144 results about "Methyl blue" patented technology

The invention relates to the technical field of dye separation, and discloses a loose nanofiltration membrane and a preparation method and application thereof.The loose nanofiltration membrane is prepared from a multi-acyl chloride organic solution and an amine monomer water-phase solution on the surface of a porous supporting membrane through a one-step interfacial polymerization method, and the rejection rate of the loose nanofiltration membrane to methyl blue, Congo red and other dyes is 95% or above; meanwhile, the loose nanofiltration membrane has high water permeability and excellent dye / inorganic salt separation selectivity, and is expected to have wide application prospects in the fields of dye production and purification and dye wastewater desalination.

The invention discloses a construction method and application of a zwitter-ion antifouling and dual-signal-ratio electrochemical biosensor, and belongs to the technical field of biochemical sensing analysis and life science. According to the invention, 3-aminopropyl dimethylamine oxide (APDMAO) zwitterions are prepared to be used as an antifouling interface. Specific positive and negative charges (N < + >-O-) of APDMAO promote hydrogen bond combination with water molecules, and a firm hydration barrier is formed. Meanwhile, the development of APDMAO overcomes the defect that zwitterions are difficult to synthesize and modify, and the application of APDMAO in biosensing analysis is expanded. A methylene blue (MB) internal standard modified alpha fetoprotein (AFP) aptamer is coupled with APDMAO under a controllable potential, so that the detection precision of the sensor is improved. The constructed ratio type electrochemical antifouling biosensor realizes sensitive and accurate detection of AFP, and the detection limit is as low as 3.41 fg / mL.

The invention provides a carbonized polymer dot with high-temperature-resistant surface activity and solid-state luminescence as well as a preparation method and application of the carbonized polymer dot. The preparation method of the carbonized polymer point with high-temperature-resistant surface activity and solid luminescence comprises the following steps: uniformly mixing a precursor, a polyether long-chain polymer, acid and water, carrying out hydrothermal reaction, and then purifying and freeze-drying to obtain the carbonized polymer point with high-temperature-resistant surface activity and solid luminescence, the precursor is rhodamine B, methyl blue, fluorescein sodium or calcein. The preparation method disclosed by the invention is simple, environment-friendly, cheap and easily available in raw materials, low in cost and high in yield; reaction conditions are easy to realize; the carbonized polymer dot prepared by the invention has both high-temperature-resistant surface activity and solid-state luminescence property, can emit high-brightness red light, has higher solid quantum yield and good biocompatibility, has the capability of serving as commercial fluorescent powder and a surfactant, and has extremely high practical application value in the fields of solid-state illumination, petroleum industry and the like.

The invention discloses a high-entropy spinel ferrite catalyst for efficiently degrading dyes and antibiotics as well as a preparation method and application of the high-entropy spinel ferrite catalyst. The Cu1 / 2Zn1 / 2Fe2 / 3Co2 / 3Ni2 / 3O4 (HEO-FNCCZ) high-entropy spinel ferrite catalyst is prepared by adopting a sol combustion method, the photocatalytic degradation performance of common dyes and antibiotics is evaluated by simulating visible light photocatalysis, and the reaction mechanism of photocatalytic degradation of methylene blue with the best effect is researched. The photocatalytic reaction is effectively promoted by utilizing the catalytic effect of the spinel ferrite, so that environment-friendly pollutant degradation is realized. According to the method, the production process is simple, various organic toxic and harmful substances are not introduced, the method is nontoxic and harmless in the use process, the recovery efficiency of the catalyst exceeds 95%, and the method has the characteristics of remarkable degradation effect and no secondary pollution; the preparation method only relates to the processes of dissolving, calcining, crushing and the like, and is extremely suitable for industrial batch production.

The invention belongs to the technical field of piezoelectric catalytic materials, and particularly relates to a piezoelectric catalytic material based on a wood porous structure and a preparation method of the piezoelectric catalytic material. The invention provides a piezoelectric catalytic material based on a wood porous structure. The piezoelectric catalytic material comprises wood with a porous structure, molybdenum disulfide and reduced graphene oxide, wherein the molybdenum disulfide and the reduced graphene oxide are loaded on the porous structure. Molybdenum disulfide, reduced graphene oxide, rGO and MoS2 are loaded on the porous wood to form a nano heterojunction, so that the porous wood has the characteristics of good conductivity and high carrier separation efficiency, carriers (electrons and holes) generated by MoS2 in the piezoelectric process can be effectively captured and transmitted, the piezoelectric catalytic performance of the porous wood is improved, and the preparation method is simple and easy to implement. Under normal-temperature and ultrasonic conditions, the composite material has relatively high degradation efficiency on organic dyes (methylene blue and rhodamine B), and has relatively high cyclic utilization rate.

The invention belongs to the technical field of printing and dyeing wastewater treatment, and particularly relates to a g-C3N4-based adsorbent and a synthesis method thereof.The method comprises the steps that urea is put into a drying oven to be dried, dried urea is obtained, lauryl sodium sulfate is added into the dried urea, mixing and grinding are conducted, a mixture is obtained, then the mixture is transferred into a crucible to be calcined, and a calcined product is obtained; and cooling the calcined product to room temperature, washing and drying to obtain the g-C3N4-based adsorbent. According to the preparation method, the lauryl sodium sulfate is added firstly and then calcined, so that the electronegativity of the product is effectively improved, the electrostatic adsorption capacity to cationic methylene blue is remarkably improved, and the adsorption rate is finally improved.

The invention relates to a method for preparing a magnetic Fe3O4 / Cu / nitrogen-doped carbon composite material by a one-step method and an application of the magnetic Fe3O4 / Cu / nitrogen-doped carbon composite material, and aims to solve the problems of poor catalytic activity, complex separation and recovery and complex synthesis method of the existing PMS activated catalytic material. According to the method, melamine is selected as a carbon source and a nitrogen source, ferric nitrate and copper sulfate are selected as an iron source and a copper source respectively, and the magnetic Fe3O4 / Cu / nitrogen-doped carbon composite material is synthesized in one step by adopting a high-temperature pyrolysis method. The adsorbent not only has excellent adsorption performance on dye-methylene blue, but also can realize high-efficiency oxidative degradation. The magnetic Fe3O4 / Cu / nitrogen-doped carbon composite material prepared by the invention not only has excellent catalytic performance, but also is easy to magnetically separate and recycle, and is suitable for efficient treatment of dye wastewater. The method is applied to the field of catalytic degradation of wastewater.

The invention relates to the field of cationic dye sewage treatment. The preparation method comprises the following steps: respectively dissolving sodium alginate (SA), octadecyl trimethyl ammonium chloride (STAC) and poly (sodium p-styrenesulfonate) (PSSS) in deionized water to prepare solutions, then mixing the three solutions together, uniformly stirring to form a mixed solution, dropwise adding the mixed solution into a CaCl2 solution, cross-linking and curing to form microspheres, and drying the microspheres to obtain the gel microspheres (SA-PSSS-H). Taking out the microspheres, repeatedly washing the microspheres with deionized water, placing the microspheres in a hydrochloric acid solution for H < + > replacement, repeatedly washing the replaced microspheres with deionized water, and drying to constant weight to obtain the efficient methylene blue dye adsorption gel microspheres (SA (at) PSSS-H). The prepared gel microspheres capable of efficiently adsorbing the methylene blue dye have high adsorption capacity on cationic dye and can efficiently adsorb the cationic dye.

The invention provides a dual-mode portable biosensor for detecting pseudomonas aeruginosa and application of the dual-mode portable biosensor, and belongs to the technical field of biosensors. The dual-mode portable biosensor comprises a closed bipolar electrode, magnetic beads for detecting pseudomonas aeruginosa, a methylene blue solution, a TCEP solution, a Ru (bpy) 3 < 2 + > solution, boron nitride quantum dots and a TPrA solution. The portable biosensor can rapidly and accurately detect the content of pseudomonas aeruginosa in a sample under low driving voltage, is high in sensitivity, good in specificity, high in anti-interference performance, good in repeatability and convenient to carry, and can be used for field detection. Pseudomonas aeruginosa adsorbed on the detected electrode is effectively killed by adopting copper ions, so that collaborative development of dual functions of detection and sterilization is realized, and environmental pollution is effectively avoided.

The application discloses a high-efficiency degradation of dyes and antibiotics high-entropy spinel ferrite catalyst and a preparation method and application thereof. 1 / 2 Zn 1 / 2 Fe 2 / 3Co 2 / 3 Ni 2 / 3 O4(HEO-FNCCZ) high-entropy spinel ferrite catalyst, the photocatalytic degradation performance of common dyes and antibiotics is evaluated by using simulated visible light photocatalysis, and the reaction mechanism of the photocatalytic degradation of methylene blue with the best effect is studied. The catalytic effect of the spinel ferrite is utilized to effectively promote the photocatalytic reaction, so that the environment-friendly pollutant degradation is realized. The method has the characteristics of simple production process, no introduction of various organic toxic and harmful substances, non-toxic and harmless in use, catalyst recovery efficiency more than 95%, and no secondary pollution. The preparation method only involves processes such as dissolving, calcining and crushing, and is extremely suitable for industrialized batch production.

The invention discloses a black phosphorus-methylene blue nano composition for improving blood brain permeability and a synthesis method thereof. The synthesis method comprises the following steps: step 1, mixing black phosphorus nanosheets with polyethylene glycol for reaction; step 2, carrying out centrifugal cleaning on the reaction liquid in the step 1, and collecting a lower-layer reactant; step 3, adding aminated superparamagnetic nanoparticles and methylene blue into the lower reactant obtained in the step 2 for reaction; and 4, carrying out centrifugal cleaning on the reaction liquid obtained in the step 3, and collecting a lower-layer reactant. The invention also discloses the black phosphorus-methylene blue nano composition synthesized by the synthesis method, the drug loading rate of methylene blue in the composition exceeds 60%, and the composition has good biological safety, is non-toxic to cells and mice, is very simple and convenient in preparation process, and has a wide application prospect in the aspect of improving the blood-brain barrier permeability.

The invention belongs to the technical field of preparation and application of metal organic framework adsorption materials, and particularly relates to a Ti-MOF-based nanometer material, a preparation method thereof and application of the Ti-MOF-based nanometer material in methylene blue dye adsorption, and a hierarchical pore Ti-MOF-based nanometer methylene blue adsorbent rich in oxygen vacancies is constructed by means of a temperature regulation and control ligand pyrolysis strategy. Adsorption performance tests show that the adsorbent has high adsorption capacity and high adsorption rate on methylene blue, due to the fact that hierarchical pores in the adsorbent promote diffusion and mass transfer of methylene blue, and oxygen vacancies enhance electronegativity of the surface of the adsorbent and provide more adsorption active sites.

A flexible near-infrared II region photodetector based on two-dimensional material nanoribbons relates to the technical field of optoelectronic devices, and solves the problems of poor flexibility and low responsivity of existing near-infrared II region photodetectors. It includes: a flexible substrate; an inorganic nanoribbon array disposed on the upper surface of the flexible substrate; a metal electrode disposed on the upper surface of the inorganic nanoribbon array; an organic modification layer connecting the inorganic nanoribbon array, and the near-infrared II region spectral absorption rate of the organic modification layer is not lower than that of methylene blue, porphyrin compounds or indocyanine green in the near-infrared II region. The preparation method is: preparing an inorganic nanoribbon array on the flexible substrate; preparing an organic modification layer on the inorganic nanoribbon array. The present invention improves the optoelectronic conversion efficiency of the device through the energy band distribution and coupling between two-dimensional organic and inorganic materials; improves the responsivity of the device in the near-infrared II region; can be attached to the surface of a living body for real-time detection of a moving living body.

This invention discloses a molecularly switched adsorbent for adsorbing triphenylmethane dyes and its application, belonging to the field of wastewater treatment technology. The molecularly switched adsorbent proposed in this invention can rapidly remove triphenylmethane dyes such as crystal violet, malachite green, and methylene blue dyes from water; it can remove tens of ppm concentrations of crystal violet, malachite green, and methylene blue dyes from water in a very short time (90 min), with a removal rate of ≥92%. Moreover, this adsorbent can maintain a removal rate of ≥90% under a wide pH range (6-11) and high ion concentration conditions (1M). The activation and regeneration conditions of the adsorbent of this invention are mild; dye molecules can be removed by elution in a low-concentration alkaline solution only a few times. The adsorbent can be continuously recycled at least 10 times without significant attenuation of adsorption capacity.

The invention provides biomass carbon as well as a preparation method and application thereof in piezoelectric electro-catalytic degradation of methylene blue. The invention also provides a method. Coffee grounds are used as a biomass charcoal precursor, efficient recycling of organic waste is achieved, the raw material cost is reduced, and the method conforms to the circular economy concept. The ZnO coating with controllable atomic-scale thickness and uniform distribution is realized, and the agglomeration problem of a traditional method (such as an impregnation method) is solved. ALD can be carried out at low temperature, so that the pore structure of the biomass charcoal is prevented from being damaged by high temperature, and the activity of zinc oxide is kept. Through ALD precursor selection (such as diethyl zinc and water vapor) and cycle index optimization, chemical bonding of ZnO and biomass charcoal is enhanced, and the stability of the composite material is improved. The natural porosity (micropore-mesopore) of the coffee residue biomass charcoal is combined with ZnO nanoparticles deposited by ALD, so that a high specific surface area and active sites are provided.

The present invention belongs to the technical field of biosensors, and particularly relates to a method for simultaneous ratio electrochemical detection of Pb<supgt;2+< / supgt> and Hg<supgt;2+< / supgt> based on electric field-regulated aptamer orientation at the sensing interface. The present invention designs complementary cDNA labeled with anthraquinone (AQ), and simultaneously combines Pb<supgt;2+< / supgt> aptamer labeled with methylene blue (MB) and Hg<supgt;2+< / supgt> aptamer labeled with ferrocene (Fc), and constructs a sensing interface with a DNA structure synthesized by PCR. During the pre-enrichment process, the electric field first pushes the ions close to the aptamer and keeps them away from the DNA, which is beneficial for subsequent recognition; then, when testing the electrochemical signal, the DNA with the retained direction of the electric field provides a stable current for AQ as the detection reference signal. Thus, a novel dual-ratio electrochemical aptamer sensor is constructed to achieve specific enrichment and accurate detection of Pb<supgt;2+< / supgt> and Hg<supgt;2+< / supgt>; the present invention provides a new method for manufacturing high-performance electrochemical sensors for heavy metal ion detection.

The present invention belongs to the field of biomedicine technology and discloses a nanomotor drug-loaded particle and its preparation method and application. The nanomotor drug-loaded particle is formed by loading platinum nanoparticles and methylene blue drugs on a DNA tetrahedron structure. The nanomotor drug-loaded particle can enhance the uptake of the photosensitizer methylene blue (MB) by tumor cells while achieving deep penetration into tumors, thereby reducing the amount of drugs required for conventional systemic cancer treatment. The nanomotor drug-loaded particles are safer and have fewer adverse reactions. The nanomotor drug-loaded particles provided by the present invention have a reliable source, are simple to prepare, have high biocompatibility, specifically respond to photodynamic therapy, and effectively inhibit tumor cell growth.

This invention belongs to the field of SERS detection technology, specifically relating to an Ag-Cu 0.5 Zn 0.5 Application of Fe2O4 composite SERS substrate in the detection of methylene blue in wastewater. First, Cu was prepared using a calcination method. 0.5 Zn 0.5 Fe2O4 nanomaterials, and then Ag NPs are grown on Cu 0.5 Zn 0.5 Ag-Cu was prepared on Fe2O4 support surface. 0.5 Zn 0.5 Fe2O4 composite SERS substrate was loaded onto a glass slide. This substrate integrates the LSPR effect of Ag NPs and Cu. 0.5 Zn 0.5 The cation rearrangement and lattice distortion effects introduced by Fe2O4 optimize the separation and migration behavior of photogenerated charges. The abundant defect states and tunable electronic structure brought about by Cu / Zn synergistic regulation are conducive to constructing efficient interfacial charge transfer channels, thereby enhancing the Raman signal and enabling the detection of trace amounts of methylene blue in wastewater.

The invention discloses a quercetin composite methyl blue light catalyst and a preparation method and application thereof, and relates to the technical field of photocatalyst preparation, and the preparation method comprises the following steps: S1, placing quercetin and methyl blue in a beaker, adding deionized water, then adding H2SO4 and absolute ethyl alcohol, and stirring to obtain a mixed solution; s2, transferring the mixed solution into a hydrothermal reaction kettle with a polytetrafluoroethylene lining for constant-temperature reaction; and S3, after the constant-temperature reaction is finished, cooling to room temperature, washing a reaction product with deionized water, and then drying and grinding the reaction product into powder. According to the photocatalyst disclosed by the invention, a stable compound structure is constructed by utilizing the dihydrogen-bond interaction between hydroxyl of quercetin and sulfo and amino of methyl blue, and the photocatalytic activity is remarkably enhanced. Under the irradiation of visible light, the prepared photocatalyst shows excellent lignite depolymerization performance, and humic acid and fulvic acid rich in hydroxyl and amino can be efficiently generated.

The present invention relates to a method for improving the detection performance of an electrochemical biosensor and its application in a ratiometric electrochemical biosensor. Methylene blue and cholesterol-modified double-stranded DNA probes are immobilized on a gold electrode modified with a 1-hexanethiol assembly layer via hydrophobic interaction, thereby improving the stability of the methylene blue at the gold electrode interface and the immobilization efficiency of the double-stranded DNA probe at the gold electrode interface. In a potassium ferricyanide-mediated electrocatalytic system, the methylene blue on the gold electrode serves as a signal unit, and ferrocene is introduced as another signal unit. The 1-hexanethiol assembly layer on the gold electrode can shield [Fe(CN)6] 3‒ Electron transfer between the electrode interface and methylene blue enables simultaneous signal amplification of both methylene blue and ferrocene. Methylene blue, acting as an electron mediator, enhances the signal response of ferrocene, achieving secondary signal amplification of ferrocene, thereby improving sensor detection sensitivity. The ratiometric electrochemical biosensor constructed using this method exhibits excellent sensitivity, accuracy, and selectivity.

The invention provides a living cell surface double-tumor marker in-situ detection method based on a closed bipolar electrode (cBPE) array and an electrochemiluminescence (ECL) technology. The living cell surface double-tumor marker in-situ detection method is used for synchronously quantifying carcino-embryonic antigen (CEA) and alpha-fetoprotein (AFP). According to the system, the high specific surface area, the ordered porous structure and the rich surface amino active sites of a covalent organic framework (COF) material are utilized, and the excellent conductivity and biocompatibility of gold nanoparticles (Au NPs) are combined, so that the bifunctional signal probe COF (at) Au (at) MBApt is constructed. The probe can simultaneously load a large number of signal molecule methylene blue (MB) and is coupled with a targeting aptamer (Apt), so that high-capacity labeling and specific recognition of a target marker are realized.

The invention discloses a preparation method of a CdIn2S4 and InVO4 composite material for promoting photocatalytic degradation of an organic dye methylene blue, InVO4 is synthesized through a hydrothermal reaction, then spherical InVO4 is modified on the surface of spherical CdIn2S4, and a unique peanut-shaped CIS-2IVO composite material is successfully constructed, so that the light absorption capacity of CIS-2IVO is enhanced, the conversion from light energy to chemical energy is promoted, and the photocatalytic degradation of the organic dye methylene blue is promoted. The separation and migration efficiency of photon-generated carriers is remarkably improved, the compound loss of electron-hole pairs is reduced, the chemical stability of the composite material is enhanced, and the loss of active components in the reaction process is effectively inhibited, so that the service life of the catalyst is prolonged while the degradation efficiency is greatly improved, and the cost is reduced. And a practical and innovative solution is provided for efficient photocatalytic degradation of organic pollutants. The method is easy and convenient to operate and high in controllability, and the light response range is effectively widened.

This invention discloses a method for measuring methylene blue based on the inner filter effect of chlorophyll carbon quantum dots (CQDs). This method uses CQDs as fluorescent probes and exploits the inner filter effect of CQD fluorescence quenching to detect the CQD content. The method is simple and convenient to operate, highly sensitive, and can rapidly complete sample determination. The CQDs are produced from biomass, resulting in low cost and broad application prospects.

The application relates to the technical field of full-color photopolymer, and specifically discloses a full-color photopolymer film, a preparation method and application thereof. The full-color photopolymer film provided by the application specifically comprises 40-50 parts of writing monomers, 0.8-1.2 parts of photosensitizers, 4-7.2 parts of photoinitiators, 14-16 parts of polycaprolactone glycol, 21-25 parts of aliphatic polyether isocyanate, 4-6 parts of crosslinking agents, 0.3-0.6 parts of defoaming agents, 0.8-1.2 parts of anti-oxidation inhibitors, 0.8-1.2 parts of catalysts and 5-8 parts of solvents; the photosensitizer is composed of 2,5-bis((2,3,6,7-tetrahydro-1H,5H-pyrido[3,2,1-ij]quinolin-9-yl)methylene)cyclopentan-1-one and methylene blue. By using the technical scheme, the full-color photopolymer with high red, blue and green light diffraction efficiency and high refractive index modulation degree can be obtained.

The invention provides a molecular classifier for detecting gastric cancer miRNA. A preparation method of the molecular classifier comprises the following steps: depositing a PABA modification layer on the surface of a screen-printed electrode; activating carboxyl on the surface of the para aminobenzoic acid modification layer by adopting an EDC / NHS composite system; carrying out amination modification on an MXene material, and coating the surface of the activated para aminobenzoic acid modification layer with the modified MXene material to form an MXene functional layer; depositing gold nanoparticles on the surface of the MXene functional layer to obtain an electrochemical activity sensing interface; a signal reporter molecule is combined with an aptamer probe, the signal reporter molecule is a DNA tetrahedron-methylene blue complex, and the combined complex is dropwise added on the surface of an electrochemical activity sensing interface, so that the aptamer probe is combined on the surface of the electrochemical activity sensing interface. The molecular classifier can be used for preparing gastric cancer miRNA detection products, and the problems that in the prior art, a classifier is high in complexity and high in signal leakage risk are solved.

The present application relates to a kind of functional materials for organic dye adsorption and degradation and its preparation method and application, belong to pollutant degradation field.The present application uses one-step hydrothermal synthesis method, with anhydrous ferric chloride, tin chloride tetrahydrate and sodium hydroxide as raw material, successfully constructs the Fe (Sn (OH) 6) / FeSnO (OH) 5 heterojunction composite material with close interface combination.The material can realize the efficient removal of typical organic pollutants methylene blue at normal temperature and pressure, and the degradation rate can reach more than 90% in a short time, showing excellent adsorption and degradation performance.The present application has simple process, mild reaction condition, low raw material cost, avoids complex post-processing process, has good scalability and application potential.The material can provide an efficient, economical technical solution for the treatment of refractory organic pollutants in water, has significant environmental benefits and practical application value.

The invention discloses a preparation method of a cerium dioxide coated gold-palladium bimetallic nano cuboid composite material, and belongs to the field of composite materials. The preparation method comprises the following steps: taking a noble metal gold-palladium bimetallic nano cuboid structure as a core; and the shell layer is a cerium dioxide coating layer. The method comprises the following specific steps: firstly, synthesizing a gold nanorod structure; then synthesizing a gold-palladium bimetallic nano cuboid structure; then, synthesizing a cerium dioxide coated gold-palladium bimetallic nano cuboid composite structure; and finally, carrying out photocatalysis test by using the gold-palladium bimetallic nano cuboid / cerium dioxide composite nano structure. The prepared composite nanostructure combines the advantages of high absorptivity of precious metal in a visible light wave band and even a near-infrared wave band and high photocatalytic efficiency of semiconductor cerium dioxide. Under the irradiation of simulated sunlight, the composite nano photocatalyst can effectively degrade the organic pollutant methylene blue, which shows that the composite nano photocatalyst has excellent photocatalytic activity and wide application prospect.

This invention discloses a quercetin-methylene blue composite photocatalyst, its preparation method, and its application, relating to the field of photocatalyst preparation technology. The method includes the following steps: S1: Quercetin and methylene blue are placed in a beaker, deionized water is added, followed by H2SO4 and anhydrous ethanol, and the mixture is stirred to obtain a mixed solution; S2: The mixed solution is transferred to a hydrothermal reactor with a polytetrafluoroethylene liner for a isothermal reaction; S3: After the isothermal reaction, the mixture is cooled to room temperature, the reaction product is washed with deionized water, and then dried and ground into powder to obtain the final product. The photocatalyst of this invention utilizes the double hydrogen bond between the hydroxyl groups of quercetin and the sulfonic acid and amino groups of methylene blue to construct a stable composite structure, significantly enhancing its photocatalytic activity. Under visible light irradiation, the prepared photocatalyst exhibits excellent depolymerization performance in lignite, efficiently generating humic acid and fulvic acid rich in hydroxyl and amino groups.

The present application provides method for producing methylene blue that includes the steps of providing a reaction mixture having one or more methylene blue intermediates; precipitating metal from the reaction mixture; and producing therefrom crude methylene blue. The crude may further be purified, resulting in methylene compounds having low impurities, preferably having a purity greater than about 97%, having Azure B impurity no greater than 2.5%, and / or a total metal content no greater than 77 ppm. Formulations containing such compounds are also provided.

The present invention relates to a method for analyzing the adsorption mechanism of amino-functionalized magnetic graphene oxide on methylene blue in wastewater, belonging to the technical field of wastewater treatment. In the present invention, kinetic adsorption experiments and isothermal adsorption experiments of amino-functionalized magnetic graphene oxide on methylene blue are respectively carried out in water bodies, and the adsorption kinetic model and isotherm model are respectively analyzed; the equilibrium thermodynamic parameters in the process of amino-functionalized magnetic graphene oxide adsorbing methylene blue are calculated, and the heat transfer mode of the adsorption reaction of amino-functionalized magnetic graphene oxide on methylene blue is determined according to the equilibrium thermodynamic parameters; FTIR spectral analysis is carried out on amino-functionalized magnetic graphene oxide before and after adsorbing methylene blue, and the adsorption mechanism of amino-functionalized magnetic graphene oxide on methylene blue in wastewater is determined in combination with the kinetic model. During the adsorption process of methylene blue, there are electrostatic interaction, hydrogen bond interaction and π-π conjugate interaction between amino-functionalized magnetic graphene oxide and methylene blue.