49 results about "Chloroauric acid" patented technology

This invention discloses gold nanoparticle-modified metal oxide framework materials, their preparation methods, and applications, relating to the fields of material preparation and detection technology. The preparation method of the gold nanoparticle-modified metal oxide framework material includes: in-situ reduction of chloroauric acid on the surface of ZIF-67 via a reduction method to obtain an Au / ZIF-67 composite material; and calcination of the Au / ZIF-67 composite material using a programmed temperature rise process to obtain the final product. This invention also provides applications of this material in serum metabolite detection and in screening metabolic biomarkers for esophageal cancer diagnosis. The composite material prepared by this invention possesses a unique hollow porous structure and uniformly distributed gold nanoparticles, providing a large specific surface area for enriching metabolites in serum. It also enhances the ultraviolet absorption and photothermal conversion efficiency of the nanocomposite material, while improving the material's conductivity, thereby significantly improving laser desorption / ionization efficiency and achieving high-sensitivity detection.

This invention belongs to the field of biosensing technology, specifically relating to a modified carbon fiber electrode for detecting dopamine, its preparation method, and its application. The modified carbon fiber electrode comprises a carbon fiber electrode onto which gold-platinum bimetallic nanoparticles and polydopamine are sequentially modified. The preparation method specifically includes: firstly, modifying the surface of activated carbon fiber filaments with chloroauric acid and sodium citrate to obtain Au@CF; then, modifying the Au@CF surface with ascorbic acid and chloroplatinic acid to obtain platinum nanoparticles, obtaining Au / Pt@CF; finally, immersing the Au / Pt@CF in a dopamine solution to coat the Au / Pt@CF surface with polydopamine, obtaining PDA@Au / Pt@CF. This electrode has advantages such as high sensitivity, low detection limit, strong anti-interference ability, good biocompatibility, and high mechanical stability, making it suitable for dynamic monitoring of dopamine in the living brain.

This invention relates to a near-infrared low-potential electrochemiluminescence dual-ligand stabilized gold nanoclusters, their preparation method, and applications. The method uses chloroauric acid as the gold source and thiomalic acid and sodium citrate as reducing and stabilizing agents, respectively, in a two-step synthesis. First, Au is reduced online using thiomalic acid. 3+ Water-soluble gold nanoclusters were prepared using a novel method. These nanoclusters were then incubated with sodium citrate, and based on the ligand exchange principle, gold nanoclusters co-coated with thiomalic acid and sodium citrate were synthesized. The raw materials required for this invention are readily available and all possess good water solubility. The synthesis apparatus is simple, the conditions are mild, and the operation is safe. The resulting dual-ligand-coated gold nanoclusters exhibit good stability and produce low-potential near-infrared electrochemiluminescence in the long-wavelength region in an aqueous system. This overcomes the limitation of most current electrochemiluminescent materials requiring hydrazine hydrate or carbazide as a co-reactant. Using a non-toxic tert-butylamine-borane co-reactant, low-potential electrochemiluminescence radiation of 0.57V in the near-infrared region was generated.

The application discloses a kind of synergistic antitumor porphyrin-based covalent organic framework heterojunction materials and preparation method thereof, belong to biological medicine technical field. 5,10,15,20-tetra (4-aminobenzene) -21H,23H-porphyrin and 2,5-divinyl benzene formaldehyde are added to organic solvent to carry out solvothermal reaction, and porphyrin-based covalent organic framework (pCOF) is obtained;pCOF is mixed with 1,2-ethanedithiol and heated to obtain thiolated modified pCOF;Thiolated modified pCOF is stirred with glutathione aqueous solution ultrasonically, then tetra-chloroauric acid is added to carry out reaction, and synergistic antitumor porphyrin-based covalent organic framework confined gold nanocluster heterojunction material, recorded as Au@pCOF, is obtained.The Au@pCOF prepared in the application can be used as a kind of biocompatible antitumor therapeutic agent, under the irradiation of 808 nm near-infrared light, active oxygen is efficiently generated and heat is released, photothermal and photodynamic synergistic enhancement is realized, tumor cells are significantly killed, and is used for space-time integration synergistic antitumor therapy.

The application discloses a kind of CL-AuNPs@CD-MOF / Zein-PLA antibacterial films and preparation method and application thereof.The application is prepared gold nanoparticle (AuNPs) by green synthesis strategy, with CD-MOF as stabilizer, p-coumaric acid (p-CA) as natural reducing agent, by reducing tetrachloroauric acid (HAuCl4), CD-MOF is obtained by covalent crosslinking modification CL-AuNPs@CD-MOF with diphenyl carbonate (DPC), finally it is introduced into corn alcohol-soluble protein (Zein)-polylactic acid (PLA) composite film, utilize Zein excellent oxygen barrier property and PLA excellent mechanical property mutual coordination, construct the respiration microenvironment with suitable water vapor and oxygen permeability, so as to effectively inhibit the proliferation of microorganism on the surface of agaricus bisporus, and maintain its sensory quality.The composite film has significantly enhanced water stability, realizes the sustained release of gold nanoparticles, can effectively inhibit the microbial infection of agaricus bisporus after harvest.

A method for preparing bimodal nanocapsules includes: preparing a solution of mesoporous silica and deionized water, adding chloroauric acid solution and stirring, then adding sodium borohydride solution under ice bath stirring conditions to obtain gold nanoparticle-modified mesoporous silica; preparing a solvent of ultrapure water and gold nanoparticle-modified mesoporous silica, then sequentially adding a fluorescence quencher, a fluorescent molecule, and 4-mercaptophenylboronic acid to react separately to obtain bimolecularly modified nanoprobes; and mixing an adenosine-5′-triphosphate nucleic acid aptamer solution with the nanoprobes using ultrapure water as a solvent to obtain nucleic acid aptamer-encapsulated bimodal nanocapsules. This invention provides a simple, mild, environmentally friendly, and low-cost preparation method. The bimodal nanocapsules prepared by this invention can simultaneously monitor the levels of hydrogen peroxide and adenosine-5′-triphosphate (ATP) in cells using fluorescence and surface-enhanced Raman scattering (SERS) techniques, which can be used for early disease monitoring.

This invention discloses Au nanoparticles loaded with bimetallic compounds for photocatalysis and their preparation method, belonging to the field of photocatalytic materials technology. Preparation steps: S1: Tetrachloroauric acid, quaternary ammonium salt, and citric acid are added to a sodium borohydride solution and stirred at 25-120℃ for 1-3 hours to obtain solution A; solution B is prepared containing quaternary ammonium salt, tetrachloroauric acid, ascorbic acid, silver nitrate, and hydrochloric acid; solutions A and B are mixed and stirred at 25-50℃ for 1-15 hours to obtain Au nanoparticles; S2: Solution C is prepared containing quaternary ammonium salt, a first metal source, and ascorbic acid; solution D is prepared containing quaternary ammonium salt, a second metal source, NaOH, and ascorbic acid; Au nanoparticles are mixed with solution C and reacted at 40-80℃ for 1-5 hours; then the supernatant is removed by centrifugation, and solution D is added again, reacting for 1-5 hours to obtain Au nanoparticles loaded with bimetallic compounds. This invention enables controllable nanoparticle structure and allows for metal loading at different sites by adjusting synthesis parameters.

This invention provides a method for modifying Ti3C2T with nano-gold. x This invention relates to quantum dot composite SERS substrate materials, their preparation methods, and applications, belonging to the field of detection and testing technology. The invention involves etching Ti3AlC2 material to obtain Ti3C2T... x The material was diluted with ammonia and then crushed to obtain Ti3C2T. x Materials: Quantum dot suspension; Chloroauric acid solution was mixed with ascorbic acid, surfactant, and water to carry out a reduction reaction, yielding nano-gold sol; Ti3C2T x The quantum dot suspension was mixed with gold nanoparticle sol for composite formation, and the resulting gold nanoparticles were used to modify Ti3C2T. x Quantum dot composites were attached to a solid support to obtain Ti3C2T based on gold nanoparticles. x Quantum dot composite SERS substrate material. The composite SERS substrate material prepared by this invention achieves efficient detection of hydrophobic organic compounds and can be widely used in the field of biodetection technology, demonstrating strong practicality.

The invention belongs to the field of biomedical materials, and discloses an antibacterial heterojunction nano-material for repairing diabetes infected wounds and a preparation method and application thereof.The preparation method of the antibacterial heterojunction nano-material comprises the following steps that 1, Ti3C2 nanosheets are dispersed in deionized water, then a chloroauric acid aqueous solution and a BSA aqueous solution are added, stirred and mixed to be uniform, and Ti3C2 nanosheets are obtained; then adding a NaBH4 aqueous solution to carry out in-situ reduction, and after reduction is finished, carrying out centrifugal treatment to obtain a Ti3C2 nanosheet deposited with Au particles; and (2) dispersing the Ti3C2 nanosheets deposited with Au particles in an alcohol solvent, then adding a 4-mercaptophenylboronic acid solution for modification, and after modification is completed, centrifuging, washing and drying to obtain the antibacterial heterojunction nanomaterial. According to the material, the antibacterial activity is enhanced through glucose-triggered material structure transformation cascading, the problem of wound bacterial biofilm breeding is effectively solved, and diabetes infected wound repair is promoted.

This invention discloses Ti3C2T x This research focuses on the aerogel growth of gold nanomaterials using (MXene) / functionalized graphene quantum dots and their applications, belonging to the field of organophosphorus pesticide analysis and detection technology. Citric acid, serine, and arginine were dissolved in deionized water and heated to obtain citrate-arginine-serine quantum dots; Ti3A1C2(MAX) was then etched using lithium fluoride and hydrochloric acid to obtain Ti3C2T. x (MXene); To Ti3C2T x A quantum dot solution was added dropwise to generate a microgel; a gold nanoparticle growth solution was added dropwise to the microgel, followed by incubation with chloroauric acid and then a reducing agent. After the reaction was complete, the mixture was centrifuged, washed, and vacuum dried to obtain graphene quantum dot-functionalized gold nanoparticles. This invention utilizes the superior conductivity of Ti3C2T... x Gold nanoparticles were grown on functionalized graphene quantum dot microgels and used as electrocatalytic active materials. An electrochemical sensor was constructed using aptamers as recognition molecules to detect the organophosphorus pesticide methamidophos.

This invention discloses a method for preparing a multi-level micro / nano-structured composite material for nuclear radiation detection, relating to the field of nuclear radiation detection technology. Specifically, it utilizes gold-sulfur self-assembly technology to modify the surface of a gold nanoparticle core with boron-containing molecules, obtaining a functionalized gold nanoparticle core. This core is then used as a seed, with chloroauric acid as the gold source, to grow a gold nanoshell. Finally, silver nitrate is used as the silver source to deposit a silver nanoshell in situ, resulting in a multi-level micro / nano-structured composite material. This multi-level micro / nano-structure uses gold nanoparticles as the core, boron-containing molecules as the neutron detection medium, the gold nanoshell as the surface-enhanced Raman scattering (SERS) carrier, and the silver nanoshell as the gamma-ray detection medium. This material possesses both neutron and gamma-ray detection capabilities, and the neutron response of the boron-containing molecules and the gamma-ray response of the silver nanoshell can be quantitatively measured using SERS and LSPR spectroscopy, respectively. This enables efficient discrimination of mixed radiation field doses and has broad application prospects in the field of nuclear radiation detection.

This invention relates to the field of nanomaterials technology, and discloses a method for preparing and applying gold nanoparticles synthesized using microbial extracellular polymers (EPS). The method uses methylbazin exopolymers (EPS) as a green reducing agent and stabilizer, reacting them with chloroauric acid in an aqueous phase. By adjusting the EPS concentration, pH, and temperature, gold nanoparticles (EPS-Au NPs) can be synthesized in a controlled manner. The resulting nanoparticles exhibit high crystallinity and good dispersibility, and demonstrate ultra-high activity in catalyzing the reduction of 4-nitrophenol, with a TOF value reaching 485.53 h⁻¹. ‑1 This invention is superior to many traditional catalysts and has good cycle stability. The process of this invention is green and controllable, and the resulting catalyst has promising applications in wastewater treatment and other fields.

The application discloses a high-stability small-particle-size nucleic acid-gold nanocomposite and a synthesis method thereof, and belongs to the technical field of functional nanomaterial preparation, and the synthesis method comprises the following steps: under the conditions of heating and stirring, a reducing agent solution is added into a boiling chloroauric acid aqueous solution in batches, a solution of a functional nucleic acid molecule with a PolyA sequence at the terminal is added after boiling again, an acetic acid solution is added when the color of the reaction system is changed from light pink or light purple to dark, and the high-stability small-particle-size nucleic acid-gold nanocomposite is prepared after the reaction is completed; the application provides a brand-new "one-pot" synthesis strategy, discards complicated multi-step separation operation, realizes the synthesis of gold nanoparticles and the surface nucleic acid functionalization of the gold nanoparticles in one step in the same reaction system, the preparation process is simple, the product is uniform in particle size, good in dispersity, free from a plasmon resonance absorption peak, and has excellent long-term storage stability without depending on any exogenous polymer protective agent.

This invention discloses a method for preparing an Au@WO3:Yb,Er / CdS composite catalyst for photocatalytic hydrogen production, belonging to the field of photocatalytic materials technology. The method of this invention first involves preparing rare earth nitrates from Yb2O3 and Er2O3, chloroauric acid, and (NH4)6H2W... 12 O 40 xH2O was mixed to form precursor solution I, which was then dropped onto a polystyrene opal template and calcined to obtain Au@WO3:Yb,Er inverse opal material. This material was then added to precursor solution II, which was made of CdCl2·2.5H2O and Na2S·9H2O. After stirring, washing, and drying, Au@WO3:Yb,Er / CdS composite catalyst was obtained. This catalyst combines the advantages of single Au@WO3:Yb,Er and single CdS. Under the synergistic effect of Au, WO3:Yb,Er and CdS, carrier recombination was suppressed, light absorption was improved, and hydrogen evolution yield was increased.

This invention belongs to the field of biomedical technology, specifically relating to a chitosan-modified gold nanoclusters and its preparation method. The preparation method provided by this invention includes the following steps: S01: glutathione is added to a chloroauric acid solution and stirred to react; S02: under nitrogen protection, a reducing agent is slowly added dropwise to prepare a crude GSH-AuNCs reaction solution; S03: the crude GSH-AuNCs reaction solution is purified by dialysis; S04: a chitosan solution is prepared; S05: the purified GSH-AuNCs solution is reacted with the chitosan solution to obtain the chitosan-modified gold nanoclusters. This invention provides a two-step low-temperature modification method, first synthesizing CSH-AuNCs core nanoparticles under mild reaction conditions, resulting in high product reproducibility and a more complete original structure; then, chitosan is modified through electrostatic interaction to form CS-GSH-AuNCs clusters, providing higher controllability of the surface modification layer and enabling precise control of particle surface charge and size.

This invention discloses a surface-enhanced Raman spectroscopy (SERS) substrate material, its preparation method, and its applications. The method includes the following steps: S1, extracting and pretreating silk material; S2, immersing the silk material in a chloroauric acid solution; S3, heating and reducing a mixture of silk material and chloroauric acid solution; S4, removing the silk material, washing, and drying to obtain the SERS substrate material. The SERS substrate of this invention significantly improves the detection sensitivity and selectivity for mucin through optimized nanoparticle distribution and porous structure. This invention uses silk fiber waste as a bio-substrate and utilizes sericin and fibroin for in-situ reduction, effectively reducing the use of toxic chemicals and improving the biocompatibility and environmental friendliness of the substrate. The preparation method of this invention is simple, low-cost, suitable for mass production, and convenient for on-site testing in resource-limited environments.

The application belongs to the technical field of biological medicine and nanomaterials, and particularly relates to a nano system for targeted photothermal-chemotherapy synergistic treatment of abdominal aortic aneurysm as well as a preparation method and application thereof. The system is a mesoporous polydopamine-coated gold nanorod cluster (AuM) nanoparticle co-loaded with one or more traditional Chinese medicine ingredients and modified by c(RGDfK) cyclic peptide. The preparation comprises the following steps: taking chloroauric acid and dopamine hydrochloride as raw materials, synthesizing AuM in the presence of a reaming agent and a template agent by a one-step method; further loading a large amount of drugs in the mesopores to obtain drug-loaded nanoparticles; and finally grafting a targeting peptide on the surface of the nanoparticles to obtain the final product. The system has the characteristics of targeting macrophages and smooth muscle cells, NIR-Ⅱ photothermal conversion and photothermal response drug release. The in-vitro and in-vivo experimental results show that the system can realize local photothermal treatment and precise drug release under NIR-Ⅱ light, and inhibit aortic dilation through various cell behaviors, thereby providing a nano preparation with clinical transformation potential for precise treatment of abdominal aortic aneurysm.

This invention discloses a gold nanoparticle enhancer for magnetic resonance elastography, its preparation method, and its application, belonging to the field of medical imaging technology. The preparation method includes dissolving trisodium citrate in deionized water to obtain solution A, then adding chloroauric acid solution to generate solution B. When the temperature of solution B drops to 90°C, an equal amount of chloroauric acid solution is added to form solution C and stirred. An equal amount of chloroauric acid solution is added again and stirred to form solution D. After the reaction is complete, ultrafiltration, centrifugation, and washing are performed to obtain the gold nanoparticle enhancer. This invention achieves the controllable synthesis of the gold nanoparticle enhancer. The preparation method is simple, easy to operate, and has good reproducibility. The obtained gold nanoparticle enhancer has uniform particle size, good dispersibility, and excellent stability, making it easy to scale up production. More importantly, the gold nanoparticle enhancer prepared by this invention has excellent low toxicity and good biocompatibility.

The application discloses a high-purity gold refining process in the technical field of gold refining, which comprises the following steps: after gold raw materials are made into pieces, the gold is dissolved in a hydrochloric acid-sodium chlorate system in steps and then is dissolved in aqua regia for strengthened final solution, gold-containing solutions are combined, a magnetic multi-tooth coordination inorganic modified material is added for deep adsorption of impurities, a purified chloroauric acid solution is obtained through separation under an applied magnetic field, high-purity gold is prepared through reduction precipitation, acid boiling and impurity removal and smelting in an inert atmosphere. The magnetic multi-tooth coordination inorganic modified material is prepared by using ferroferric oxide as a magnetic core, coating a silica layer and a porous zinc-aluminum layered double metal oxide shell layer in sequence, and then performing surface modification through amination, and is prepared through covalent grafting of ethylenediaminetetraacetic dianhydride and nitrilotriacetic acid and coordination anchoring. Through the cooperation of step-by-step gold dissolution and magnetic multi-tooth coordination adsorption, the gold dissolution rate and deep removal of impurities are effectively considered, the operation is simple, the adsorption material can be separated and recycled under an applied magnetic field, and the product has high purity.

This invention discloses chiral gold nanoflowers, their preparation method, and applications. The method includes the following steps: S1, preparing a growth solution; adding deionized water, chloroauric acid aqueous solution, and ascorbic acid aqueous solution to a hexadecyltrimethylammonium bromide aqueous solution and mixing to obtain a growth solution; S2, introducing chiral molecules; injecting chiral molecules L-cysteine ​​or D-cysteine ​​into the growth solution and mixing to obtain a chiral induced growth system; S3, seed-induced growth; adding a gold nanorod solution to the chiral induced growth system and mixing; allowing the reaction to stand, and growing to obtain crude chiral gold nanoflowers. The preparation method uses gold nanorods as seed crystals, and the excessive growth of gold nanoflowers is induced in situ by chiral cysteine ​​molecules. The reaction conditions are mild, the operation is simple and easy to control, the product exhibits significant chiral characteristics, and high reproducibility. Chiral gold nanostructures can expand applications in catalysis, biosensing, chiral recognition, optical devices, and other fields, showing good application prospects and practical application value.

This application provides a submicron spherical gold powder and its preparation method, relating to the field of precious metal powder preparation technology. The preparation method first prepares a chloroauric acid solution using pure gold, adjusting its pH to 2-3 for later use. A first dispersant is added to the chloroauric acid solution to form a gold source solution. Then, a mixed solution of a reducing agent and an acidic additive is added to the gold source solution in one step. After reacting for 10-20 minutes, a second dispersant is added. After the reaction is complete, the powder is treated with a cleaning agent and vacuum dried to obtain well-dispersed submicron spherical gold powder. This application allows for controllable preparation of gold powder particle size distribution by adjusting the amount of acidic additive added to the reducing solution. This application requires no temperature control, has a simple process flow, and a short reaction time, and can prepare submicron spherical gold powder with good single-particle dispersion and a particle size distribution of 0.3-1 μm, suitable for the 3D printing field.

The application discloses a preparation method of a surface-enhanced Raman spectrum substrate for detecting sulfonamide drug residues, and belongs to the technical field of Raman detection. In the application, a small-particle-size gold nanoparticle is formed by co-exfoliation of a chloroauric acid aqueous solution and purple phosphorus, and is loaded on the surface of exfoliated layered purple phosphorus (VP); subsequently, gold ions are continuously provided by the chloroauric acid aqueous solution, and the diameter of the small-particle-size gold nanoparticle is expanded by L-ascorbic acid reduction, so as to finally form a VP (AuNPs / VP) composite substrate modified by gold nanoparticles (AuNPs). The AuNPs / VP composite substrate prepared in the application can detect residues of various sulfonamides, and is a sensitive, reliable and effective identification and detection means.

This invention discloses a method for preparing sodium gold sulfite solution for electroplating, comprising the following steps: S1, reacting gold powder with a hydrochloric acid-hydrogen peroxide mixture at 70-90℃ to obtain a chloroauric acid solution, wherein the reaction time is 1-5 h; S2, adjusting the pH of the obtained chloroauric acid solution to 5.5-6.5, then introducing hydrogen sulfide gas to generate a black gold sulfide precipitate, which is then filtered and washed; S3, slowly adding hydrogen peroxide to the gold sulfide precipitate obtained in step S2, strictly controlling the pH of the reaction system at 3-5, and adding the resulting yellow transparent solution dropwise to sodium sulfite while controlling the pH at 10-11 to obtain a colorless sodium gold sulfite solution; S4, purifying the colorless sodium gold sulfite solution obtained in step S3 by electrodialysis to remove impurities, ultimately obtaining a sodium gold sulfite solution with low chlorine content.

This invention provides gold nanoparticles and their preparation method, comprising the following components by mass percentage: chloroauric acid 5-5%, quercetin 1-3%, chitosan 0.5-2%, hexadecyltrimethylammonium bromide 0.1-0.5%, and ultrapure water 92-93%; wherein the degree of deacetylation of chitosan is ≥90%. This invention uses natural quercetin instead of sodium borohydride as a reducing agent, reducing toxic byproducts and conforming to green chemistry principles; by using chitosan (degree of deacetylation ≥90%) as a stabilizer, it imparts positive charge properties to the particles, enhancing cellular uptake efficiency and reducing toxicity.

This invention provides a composite film containing ergothioneine and gold nanomaterials. The composite preservation film is obtained by mixing and stirring a complex prepared from ergothioneine and gold nanoclusters with a mixture prepared from chitosan and polyvinyl alcohol, followed by molding and drying. The preparation process is as follows: S1, ergothioneine solution, chloroauric acid solution, and ultrapure water are mixed, the pH is adjusted, the mixture is stirred, and then placed on a shaker overnight. After dialysis and freeze-drying, AuNSs-EGT is obtained; S2, chitosan is dissolved in an aqueous acetic acid solution to obtain a chitosan solution; polyvinyl alcohol is dissolved in deionized water to obtain a polyvinyl alcohol solution; the two solutions are mixed, a plasticizer is added, and the mixture is stirred to obtain a CS-PVA mixture; S3, AuNSs-EGT is added to the CS-PVA mixture and mixed evenly. After ultrasonic treatment, the mixture is poured into a mold and dried to obtain the composite preservation film. The composite film prepared by this invention possesses excellent physical and chemical properties and can be used in the field of food preservation.

The application relates to the fields of material preparation and chemical analysis, in particular to a kind of preparation of MnO2 / AuOs composite material and method for detecting Pb 2+ Using MnO2 / AuOs. MnO2 / AuOs preparation includes MnO2 nanosheet, Au seed, AuOs, MnO2 / AuOs preparation. NaOH is added to manganese acetate solution, stirred, centrifuged, and the precipitate is dispersed in 2-mercaptoethanol aqueous solution to obtain MnO2 nanosheet. Gold seed is obtained by the reaction of tetrachloroauric acid and NaBH4, K2OsCl6 and ascorbic acid are added to the gold seed solution to obtain AuOs. AuOs is added to the MnO2 nanosheet solution, stirred to obtain MnO2 / AuOs composite material. Different concentrations of Pb 2+ are added to the MnO2 / AuOs composite material, acetic acid-sodium acetate buffer solution, 3,3',5,5'-tetramethylbenzidine solution and H2O2 solution are added, and Pb 2+ is detected by ultraviolet spectrophotometer. The MnO2 / AuOs composite material has peroxidase-like activity, Pb 2+ can form an alloy with gold in the material in the presence of 2-mercaptoethanol, thereby enhancing the peroxidase-like activity, so the composite nanomaterial can be used for detecting Pb 2+ .

The application provides an inorganic / polymer multi-component photocatalyst for antibiosis and a preparation method and application thereof. The method comprises the following steps: preparing a porous sheet layer graphite phase carbon nitride with negative electricity and a polyethylene imine modified reduced graphene oxide with positive electricity respectively; adopting an electrostatic assembly method to obtain a polyethylene imine / reduced graphene oxide / graphite phase carbon nitride "sandwiched" assembly structure; introducing chloroaurate ions into the obtained assembly structure; and utilizing the reducing property of the polyethylene imine to penetrate gold nano ions into the surface interface of the assembly structure, so as to obtain a multi-component photocatalyst of the polyethylene imine / reduced graphene oxide / graphite phase carbon nitride / gold nano particle composite. The multi-component photocatalyst is prepared by the technical means of electrostatic assembly and polyelectrolyte reduction, is efficient and low in energy consumption, can be used for efficiently generating hydrogen peroxide in situ, and can further obtain effective photocatalytic antibiosis performance, and has a wide application prospect in the field of antibacterial materials.

The application discloses a method for preparing low-oxygen-content high-purity gold from regenerated crude gold, which comprises the following steps: (1) adding hydrochloric acid into the regenerated crude gold and blowing air into the regenerated crude gold to pre-leach impurities under certain conditions; (2) dissolving, diluting and filtering the gold material after pre-leaching of impurities by using hydrochloric acid and chlorine gas to obtain a chloroauric acid solution; (3) adding appropriate ferric chloride into the chloroauric acid solution, adjusting the pH value by using sodium hydroxide solution, standing, filtering and obtaining a pure gold solution; (4) reducing the gold solution after impurity removal by adding hydrogen peroxide solution, filtering and washing to obtain sponge gold; and (5) refining and deoxidizing the sponge gold in a smelting and refining device, and obtaining low-oxygen-content high-purity gold after cooling. The method has the advantages of simple technological process, good impurity removal effect and easy control of the reaction process, and the high-purity gold prepared by the method has a purity of greater than 99.999% and an oxygen content of not more than 1 ppm.