51 results about "Tetramethyl benzidine" patented technology

The invention discloses a method for constructing a dual-mode sensor through smartphone-assisted surface molecular imprinting for detecting diphenyl phosphate and application of the dual-mode sensor, and belongs to the technical fields of biochemical analysis, functional nano materials and life science. In synthesis, solubility and selectivity of a target object and photo-initiation efficiency in a polymerization process are optimized, and diphenyl phosphate molecularly imprinted nano-enzyme MIPs is rapidly prepared through a molecular imprinting technology; in the detection, H2O2 and 3, 3, 5, 5-tetramethyl benzidine TMB are catalyzed by peroxidase-like activity of Fe and N-CDs to generate a chromogenic reaction and an inner filter effect of oxTMB is used for inhibiting a fluorescence signal, dual-signal cross validation is realized in cooperation with a smart phone, and the colorimetric-fluorescence sensor for detecting diphenyl phosphate is constructed. The sensor has specific recognition selectivity and binding affinity of diphenyl phosphate, is simple to operate and low in cost, can realize sensitive detection of diphenyl phosphate in a wide linear range, has the detection limit as low as 16 pg / mL, and is suitable for field analysis of trace DPhP in a complex water environment.

The invention discloses a method for detecting glucose on the basis of cascade catalysis of cerium dioxide / gold nano cluster-Prussian blue nano enzyme (AuNCs-CeO-HMPB). The material is prepared by compounding cerium dioxide (CeO) with similar glucose oxidase activity and hollow Prussian blue nanoparticles (AuNCs-HMPB) modified by gold nanoclusters with similar peroxidase activity through a hydrothermal assembly method. In the presence of glucose, CeO catalyzes oxidation of glucose to generate gluconic acid and H2O2, then AuNCs-HMPB synergistically catalyzes decomposition of newly generated H2O2 to generate high active oxygen species, further a colorless 3, 3 ', 5, 5'-tetramethyl benzidine (TMB) color developing agent is oxidized to generate obvious color change, and based on the cascade catalytic reaction, the enzyme-free glucose colorimetric sensor is successfully constructed. The sensor shows excellent detection performance on glucose under optimized conditions (pH = 4.0, 50 DEG C), the linear detection range is 10.00-90.00 [mu] mol / L, and the detection limit is 2.1 [mu] mol / L (S / N = 3).

The invention discloses a method for detecting aflatoxin B1 in coffee based on colorimetric and photo-thermal dual modes of MXene (at) Pt nano-enzyme, which comprises the following steps: etching Ti3AlC2 by using LiF and HCl to obtain MXene, synthesizing platinum nano-particle modified MXene nano-enzyme (MXene (at) Pt) by using dopamine carbon dots and sodium borohydride as reducing agents and adopting an in-situ reduction technology, and detecting aflatoxin B1 in coffee by using the MXene (at) Pt nano-enzyme (MXene (at) Pt nano-enzyme (MXene (at) Pt nano-enzyme (MXene (at) Pt nano-enzyme (MXene (at) Pt). The MXene (at) Pt shows near-infrared light stimulation enhanced peroxidase-like activity and photo-thermal performance and can catalyze blue deepening and temperature rising of a substrate 3, 3 ', 5, 5'-tetramethyl benzidine (TMB), when aflatoxin B1 exists, POD-like activity of MXene (at) Pt nano-enzyme is inhibited, and colorimetric and temperature signals are reduced; a method for detecting the AFB1 by the colorimetric temperature dual-mode sensor is established, and the method has the characteristics of high sensitivity, strong specificity, simplicity and rapidness in operation and the like.

The invention discloses a nano-enzyme-SERS (Surface Enhanced Raman Scattering) bifunctional sensor for detecting colorectal cancer markers with high sensitivity as well as a preparation method and application of the nano-enzyme-SERS bifunctional sensor. The preparation method comprises the following steps: coating a layer of platinum (Pt) on the surface of gold nanoparticles (AuNPs) by utilizing a chemical reduction method so as to form gold-platinum nanoparticles (Au (at) Pt NPs); assembling the synthesized Au (at) Pt NPs into an aminated capillary tube through electrostatic adsorption, so as to prepare a capillary tube SERS (Surface Enhanced Raman Scattering) substrate; the surface of Au (at) Pt NPs is modified with a marker aptamer through an Au-S bond, and the nano enzyme-SERS dual-function sensor is prepared. In the presence of hydrogen peroxide (H2O2), the Au (at) Pt NPs can catalyze the oxidation of 3, 3 ', 5, 5'-tetramethyl benzidine (TMB) to generate oxidized TMB (oxTMB) with a strong SERS (Surface Enhanced Raman Scattering) signal. When Hcy exists, the reductive sulfydryl of Hcy consumes hydroxyl free radicals (. OH) generated by H2O2 decomposition, so that TMB oxidation is inhibited, and SERS signal intensity is weakened. A linear regression equation of the logarithm of the Hcy concentration and the signal intensity is drawn according to the SERS signal intensity, so that quantitative detection of the Hcy is realized.

The invention provides a high-entropy nano enzyme. The chemical formula of the high-entropy nano enzyme is Mn < 0.4 > Co < 0.4 > Ni < 0.4 > Cu < 0.4 > Zn < 0.4 > Fe < 2.0 >) O. The invention also provides a preparation method of the high-entropy nano-enzyme, which comprises the following steps: dissolving manganese nitrate tetrahydrate, cobalt nitrate hexahydrate, nickel nitrate hexahydrate, copper nitrate trihydrate, zinc nitrate hexahydrate and sodium citrate in deionized water to prepare a clear solution A; dissolving potassium ferricyanide in deionized water to prepare a clear solution B; directly pouring the solution B into the solution A, stirring, standing and aging the obtained mixed solution at room temperature, and centrifugally collecting a product; and calcining the sample powder in a muffle furnace to obtain the high-entropy nano-enzyme. The invention further provides a catalyst which is composed of the high-entropy nano enzyme, 3, 3 ', 5, 5'-tetramethyl benzidine and H2O2. The invention also provides a method for detecting reduced glutathione by using the microfluidic paper chip analysis device. The invention provides a new normal form for constructing a multifunctional biosensing and environment monitoring platform.

This invention discloses a method and application for constructing a dual-mode sensor for detecting diphenyl phosphate using smartphone-assisted surface molecular imprinting, belonging to the fields of biochemical analysis, functional nanomaterials, and life science technology. In the synthesis process, the solubility, selectivity, and photoinitiation efficiency of the target analyte during polymerization are optimized, and molecularly imprinted nanozymes (MIPs) for diphenyl phosphate are rapidly prepared using molecular imprinting technology. In the detection process, the peroxidase-like activity of Fe,N-CDs catalyzes the colorimetric reaction between H₂O₂ and 3,3,5,5-tetramethylbenzidine (TMB), and the internal filtering effect of oxTMB suppresses the fluorescence signal. Combined with a smartphone, dual-signal cross-validation is achieved, constructing a colorimetric-fluorescence sensor for detecting diphenyl phosphate. This sensor exhibits specific recognition selectivity and binding affinity for diphenyl phosphate, is simple to operate, and low in cost. It can achieve sensitive detection of diphenyl phosphate over a wide linear range, with a detection limit as low as 16 pg / mL, making it suitable for on-site analysis of trace DPH in complex aquatic environments.

This invention discloses Ni-Fc MOF nanomaterials as Hg 2+ The application of the detection probe, the preparation method of the Ni-Fc MOF nanomaterial includes: 1,1-ferrocene dicarboxylic acid and water-soluble Ni at 110–130 °C. 2+ The Ni-Fc MOF nanomaterials were prepared by salt reaction. This invention is based on Hg... 2+ Sensitive and selective activation of oxidase activity by probes from flower-shaped Ni-Fc MOF nanomaterials was achieved, and a Hg assay was established using flower-shaped nanozymes as recognizers and 3,3',5,5'-tetramethylbenzidine as a signal generator. 2+ Colorimetric sensing method.

The invention provides a method for detecting the total antioxidant capacity of saliva based on iron-based MOF nano-enzyme, and belongs to the field of biosensing. The method comprises the following steps: obtaining an MIL-53Fe nano enzyme; the preparation method comprises the following steps: mixing a diluent of MIL-53Fe nano-enzyme, a sodium acetate buffer solution, 3, 3 ', 5, 5'-tetramethyl benzidine and hydrogen peroxide for reaction, adsorbing a reaction solution by using filter paper, drying and curing by using a chitosan solution to obtain the visual microfluidic detection paper-based chip. Establishing a standard curve of the chromatic value and the ascorbic acid concentration; dropwise adding the treated saliva sample onto the paper-based chip, standing for reaction to obtain a chromatic value, and calculating according to the standard curve to obtain the total antioxidant capacity value of the saliva. Complex matrix interference is broken through, the detection sensitivity and portability are improved, and therefore clinical application of saliva TAC detection in noninvasive health monitoring is promoted.

The invention discloses a nanogold and wood composite material, a preparation method, application and a method for determining the content of glucose in reconstituted tobacco, glucose oxidation is directly catalyzed through the nanogold and wood composite material (AuNPs and wood), the glucose and tetramethyl benzidine (TMB) are subjected to a chromogenic reaction, and the content of the glucose in the reconstituted tobacco is determined by combining the linear relation between absorbance and the glucose concentration. And whether the glucose exists in the reconstituted tobacco and the concentrated solution sample or not and the specific content of the glucose can be accurately judged. The method provided by the invention can quickly obtain a detection result within 30 minutes, is suitable for efficiently screening reconstituted tobacco and concentrated solution samples with the glucose content lower than 0.01 gL <-1 >, can accurately determine the actual content of glucose in the reconstituted tobacco and the concentrated solution, does not need to depend on a standard substance or carry out modeling maintenance, and is simple and convenient to operate. The equipment cost is obviously reduced; and the operation process is simplified.

The application belongs to the technical field of sensors and relates to an array sensor based on cerium-based metal organic framework nanoscale enzyme and detection application of perfluoroalkyl compounds. The array sensor is a Ce-MOF triple enzyme activity array sensor and has multiple independent sensing channels. The sensing channels contain Ce-MOF nanoscale enzyme and chromogenic substrate. The chromogenic substrate includes first, second and third chromogenic substrates. The first chromogenic substrate includes 3,3',5,5'-tetramethylbenzidine. The second chromogenic substrate includes 2,4-diamino phenol and 4-aminoantipyrine. The third chromogenic substrate includes xanthine, xanthine oxidase and nitrogen blue tetrazolium. The MOF nanoscale enzyme array sensor constructed by the application has high sensitivity and selectivity in the identification and differentiation of PFASs compounds. The array sensor can not only accurately distinguish single PFASs compounds but also quantitatively detect the compounds, and has good response to PFASs with different concentrations.

The application discloses a method for colorimetric and photothermal dual-mode detection of aflatoxin B1 in coffee based on MXene@Pt nanozyme, wherein MXene is obtained by etching Ti3AlC2 with LiF and HCl, dopamine carbon dots and sodium borohydride are used as reducing agents, and in-situ reduction technology is adopted to synthesize MXene nanozyme modified with platinum nanoparticles (MXene@Pt). The MXene@Pt shows peroxidase-like activity and photothermal performance enhanced by near-infrared light stimulation, can catalyze the blue deepening of the substrate 3,3',5,5'-tetramethylbenzidine (TMB) and temperature rise, and when aflatoxin B1 exists, the POD-like activity of the MXene@Pt nanozyme is inhibited, and the colorimetric and temperature signals are reduced. The colorimetric and temperature dual-mode sensor detection method for AFB1 is established, and the method has the characteristics of high sensitivity, strong specificity, simple operation, rapidness and the like.

The invention belongs to the technical field of biosensors, and discloses a preparation method and application of a polyacid / hydrotalcite composite mimic enzyme. According to the invention, the P2W18O62 / CoAl-LDH composite material is prepared and is applied to the colorimetric reaction process of 3, 3 ', 5, 5'-tetramethyl benzidine, so that the detection of H2O2 and AA is realized. AA can be used as a reducing agent in the system and can reduce blue oxTMB into colorless TMB. On the basis, a rapid and sensitive TMB / H2O2 / P2W18O62 / CoAl-LDH colorimetric sensing system is established to detect the AA. The linear detection range of AA is 10 to 50 mol / L, and the detection limit is 12.5 mol / L. The sensing system shows excellent selectivity, and the TMB / H2O2 / P2W18O62 / CoAl-LDH sensing system is used for detecting the AA in an actual fruit sample.

The invention provides a multifunctional nano material Ni-MoS2 (at) Au for detecting trace toxic substances in mushrooms and a preparation method of the multifunctional nano material Ni-MoS2 (at) Au. The nano material is prepared from a metal oxide, a surfactant, precious metal nano particles and a solvent, the nano material has colorimetric and Raman detection functions on various trace toxic substances (mercury ions and amanita peptide) in mushrooms, hydrogen peroxide is immediately catalyzed to quickly oxidize 3, 3 ', 5, 5'-tetramethyl benzidine into yellow 3, 3 ', 5, 5'-tetra (tetrafluoromethyl) phenyl diamine oxide after the nano material is in contact with a target object Hg < 2 + > for 1s in a colorimetric mode, the nano material has an extremely low detection limit of 0.036 mu g / mL, and the nano material can be used for detecting various trace toxic substances (mercury ions and amanita peptide) in mushrooms. The catalyst has good selectivity and is not interfered by other heavy metal ions; in a Raman mode, high-sensitivity detection of alpha-amanita peptide and beta-amanita peptide can be realized, and the detection limit ranges are 10 <-4 > M to 10 <-8 > M. The nano material provides a reference mode capable of detecting multiple target objects in the same system, and opens up a new way for a detection strategy of trace toxic substances in the field of food safety detection.

The present application relates to a kind of stable high-efficiency HRP enzymatic green display dye and its preparation method, belong to the field of immunoassay technology, including A liquid and B liquid, A liquid includes ammonium molybdate, polyethyleneimine, alginic acid, sodium pyrophosphate, H2O2 and PB buffer solution;B liquid includes N, N-dimethylformamide, ethylene glycol, N-methyl pyrrolidone, 3, 3', 5, 5'-tetramethyl benzidine hydrochloride hydrate and ethylenediaminetetraacetic acid disodium, when using, A liquid and B liquid are mixed, and green display dye mixed solution is formed.The substrate dye of the present application can form high contrast with brown in double staining, and the sensitivity is high, the staining on quality and membrane positioning is clear and accurate, and also can make long-term, stable preservation of staining result, meet the pathological diagnosis demand of immunohistochemical double staining.

The invention discloses a silk fibroin-based glucose detection platform preparation method, which comprises: mixing cyclodextrin and deionized water to form a homogeneous solution, adding a buffer solution to adjust the pH value range to 4-8, adding 3, 3 ', 5, 5'-tetramethyl benzidine, and uniformly mixing under a dark condition to prepare a 3, 3 ', 5, 5'-tetramethyl benzidine cyclodextrin solution; uniformly mixing a structure regulator with the silk fibroin solution to form a homogeneous precursor solution; uniformly mixing the precursor solution with glucose oxidase, horse radish peroxidase and the 3, 3 ', 5, 5'-tetramethyl benzidine cyclodextrin solution to obtain a base solution; pouring the precursor solution on a microneedle mold, and drying and curing at normal temperature to obtain a microneedle tip; the base solution is poured into a mold containing a needle tip to form a base, demolding is conducted after drying, and the silk fibroin-based glucose detection platform is obtained.

The invention discloses a method for detecting vitamin B1 and glyphosate by a nano-enzyme base, which comprises the following steps of: preparing Cu2O / Mn under ultraviolet irradiation by taking Cu2O as a template and manganese ions as donors, preparing Mn-tetra (4-carboxyphenyl) porphyrin (TCPP) nano-enzyme (Cu2O / Mn at TCPP) with weak pseudoperoxidase activity by a hydrothermal method, and enhancing the affinity between the Cu2O / Mn at TCPP and a substrate 3, 3 ', 5, 5'-tetramethyl benzidine (TMB) by vitamin B1 (VB1), more hydroxyl radicals (. OH) are generated, the activity of pseudoperoxidase is remarkably enhanced, and colorless TMB is oxidized to generate a blue solution; due to the interaction of glyphosate and vitamin B1, the addition of glyphosate can effectively inhibit the affinity interaction of VB1 and TMB, thereby inhibiting the catalytic oxidation reaction; according to the present invention, with the increase of the VB1 concentration, the absorbance of the solution is linearly increased, and with the increase of the glyphosate concentration, the absorbance is linearly reduced, such that the new VB1 and glyphosate detection method is established, the detection limits are respectively 0.20 mg / kg and 0.01 mg / kg, and the detection method has characteristics of strong specificity and no interference of other vitamins and pesticides.

The invention belongs to the technical field of environmental pollutant detection and treatment, and provides a method for detecting and degrading tetracycline by aptamer-modified fluorescent nano-enzyme, which comprises the following steps: firstly, synthesizing an iron-based metal organic framework through hydrothermal synthesis, and coupling with a tetracycline aptamer to construct a nano-enzyme material with endogenous fluorescence and catalytic activity; then, utilizing the aptamer to specifically recognize fluorescence measurable change initiated by tetracycline under a weak acid condition, and establishing a standard curve to realize rapid quantification; tetramethyl benzidine is used as a substrate to verify the peroxidase-like activity of the compound; after detection is completed, hydrogen peroxide is added into the same system, hydroxyl radicals are generated through iron site valence cycle, and tetracycline is subjected to in-situ oxidative degradation. The method is high in sensitivity, strong in interference resistance and simple and convenient in process, the degradation rate within two hours is about 90%, and the method is suitable for on-site'detection-treatment 'integrated application of a water body, aquaculture wastewater and other complex matrixes.

The invention provides a rapid starch content detection kit and application thereof, and belongs to the technical field of food detection.The kit comprises a reaction microwell plate with glucose oxidase and horse radish peroxidase fixed in reaction microwells, amylase working fluid containing alpha-amylase, BSA and amylase diluent, and a reaction microwell plate with glucose oxidase and horse radish peroxidase fixed in reaction microwells, the saccharifying enzyme working solution consists of saccharifying enzyme, BSA (Bovine Serum Albumin) and saccharifying enzyme diluent; and the substrate solution contains tetramethyl benzidine. The starch content detection scheme provided by the invention has the characteristics of simple treatment steps, short time consumption, high specificity, high sensitivity, high accuracy and the like.

The application discloses a hydrogel preparation method based on Hofmeister effect and application in color-changing contact lenses, and comprises the following steps: mixing a blue oxidation state 3,3',5,5'-tetramethyl benzidine solution with an agarose solution, rapidly reacting through microwave, mold pressing and cooling to form a blue contact lens; uniformly coloring the prepared blue contact lens with Hofmeister salt through simple drop or soaking method; and cleaning the colored contact lens. The color-changing contact lens prepared by the preparation method effectively avoids the high production cost and the safety problem of uneven lenses caused by using printing coloring technology, breaks through the fixed limitation that the color of the existing color contact lens cannot be changed once produced, and provides a novel color-changing mechanism and a reliable color-changing method for the current color-changing contact lens market.

The invention discloses a method for visually detecting various phosphates, which comprises the following steps: firstly, synthesizing three MOF (Metal Organic Framework) nano-enzymes, namely PCN-222 (Fe), PCN-223 (Fe) and PCN-224 (Fe) with peroxidase-like activity, catalyzing a colorless substrate 3, 3 ', 5, 5'-tetramethyl benzidine (TMB) into oxTMB in a blue oxidation state by the three MOF nano-enzymes in the presence of H2O2, and generating remarkable colorimetric response; then, the five phosphates, namely ATP (adenosine triphosphate), ADP (adenosine diphosphate), AMP (adenosine monophosphate), PPi (pyrophosphoric acid) and Pi (inorganic phosphate), are simultaneously distinguished and detected by utilizing the principle that different phosphates have different regulation degrees on the peroxidase-like activity of the MOF nano-enzyme. In combination with a smartphone application program 'ColorMax', real-time visual analysis of phosphate is realized, and an efficient and convenient method is provided for distinguishing and detecting different phosphates.

This invention discloses a chromogenic solution and kit for visual colorimetric detection of free ferrous protoporphyrin in cells. The chromogenic solution consists of reagents A, B, and C: Reagent A is prepared with deionized water and contains NaCl, Proclin 300, and glycerol; Reagent B is prepared with an acetate-sodium acetate buffer at pH 4.0 and contains glycerol, Triton X-100, β-cyclodextrin, disodium EDTA, citric acid, ethanol, and 3,3',5,5'-tetramethylbenzidine; Reagent C is prepared with an acetate-sodium acetate buffer at pH 4.0 and contains 2.0-4.0% hydrogen peroxide and 35.0-50.0% ethanol. The chromogenic solution of this invention has a lower background value and can detect the content of free ferrous protoporphyrin in cells within 10 minutes by visual colorimetry, with a detection limit as low as 10 nmol / L. The chromogenic stability is maintained for 12 hours, making it suitable for rapid assessment of cellular pathological conditions.

The application belongs to the technical field of sensors, and provides a biosensor for detecting Escherichia coli, which comprises AuNRs modified with H1 hairpin and H2 hairpin, a hairpin probe HAP, an S-T composite probe, hematin, potassium ions, H2O2 and tetramethyl benzidine; the nucleotide sequences of the hairpin probe HAP, the H1 hairpin and the H2 hairpin are shown in SEQ ID NO:1-3; the S-T composite probe is formed by complementary pairing of an S chain and a T chain with the nucleotide sequences shown in SEQ ID NO:4-5; and the H1 hairpin and the H2 hairpin are electrostatically adsorbed on the surface of the AuNRs. The biosensor provided by the application has high reaction efficiency, good specificity and low detection limit, and is suitable for qualitative and quantitative determination of the number of Escherichia coli.

The invention discloses a biological tissue cell autofluorescence elimination agent and a use method, the autofluorescence elimination agent is composed of an autofluorescence elimination agent component A solution and an autofluorescence elimination agent component B solution, and a solvent is a hydrophilic solvent; the autofluorescence eliminating agent component A is one or a combination of more of phosphomolybdic acid, sodium molybdate, Bingsnow delala green leuco base, 3, 3 ', 5, 5'-tetramethyl benzidine and Sudan black B; the autofluorescence eliminating agent component B is one or a combination of more of stannous chloride, ascorbic acid, sodium pyrosulfite, salvianol B, tris (2-carboxyethyl) phosphine hydrochloride, p-phenylenediamine, polyvinylpyrrolidone K3, sodium polyethylene sulfonate and polyethylene glycol. The method is used for shielding autofluorescence generated by red blood cells, collagen, elastin, aldehyde immobilization and the like, non-specific signal interference is reduced, and the signal-to-noise ratio and sensitivity in fluorescence experimental analysis are improved.

The invention provides a kit for detecting endotoxin and a detection method thereof. The kit comprises: a capture unit: a recombinant crab-like hemocyanin factor C fixed on the surface of a solid phase carrier; the signal probe is composed of a polyclonal anti-lipopolysaccharide antibody coupled with gold nanoparticles and horse radish peroxidase; the reaction buffer solution is a Tris-HCl buffer solution containing calcium ions required by activation of Factor C and a surfactant; the signal substrate solution is a peroxidase chromogenic substrate solution containing 3, 3 ', 5, 5'-tetramethyl benzidine; the stop solution comprises a dilute sulphuric acid solution and an endotoxin standard substance. The rapid, high-sensitivity and high-specificity endotoxin detection kit based on the recombinant factor C and the nano signal amplification technology has the advantages of high specificity, interference resistance, high sensitivity, rapidness, convenience and the like, and is wide in application prospect.

The application relates to the field of biological monitoring and particularly belongs to a detection method of chlorogenic acid and application thereof. The method comprises the following steps: taking palladium nitrate, iron nitrate nonahydrate and glutathione as raw materials to prepare FePd2S4 nano-enzyme particles; mixing different concentrations of chlorogenic acid standard solution with acetic acid-sodium acetate buffer solution, H2O2, 3,3',5,5'-tetramethylbenzidine and FePd2S4 nano-enzyme suspension, incubating, measuring the absorbance value at 652 nm, taking the concentration of chlorogenic acid as the abscissa and the absorbance difference as the ordinate, drawing a standard curve and obtaining a linear equation; processing a sample to be measured, extracting chlorogenic acid in the sample to be measured, and preparing a sample solution; taking the sample solution to replace the chlorogenic acid standard solution to repeat the above steps and measure the absorbance value; and calculating the content of chlorogenic acid in the sample to be measured according to the linear equation of S.2. The method has the advantages of simplicity, low cost, high stability, environmental friendliness and the like and is suitable for large-scale preparation.

The invention discloses a sensing material for distinguishing thiophene sulfides and a distinguishing detection method, and the sensing material is prepared from the following components in parts by weight: each 1.5 mL of the sensing material contains 0.0018 to 0.002 mg of a PtFe nano material, 0.10 to 0.15 mg of 3, 3 ', 5, 5'-tetramethyl benzidine and 0.50 to 0.55 mg of H2O2. The method for distinguishing and detecting the thiophene sulfides comprises the following steps: (1) mixing a PtFe nano material with 3, 3 ', 5, 5'-tetramethyl benzidine and H2O2 in more than two pH environments, adding different types of thiophene sulfides to obtain different absorbance values under 652nm, and generating an LDA distinguishing map and a clustering heat map on the basis of obtained characteristic absorbance data; and (2) carrying out parallel experiments on thiophene sulfides to be distinguished according to the experimental parameter flow in the step (1), matching data of a sample to be detected with reference data, and distinguishing and identifying the thiophene sulfides to be detected by combining LDA analysis and a clustering heat map visualization result. According to the invention, thiophene sulfide can be distinguished, and identification application in air pollutants is manifested.

The present application relates to the field of analytical chemistry and food and pharmaceutical testing technology, and particularly relates to a rutin antioxidant activity colorimetric determination method based on composite nano-enzyme, comprising: mixing a to-be-detected sample solution and an ABTS free radical cation working solution to perform a first reaction, so that antioxidant substances in the sample and ABTS free radical cations perform a scavenging reaction; adding the composite nano-enzyme, 3,3',5,5'-tetramethylbenzidine solution and hydrogen peroxide solution to the system after the first reaction is completed, to initiate a second reaction; measuring the absorbance value of the system at a specific wavelength after the second reaction, and comparing the absorbance value with a standard curve obtained through the same steps, to calculate the antioxidant activity in the to-be-detected sample in terms of the equivalent concentration of rutin; through optimization of the reaction conditions, the method of the present application simplifies the operation steps, and can provide accurate measurement results in a wider concentration range.

The application belongs to the technical field of colorimetric detection, and particularly relates to application of a high-entropy sulfide nano-enzyme material in colorimetric analysis and detection of sulfadiazine. The application uses metal nitrates of Fe, Co, Cu, Cr and Zr and TAA as raw materials to synthesize a five-element high-entropy sulfide nano-enzyme material (F3CZ-48). The F3CZ-48 is used as a colorimetric analysis and detection method with peroxidase activity based on tetramethyl benzidine (TMB) as a chromogenic substrate, and a new method for detecting sulfadiazine (SD) is established. The F3CZ-48 has high stability, easy storage, low cost, excellent catalytic performance and rich reaction sites. By fitting the change of UV-Vis intensity with the concentration of SD, a linear calibration curve with a correlation coefficient of 0.993 is obtained, and the detection limit is 0.121 muM (S / N=3). The material has good sensitivity, selectivity and reproducibility for colorimetric detection of SD, and provides a new scheme for designing a new catalyst for detecting SD.

The present invention aims to prevent deliquescence of an ozone remover in an ozone adsorbent in an ozone scrubber, an ozone removal method, an aldehyde trapping device, and an aldehyde trapping method, thereby suppressing clogging of the ozone scrubber and the appearance of ghost peaks in the aldehyde measurement results. [Solution] The ozone adsorbent (8) of the ozone scrubber (2) is an ozone removing agent that does not deliquesce even at high temperatures and high humidity, by carrying 3,3',5,5'-tetramethylbenzidine on a diatomaceous earth carrier. The ozone scrubber (2) is connected to an aldehyde collector (3), and the aldehyde collector (3) is connected to a suction pump (6). By operating the suction pump (6), ozone is adsorbed in the ozone scrubber (2) and aldehyde is adsorbed in the aldehyde collector (3).

The invention discloses a construction method and application of a smartphone-assisted organophosphorus pesticide detection sensor, and belongs to the technical field of analysis and detection. The method comprises the following steps: firstly, synthesizing UIO-66 (at) MnO2 nano-enzyme which has relatively high oxide-like enzyme activity so as to catalytically oxidize 3, 3 ', 5, 5'-tetramethyl benzidine (TMB) to develop color; acetylcholin esterase is utilized to catalyze hydrolysis of acetylthiocholine to generate reducing substances, the chromogenic reaction of TMB is inhibited, and the organophosphorus pesticide can specifically inhibit the activity of acetylcholin esterase, so that the chromogenic reaction is recovered; the reaction solution is shot through Color Grab software of the smart phone, an RGB value is output, a gray value is calculated, a linear relation between the gray value and the pesticide concentration is established, and quantitative detection of the organophosphorus pesticide is achieved. The sensor constructed by the invention is high in sensitivity, good in selectivity, simple and convenient to operate and low in cost, can be successfully applied to rapid detection of organophosphorus pesticides in food and environmental samples, and has a good practical application prospect.