363 results about "Silver nanoparticle" patented technology

The invention relates to double-layer integrated asymmetric viscous hydrogel as well as a preparation method and application thereof, and belongs to the technical field of hydrogel. The invention relates to a preparation method of double-layer integrated asymmetric viscous hydrogel, which comprises the following steps: adding natural macromolecular polysaccharide and a polymeric monomer into a salt solution, stirring at room temperature, then adding an initiator and a cross-linking agent, stirring and polymerizing to obtain the double-layer integrated asymmetric viscous hydrogel. Through a one-pot method, a salt component is introduced into a hydrogel system, and the hydrogel has a double-layer structure with asymmetric viscosity under the salting-out action; in addition, the hydrogel is doped with a carbon nanotube with the surface modified by polydopamine and silver nanoparticles, so that the mechanical property and the conductivity of the hydrogel are remarkably improved. The preparation method provided by the invention is simple, is suitable for various hydrogel systems, has good universality and is easy to popularize and apply.

A membrane includes a polysulfone-based support, a polydopamine (PDA) layer disposed on a surface of the polysulfone-based support, and a silver / polydopamine (Ag / PDA) composite layer disposed on a surface of the polydopamine layer. The polysulfone-based support has a pore size of up to 600 nanometers (nm). The Ag / PDA composite layer contains core-shell structure particles and spherical particles. The core-shell structure particles have a silver nanoparticle core and a polydopamine shell. The spherical particles are silver-decorated polydopamine particles. The membrane can at least partially separate an Erichrome Black T (EBT) dye from an EBT dye / salt containing mixture by rejecting the EBT dye and allowing the EBT dye / salt containing mixture to pass through the membrane.

The invention provides a method for detecting an external vesicle marker through high-flux nano plasma exciting light immune color development, and belongs to the technical field of human extracellular vesicles. After a serum sample is subjected to centrifugal treatment, the serum sample and a CD81 capture antibody substrate are incubated, and the particle size distribution of the vesicles is monitored in real time; a zwitterionic polymer modified gold nanoparticle LAM detection probe and a polyethylene glycol modified silver nanoparticle LprG detection probe are prepared to be specifically combined with a vesicle surface antigen, a chromogenic enhancement solution is adopted to induce a plasma resonance signal, and full-hole scanning imaging is carried out; and constructing a double-layer game optimization model to cooperatively optimize the detection sensitivity and the signal stability, carrying out weighted summation on normalized signals of the particle size subgroups to obtain comprehensive detection signal intensity, comparing the comprehensive detection signal intensity with a threshold value, and outputting a final judgment result. The technical problem that quantitative accuracy is affected by signal intensity deviation caused by vesicle particle size difference in outer vesicle marker detection is solved.

The invention relates to the technical field of functional coatings of medical instruments, in particular to a temperature-sensitive response type sodium polyacrylate catheter leakage-proof coating, a preparation method and application thereof, and the coating is of a three-layer composite structure. And the bottom bonding layer adopts a polydopamine modified silane coupling agent system, contains silver nanoparticles, has the thickness of 5-15 microns, and ensures strong bonding and antibiosis of the substrate. The middle functional layer is a three-dimensional cross-linking degree gradient interpenetrating network polymer, is composed of a plurality of monomers and nano materials, and is 50-100 [mu] m in thickness, the cross-linking degree of the middle functional layer is gradually increased from inside to outside, gradient transition of mechanical properties is achieved, the outer protective layer is composed of a copolymer, is 3-8 [mu] m in thickness, and provides excellent anti-fouling and biocompatibility. The coating is endowed with strong adhesive force, gradient mechanical property and surface stability, the sodium polyacrylate component absorbs water and expands in urine to form sealing, and the expansion degree of the sodium polyacrylate component is regulated and controlled by the pH value and ionic strength of the urine.

The invention belongs to the technical field of gas analysis, and relates to a surface-enhanced Raman scattering flexible substrate material as well as a preparation method and application thereof. The surface-enhanced Raman scattering flexible substrate material comprises a three-dimensional network structure and silver nanoparticles, the three-dimensional network structure is composed of hydroxypropyl methyl cellulose nanofibers, the silver nanoparticles are wrapped in the hydroxypropyl methyl cellulose nanofibers, and the silver nanoparticles are of a polyhedral structure. The surface-enhanced Raman scattering flexible substrate material is used for detecting thiol compounds in a solution, and the detection limit can reach 10 <-19 > M level; after the surface of the silver nanoparticle is modified with the probe, the material can detect trace substances in exhaled air. In addition, after the material is stored for 6 months at room temperature, the SERS signal intensity attenuation is less than or equal to 4%, and the relative standard deviation detected by 20 random sites is only 4.04%.

The invention discloses a construction method and application of an SERS (Surface Enhanced Raman Scattering) sensor for detecting Mn < 7 + >. Belongs to the field of detection application, and the construction method of the SERS sensor for detecting Mn < 7 + > comprises the following steps: uniformly mixing an ABTS solution, a to-be-detected solution containing Mn < 7 + > and a silver nanoparticle solution, adding an acid solution to adjust the pH value of a reaction system, and reacting for 1-3 minutes. The SERS sensor for detecting Mn < 7 + > is applied to detection of heavy metal Mn < 7 + >. According to the method disclosed by the invention, by virtue of specific selection of the ABTS on Mn < 7 + > and addition of silver which has extremely high characteristics on SERS detection, convenient and rapid trace detection on Mn < 7 + > is realized. The selective reaction material explored by the invention is used for trace detection of heavy metal Mn < 7 + > by utilizing an SERS technology, and has important significance in application to actual life.

The application discloses a kind of microscale single particle quantitative analysis method and system based on nano-silver signal enhancement, it is related to spectral analysis technical field, the method includes: using laser-induced breakdown spectroscopy system to the carbon black particle target sample is carried out spectral data acquisition, obtains target full spectrum data and is pretreated, and then obtains target spectral data matrix;Variable importance measurement algorithm and continuous projection algorithm are used to the variable in the target spectral data matrix is screened, and target variable is obtained;Target variable is input into carbon black particle metal content prediction model, and the content of metal element in carbon black particle target sample is obtained.The application can quickly and accurately determine the content of metal element in carbon black particle target sample.

The invention discloses a lignin-derived carbon fiber-based sodium metal battery negative electrode material which is prepared by the following steps: performing granulation and melt-blowing on lignin to obtain lignin fibers, performing pre-oxidation and carbonization treatment on the lignin fibers to obtain lignin-derived carbon fibers, soaking the lignin-derived carbon fibers in a silver nitrate saturated solution, taking out the lignin-derived carbon fibers, and drying to obtain the lignin-derived carbon fiber-based sodium metal battery negative electrode material. And carrying out flash burning treatment to obtain the silver nanoparticle / lignin derived carbon fiber composite material. The invention discloses a composite electrode plate for a sodium metal battery, which is prepared by the following steps: grinding a lignin-derived carbon fiber-based sodium metal battery negative electrode material into a short fiber shape, uniformly mixing with polyvinylidene fluoride and N-methyl pyrrolidone to prepare slurry, coating a negative current collector with the slurry, and cutting into pieces to obtain the lignin-derived carbon fiber-based composite electrode plate. The lignin-derived carbon fiber-based sodium metal battery negative electrode material has a three-dimensional interpenetrating network structure, has a high specific surface area, enables an electric field to be uniformly distributed, inhibits dendritic crystal growth, and is suitable for a sodium metal battery system.

The invention discloses a gel microneedle loaded with silver nanoparticles and a preparation method and application thereof.The extract nano-silver (AB-AgNPs) is prepared through a green synthesis strategy, a drug-loaded microneedle system is constructed based on carboxymethyl chitosan-vanillic aldehyde-polyvinyl alcohol (CMCS-Va-PVA) composite gel, the AB-AgNPs prepared through the technology are uniform in particle size and stable in dispersion, and the drug-loaded microneedle has the advantages that the drug-loaded microneedle is good in drug-loaded performance and good in drug-loaded performance; the crystal has a typical face-centered cubic crystal structure and metal state Ag0 characteristics; the gel microneedle has good mechanical strength and forming effect, the AB-AgNPs and the gel matrix are stably combined through hydrogen bonds, the chemical properties are kept unchanged, and the system has broad-spectrum efficient bacteriostatic activity and biocompatibility; an in-vitro experiment proves that the green synthesized gel microneedle loaded with the silver nanoparticles has a remarkable capability of promoting the healing of L929 cell tissues; a rat wound experiment proves that the gel microneedle can regulate and control an inflammatory factor network and promote cell migration and tissue regeneration, healing of common and infected wounds is remarkably accelerated, and the wound residue ratio in 9 days is as low as 2.7% and 10.9% respectively.

The invention discloses a hydrophobic gas diffusion electrode loaded with silver nanoparticles and application of the hydrophobic gas diffusion electrode in electrocatalytic carbon dioxide reduction, and belongs to the technical field of electrocatalysis. The hydrophobic gas diffusion electrode comprises a gas diffusion layer and a catalyst layer sprayed on the gas diffusion layer; the catalyst layer comprises a silver nanoparticle catalytic material, a first ionomer and a second ionomer; wherein the first ionomer is a fluororesin ionomer, and the second ionomer is a quaternized polysulfone ionomer. A system for preparing CO by reducing CO2 through electro-catalysis is constructed, the system comprises an MEA electrolytic cell, a cathode, an anode and an anion exchange membrane, and the cathode adopts the hydrophobic gas diffusion electrode loaded with the silver nanoparticles. The preparation method is mild in preparation condition and environmentally friendly, the modified hydrophobic gas diffusion electrode has high hydrophobicity, efficient conversion of CO2 can be achieved under the high current density, FECO can reach 96.5% under the high current density, and excellent catalytic performance is shown.

The invention relates to the technical field of immunochromatography analysis, and discloses a signal enhancer of a colloidal gold immunochromatography rapid detection card and a preparation method thereof, the signal enhancer comprises a silver ion solution, a thiourea-ascorbic acid synergistic reducing agent, a pH buffer system and a surfactant stabilizing system, the signal amplification is realized by catalyzing and depositing silver nanoparticles on the surface of colloidal gold, the operation is simple and convenient, one-time addition is realized, and the reaction is completed within 5-10 minutes; the sensitivity is improved by 5-10 times, and the specificity is higher than 98%; the stability is excellent, and the storage time is 12 months at 4 DEG C; various colloidal gold rapid detection cards are universally compatible; compared with the prior art, the colloidal gold immunochromatography rapid detection card has the advantages that the cost is controllable, the single detection is increased by 0.3-0.5 yuan, and the colloidal gold immunochromatography rapid detection card is particularly suitable for ultra-sensitive detection of small molecular substances in the field of food safety, for example, the detection limit of malachite green reaches 0.1 microgram per liter, the detection limit of fipronil reaches 0.5 microgram per liter, and the application range of the colloidal gold immunochromatography rapid detection card is obviously expanded.

The invention belongs to the field of antibiotic analysis and detection, and discloses a quinolone drug SERS (Surface Enhanced Raman Scattering) detection method based on an improved silver nano-substrate and a spectral angle matching model. An improved Lee-Meisel method is adopted to synthesize silver nano sol with precisely controlled particle size, molecular adsorption is realized by utilizing electrostatic interaction of a positively charged quinolone drug and negatively charged silver nano particles, and a high-density Raman enhanced hot spot is formed after an agglomeration agent is added; the SERS spectrum is collected at the excitation wavelength of 785 nm and the integral time of 10 s, qualitative distinguishing of drugs is achieved by combining a spectrum angle matching model, and quantitative detection is achieved by constructing a standard curve through the linear relation between the characteristic peak intensity and the drug concentration logarithm. The detection limit of the four drugs is as low as 1.03-1.16 ppb, the classification accuracy rate reaches 100%, the method is obviously superior to existing similar methods, the detection matrix range is wide, such as animal food and dairy products, and universality and high sensitivity are both considered.

The invention relates to a preparation method of a nano waterproof fabric. According to the method, ellagic acid is introduced in the self-polymerization process of dopamine for in-situ reduction, a polydopamine bonding layer and a silver nanoparticle anchoring layer are synchronously constructed on the surface of nano silicon dioxide, and then perfluorodecyltriethoxysilane is catalyzed by silver nanoparticles for a regioselective click chemical reaction, so that the nano silicon dioxide is obtained. The multifunctional bionic core-shell particles with catalytic activity and super-hydrophobicity are prepared. The particles are compounded with a fluorosilicone copolymer containing dynamic disulfide bonds, a fluorosilicone polymer containing boric acid ester groups and a tannic acid-metal complex to form a double-dynamic cross-linking finishing agent system. After a fabric is subjected to ultraviolet / ozone pretreatment, discontinuous polydopamine nanodot arrays are formed on the surfaces of fibers through short-time dopamine polymerization to serve as catalytic sites, then interface priority crosslinking is triggered by utilizing the sites, and finally, dynamic keys are driven to cooperatively exchange through ultraviolet light fixation and heat treatment, so that the intelligent dynamic waterproof membrane is formed.

The application discloses a preparation method of a VP@UiO-66-NH2 / Ag NPs composite SERS chip and application thereof in A beta protein detection, and is characterized by comprising the following steps: synthesizing a VP-graphite paper base by a chemical vapor transport method on a surface of a graphite paper to obtain a VP-graphite paper base; synthesizing a UiO-66-NH2 layer on the surface of the VP-graphite paper base by a solvothermal method to obtain a VP@UiO-66-NH2 composite base; and finally, placing the composite base in an ion sputtering instrument, uniformly sputtering silver nanoparticles on the surface of the composite base, taking out the composite base, and obtaining the VP@UiO-66-NH2 / Ag NPs composite SERS chip, wherein the VP@UiO-66-NH2 / Ag NPs composite SERS chip has the advantages of high sensitivity, good stability and uniformity, controllable preparation process, low cost, application in Alzheimer's disease biomarker detection, high specificity in identification and quantitative analysis of A beta 40 and A beta 42 proteins, fast response and good stability.

This invention provides a simple synthesis method for Fe-Ag / CMP nanopolymers with catalase-like activity and their application in hydrogen peroxide detection, belonging to the field of bioanalytical technology. The method of this invention includes the following steps: (1) preparing a 4-hydroxyethylpiperazine thiosulfonic acid (HEPES) standard buffer solution; (2) adding cytidine monophosphate (CMP) to the solution obtained in step (1) and stirring until the CMP is fully dissolved. Then, under vigorous stirring, ferric nitrate aqueous solution and silver nitrate aqueous solution are added sequentially, at which point the colorless solution turns pale yellow; (3) transferring the mixed solution obtained in step (2) to a centrifuge tube, centrifuging at 12000 rpm for 8 min to collect the precipitate, washing it three times with distilled water, and finally adding 4 mL of distilled water to obtain a 1 mg / mL Fe-Ag / CMP suspension. This invention utilizes CMP as a biological ligand and Ag... + Fe 3+ Simultaneous coordination, and the reducing amino groups on CMP can directly transfer Ag... + In situ reduction to silver nanoparticles (AgNPs) led to the one-step synthesis of a bimetallic Fe-Ag / CMP nanopolymer with hydrogen peroxide-like nanozyme activity, enabling the detection of hydrogen peroxide.

The invention discloses a preparation method of an MF (at) NH2 (at) Ag SERS (Surface Enhanced Raman Scattering) sensor for detecting paraquat and diquat, belongs to the field of nano material synthesis and spectral analysis, and solves the problems that a traditional detection method is complicated in process and cannot detect pesticides and free radicals thereof at the same time, and a traditional SERS substrate is poor in enhancement effect and low in stability. The preparation method comprises the following steps: firstly segmenting melamine foam, cleaning and drying, soaking in hydrochloric acid, soaking in a polyethyleneimine aqueous solution to modify amino, drying, soaking in a silver nitrate solution for ultrasonic treatment, adding a sodium borohydride solution under an ice bath, stirring and reducing, and finally cleaning and drying to obtain the sensor. The sensor takes three-dimensional melamine foam as a support, silver nanoparticles are uniformly loaded on the surface of the three-dimensional melamine foam, paraquat, aquacide and free radicals thereof are enriched through electrostatic interaction based on a localized surface plasma resonance principle, and Raman signal enhancement is realized. The detection limit is 10 <-9 > mol / L, the signal stability and repeatability are excellent, the applicability to actual water sample detection is good, the detection of other pesticides can be expanded, and the method is suitable for on-site rapid trace detection.

The application discloses an electronic skin-oriented conductive silver paste and a preparation method and application thereof, and relates to the technical field of flexible printed electronic materials.The raw materials of the electronic skin-oriented conductive silver paste include flaky silver powder, silver nanoparticles, thermoplastic polyurethane elastomer, acrylic elastomer, PEDOT:PSS microgel dispersion, (3-glycidylpropoxy)trimethoxysilane, polydiallyldimethylammonium chloride, hexanedial modified dopamine copolymer, (3-aminopropyl)triethoxysilane, methacryloyloxypropyltrimethoxysilane, cellulose acetate, modified polyurea thixotropic agent, hydrogenated castor oil, ethylene glycol ether acetate, dibasic acid ester, leveling agent and water.The electronic skin-oriented conductive silver paste has the advantages of good electrical performance, good mechanical-electrical stability, good anti-electromigration and sweat corrosion resistance, and can still maintain dendrite-free and low drift under long-term coupling of sweat and bias, and is suitable for electronic skin.

The invention relates to the technical field of environment-friendly materials, in particular to an environment-friendly degradable composite material which comprises a natural cellulose base material, modified nanofiller, a bio-based plasticizer, a cross-linking agent and a coating layer of chitosan and silver nanoparticles. The preparation method comprises the steps of mixing dispersion, ultrasonic treatment, hot press molding, surface coating, ultraviolet activation and the like. By optimizing components and process parameters, the defects of an existing material in the aspects of degradation performance, functional diversity and long-term stability are overcome, good degradability, excellent antibacterial performance and stability under high-temperature and high-humidity conditions of the material in different environments are achieved, and the material is suitable for various scene requirements.

The invention discloses an electrochemical aptamer sensor for detecting kanamycin as well as a preparation method and application of the electrochemical aptamer sensor, and belongs to the technical field of electrochemical biosensing analysis. According to the invention, a gold electrode assembled with a kanamycin aptamer with sulfydryl is taken as a sensing interface, a target molecule kanamycin is combined to the sensing interface, and a silver nanoparticle-zirconium-based metal organic framework material signal probe is combined with kanamycin on the sensing interface, so that the sandwich type kanamycin electrochemical aptamer sensor is constructed. The kanamycin electrochemical aptamer sensor prepared by the invention has relatively high sensitivity, relatively low detection limit and relatively wide detection range, the detection limit of the sensor is 0.085 aM, and the detection range is 0.1 aM <-1 > nM. The electrochemical aptamer sensor prepared by the invention is used for quantitative detection of kanamycin, and has the advantages of good stability, strong specificity, good reproducibility and the like.

The invention relates to the technical field of coatings, in particular to a graphene modified polyurethane coating with an electromagnetic shielding function. The coating is composed of deionized water, a graphene modified polyurethane emulsion, silver nanoparticles and an auxiliary agent, a synergistic modification system of hydroxylated graphene and p-hydroxybenzoic acid is introduced in a polyurethane prepolymerization stage, an organic-inorganic synergistic network with good interface compatibility is formed, the conductivity and electromagnetic shielding effect of the coating are remarkably improved through a formed compact conductive path, and meanwhile the flexibility and adhesive strength of polyurethane are kept. The coating is compact in structure, high in adhesive force, good in conductive continuity and excellent in electromagnetic shielding effect, and can be widely applied to the field of electromagnetic protection of electronic equipment shells, communication devices and aerospace equipment.

This invention belongs to the field of SERS detection technology and relates to the application of an Ag / Bi4O5Br2 / Ni-Fe double hydroxide composite SERS substrate in the detection of CV in wastewater. First, a Bi4O5Br2 / Ni-Fe double hydroxide is prepared, and silver nanoparticles are loaded onto its surface using a liquid-phase chemical reduction method. This material combines the LSPR effect of silver nanoparticles with the interfacial coupling and multiple active sites of the Ni-Fe double hydroxide, enabling the regulation of interfacial charge transfer and enhancing molecular adsorption. Utilizing the excellent adsorption and enrichment properties of Bi4O5Br2, a highly efficient charge transport system is synergistically constructed from multiple components, improving the SERS chemical enhancement effect and amplifying the CV Raman signal. This invention overcomes the shortcomings of weak signals and insufficient stability of single substrates, achieving sensitive detection of trace CV in water. The substrate preparation process is simple, environmentally friendly, and highly practical, showing broad application prospects in the field of trace CV analysis in aquatic environments.

The application discloses a preparation method of honey-mediated silver nanoparticle / attapulgite composite antibacterial material, which comprises the following steps: dissolving natural honey in water to form a honey aqueous solution under stirring, dispersing attapulgite powder into the honey aqueous solution to obtain a uniform mixed solution, adding silver nitrate aqueous solution dropwise into the mixed solution, adjusting the pH of the mixed solution to 8-9, and continuously stirring the mixed solution at room temperature for 3-6 hours; and centrifuging, washing and drying the obtained product to obtain the silver nanoparticle / attapulgite composite antibacterial material. The active components in the honey are used as a reducing agent and a stabilizer, the silver nanoparticle / attapulgite composite antibacterial material is synthesized by one-step method, the preparation process is green, simple and efficient; the natural attapulgite is used as a carrier, on the one hand, the generation process of the silver nanoparticles is regulated, and the technical problem of effectively reducing the agglomeration of the silver nanoparticles is solved; and on the other hand, the biological activity is synergistically enhanced, so that the silver nanoparticles can play a more efficient antibacterial role and the application safety is improved.

The invention provides an insecticide delivery preparation based on binary synergistic nanoparticles and a preparation method thereof, an IMI (at) AgNPs (at) CMSNs compound is prepared, and the binary system remarkably overcomes the drug resistance of cotton aphid to imidacloprid by integrating silver nanoparticles (AgNPs) and mesoporous silica nanoparticles (MSNs).

The invention discloses a medicinal glass bottle and a forming process thereof, and belongs to the technical field of medical materials, the medicinal glass bottle comprises a glass bottle body and a composite coating on the inner wall of the glass bottle; the forming process comprises the following steps: 1) pretreating the glass substrate; 2) constructing a composite layer; 3) constructing a barrier layer; and 4) cross-linking inerting and post-processing. According to the inner wall coating designed by the invention, a sandwich structure is adopted, and strong adhesive force of a bottom layer is realized through amino silane; the silver nanoparticles are anchored in situ by using a branched polyethyleneimine network, so that stable antibiosis is realized; a compact zwitterionic polymer brush is constructed on the outermost layer through surface-initiated polymerization, and a super-hydrophilic and biologically inert surface is provided; and finally, through cross-linking inerting treatment, the stability and safety of the coating are greatly improved. The problems of medicine adsorption, microorganism breeding, coating instability and the like of a traditional packaging material are solved, and a safe and reliable novel solution is provided for medicine packaging.

This invention provides a long-lasting antibacterial spray, its preparation method, and its application. The antibacterial spray comprises a polyphenol adhesion component, metal ions, auxiliary polyphenols, a network stabilizer, and water. The metal ions form a dynamically reversible coordination network with the polyphenol adhesion component; the metal ions include silver ions and zinc ions. In this invention, the silver nanoparticles may undergo surface oxidation or coordination dissociation processes in the polyphenol network environment, thus serving as a potential source of supplementary silver ions, contributing to a smoother ion release behavior and achieving long-lasting antibacterial action through ion-nano synergy. This invention utilizes the synergistic effect of silver and zinc ions to improve the physical stability of the system. By introducing a small amount of silver nanoparticles as "solid-phase nodes" in the polyphenol network, the structural stability and resistance to mechanical damage of the antibacterial system are improved without significantly increasing the total silver release.

This invention belongs to the interdisciplinary field of biomedical engineering, materials science, and tissue engineering, and discloses a multifunctional hydrogel with switchable mechanical and adhesive properties based on temperature triggering, its preparation method, and applications. The invention consists of acrylic acid, gelatin, hexadecyltrimethylammonium bromide, polydopamine nanoparticles loaded with silver nanoparticles, and water. This invention not only exhibits excellent adhesion and mechanical properties to skin tissue but also possesses switchable mechanical and adhesive properties, achieving durable and repeatable adhesion. The temperature-triggered hydrogel prepared by this invention is simple to process, low in cost, and introduces no toxic chemicals. It can achieve a close fit at body temperature and natural detachment at low temperatures, driven by temperature, and maintains excellent adhesion properties even in complex environments, thus promoting the development of intelligent medical multifunctional wound dressings.

The invention discloses a biosensor based on an ultraviolet light triggered bio-barcode release technology (OBCA) and construction and application of the biosensor. The biosensor comprises nucleic acid functionalized silver nanoparticles, nucleic acid functionalized magnetic beads and a CRISPR (clustered regularly interspaced short palindromic repeats) / Cas12a detection system, the DNA bar code modified on the surface of the silver nanoparticle contains a light cleavable linker, a CRISPR / Cas12a activation sequence and a target capture sequence I, and a DNA capture probe containing a target capture sequence II is fixed on the surface of the magnetic bead through biotin-streptavidin action. During detection, target miRNA mediates two capture sequences to form a sandwich compound, after magnetic separation and thermal denaturation elution, 365nm ultraviolet radiation releases DNA bar code fragments, and the Cas12a trans-cleavage fluorescence quenching reporter probe is activated to generate a signal. According to the method, nucleic acid amplification and reverse transcription are not needed, the detection limits of miR-21, miR-155 and mi-210 respectively reach 158.94 aM, 763.56 aM and 197.82 aM, single-base mismatch and precursor miRNA can be distinguished, the serum sample detection result is highly consistent with that of RT-PCR, and the method is suitable for high-sensitivity quantitative detection of miRNA.

The invention relates to nano-composite low-temperature wind power lubricating grease and a preparation method thereof, and belongs to the technical field of lubricating grease. The invention aims to solve the technical problems of large viscosity change, poor friction surface adsorbability and difficulty in forming a high-strength thick friction film of the existing lubricating grease at low temperature. The lubricating grease comprises the following components in percentage by mass: 0.10%-5% of copper or silver nanoparticles, 0.10%-3.00% of ionic liquid, 5.00%-15.00% of a thickening agent, 1.50%-5.00% of a saponification reactant, 0.10%-0.50% of an antioxidant, 0.01%-1.00% of an antirust agent, 0.10%-0.50% of a demulsifying agent and the balance of base oil, wherein the sum of the mass percentages of the components is 100%. Through the synergistic effect of the nano-particles and the ionic liquid, a composite lubricating film with strong adsorption and high bearing capacity is formed on the surface of a friction pair under the extremely cold condition, so that the lubricating oil still has excellent antifriction and antiwear performance and lubricating stability in the low-temperature environment of minus 40 DEG C or below, and is specially used for long-acting lubrication of wind power bearings, motors and transmission equipment.

The invention discloses a photoresist composition based on metal nanoparticles and application of the photoresist composition. The photoresist composition comprises metal nanoparticles, a photosensitizer, an anti-diffusion agent and a photoresist solvent, wherein the metal nanoparticles are silver nanoparticles, copper nanoparticles and gold nanoparticles. The photoresist composition has good film-forming property and excellent patterning imaging capability, photoetching patterns with different resolutions can be obtained through ultraviolet, electron beam or extreme ultraviolet exposure, and the formed patterns have good conductivity after being subjected to heat treatment and can be directly used for processing micro-nano devices.

The invention relates to a photochromic lens with a photochromic dye grafted nanoparticle composite film layer and a preparation method of the photochromic lens, and belongs to the technical field of optical lenses. The photochromic lens comprises a lens base material, a priming coat, a photochromic dye grafted nanoparticle composite film layer and a protective layer which are sequentially stacked from bottom to top, wherein chemical bond grafting is formed between the photochromic dye and the surfaces of the gold / silver nanoparticles through sulfydryl or carboxyl at the tail end of a molecule of the photochromic dye. The localized surface plasmon resonance effect of the covalent grafting structure and the nanoparticles synergistically solves the bottlenecks of easy agglomeration, low loading capacity and slow response of the dye in the traditional technology. The lens disclosed by the invention has the characteristics of extremely fast color-changing response, high color fading efficiency, high mechanical strength, good environmental stability and the like, and the comprehensive performance and the service life of the color-changing lens are remarkably improved and prolonged.