of the acrylamide, the detection limit of acrylamide concentration can reach 1mo1/L, the method is simple in operation, quick in detection, high in sensitivity and good in selectivity, and has a broad application prospect.

The invention discloses a port porcine epidemic diarrhea virus electrochemical detection method based on silver deposition signal amplification, and belongs to the technical field of life science. The detection principle is as follows: a biotin-modified porcine epidemic diarrhea virus PEDV probe 1 is fixed on the surface of a streptavidin-modified magnetic bead to form a capture element 1, namely MBs-probe1, a sulfydryl SH-modified PEDV probe 2 is fixed on the surface of a gold nanoparticle to form a capture element 2, namely AuNPs-probe2, and when a screened PEDVN gene conserved sequence exists, the capture element 1, namely MBs-probe1, and the capture element 2, namely AuNPs-probe2, is fixed on the surface of the magnetic bead; the two sections of capture elements are hybridized with the conserved sequence of the PDEVN gene to form an MBs-probe1/AuNPs-probe2/PEDV complex; the complex is cut by using the characteristic that exonuclease III cuts the sunken tail end of double-chain DNA 3 ', a signal element AuNPs-probe4 is collected through magnetic separation, then the collected signal element is dropwise added to the surface of a silk-screen printing electrode which is plated with gold on the surface and is covalently modified with a nucleic acid probe probe3, and signal amplification is performed by using silver deposition. And finally, the current intensity measured by square wave voltammetry (SWV) is positively correlated with the PEDV concentration.

The invention relates to a square wave voltammetry battery sorting method and device. The device comprises an intelligent controller (1), a constant potential rectifier (2), a measured battery (3), a current sensor (4) and a sampling/retaining appliance (5). The invention simultaneously provides the square wave voltammetry battery sorting method. The square wave voltammetry battery sorting method is characterized in that a measurement process is circularly composed of a series of small steps, a delta Ep forward direction electric potential with one pulse height is applied on the battery and can keep constant in each circulation, the current sampling is preformed after special time t, a delta Ep negative direction electric potential with one pulse height is applied on the battery and can keep constant, the current sampling is preformed after special time t, then the potential changes a small range delta Es, the next circulation begins, a changing curve of the current to the voltage in the whole circulating process is recorded, and same batteries are marked in the same kind according to the changing curve.