145results about How to "Strong magnetic response" patented technology

The invention relates to a preparation method and an application of a magnetic fluorescent nanoparticle with a shell-core structure. Firstly, a silica magnetic microsphere with a shell-core structure is prepared by using one or more than one of nanoparticles of Fe3O4, gamma-Fe2O3, MeFe2O4 (Me=Co, Mn, Ni), metal Ni, Co, Fe, and alloy Fe-Co, Ni-Fe as the inner core, and coating a silica shell, and then a fluorescent material (a chelate of Eu3+, Sm3+, Dy3+, Tb3+ and the like) is absorbed on the silica shell. Then, a layer of silica is coated on the surface to improve the stability of the fluorescent magnetic microsphere, and to prevent agglomeration and fluorescent material leakage. A lot of rare earth fluorescent materials are wrapped in the shell layer, so the fluorescence intensity signal of a prepared sample is greatly increased. The nanoparticle has dual functions of enrichment and marking, and has wider application prospects in the biomedical field.

The invention discloses a preparation method of magnetic/gold nano particles. The preparation method comprises the following steps: firstly adopting a co-precipitation method to prepare the magnetic Fe3O4 nano particles; polymerizing the dopamine in-situ on the surfaces of the magnetic particles to obtain Fe3O4 nano particles modified by the poly dopamine; introducing polyphenol and amino groups to the surfaces of the Fe3O4 nano particles; absorbing the nano gold seeds on the surfaces of the modified magnetic particles through the static action; adopting the nano gold which is absorbed on the surfaces of the magnetic particles as the seed, adopting the polyphenol on the surfaces of the magnetic particles as a reducing agent, gradually adding the chloroauric acid liquid to gradually produce the gold layers on the surfaces of the magnetic particles to obtain the core-shell magnetic/gold nano particles. The nano particles have good water dispersion and strong magnetic respond performance. The diameters of the nano particles are 30-100 nanometers, the saturation magnetization is 30.1-38.7emu/g, and the nano particles are superparamagnetic. The nano particles have wide application prospect on the fields of targeted drug controlled release, thermal therapy, separation of protein and enzyme, etc.

The invention relates to a preparation method of magnetic mesoporous molecular imprinted hybrid silicon spheres. The preparation method comprises the following steps: firstly preparing Fe3O4 magnetic microspheres by adopting a solvothermal method, then coating mesoporous silica on the surfaces of the Fe3O4 magnetic microspheres through a sol-gel method and finally synthesizing the magnetic mesoporous molecular imprinted hybrid silicon spheres on the surfaces of the magnetic mesoporous silicon spheres by utilizing an RAFT (reversible addition-fragmentation chain transfer) molecular imprinting technology. The prepared magnetic mesoporous molecular imprinted hybrid silicon spheres can be used for selectively removing alkylphenol in drinking water. The preparation method disclosed by the invention has the advantages that the preparation method of the magnetic mesoporous molecular imprinted hybrid silicon spheres is reasonable in process and easy to implement; when the materials are used for removing alkylphenol type endocrine disruptors, the materials have good chemical stability and reusability and are easy to realize active adsorption, identification and separation against the alkylphenol; and according to the preparation method, the properties of magnetic mesoporous microspheres and a molecular imprinted polymer can be combined into a whole, the using efficiency of the molecular imprinting technology can be greatly improved and the range of molecular imprinting applications can be further expanded.

The invention relates to a preparing method ofa nano-magnetic polymer composite microsphere, which comprises the following steps: preparing a hydrophilic Fe3O4 magnetic liquid particle by using a chemical co-precipitation method; dissolving initiating agents and emulsifying agents by weight part into ionized water to prepare water phase, adding the hydrophilic Fe3O4 magnetic liquid particle and adding a monomer to obtain nano-magnetic seed emulsion through polymerization; dissolving initiating agents by weight part into ionized water, adding the nano-magnetic seed emulsion and then adding a monomer to obtain nano-magnetic polymer composite microsphere emulsion through polymerization; the emulsifying agents are sodium lauryl sulfate, sodium dodecyl sulfate or sodium dodecyl benzene sulfonate; the initiating agents are potassium peroxydisulfate, ammonium persulphate or sodium peroxydisulfate; the initiating agents are potassium peroxydisulfate, ammonium persulphate or sodium peroxydisulfate; the hydrophobic monomer is styrene or methyl methacrylate or a mixture of the styrene and the methyl methacrylate; the nano-magnetic polymer composite microspheres prepared by adopting a seed emulsion polymerization method have the superparamagnetism, have stronger magnetic responsiveness, have no uncoated magnetic particle and contain magnetic polymer microspheres and are narrow to distribute.

The invention belongs to the field of advanced nanometer composite material technique, in particular to a magnetic inorganic hollow composite micro-ball and a preparation method thereof. The method of the invention comprises the steps as follows: firstly, by a solvent volatilization method, the co-deposition of magnetic nanometer particles and polymer micro-balls is generated so as to lead the magnetic nanometer particle to be filled into the gap of the polymer micro-ball; subsequently, by a nanometer pouring method, inorganic oxide sol is filled into the residual space of the polymer micro-ball gap; by inorganic oxide sol hydrolysis, the inorganic oxide enwraps the magnetic nanometer particle and covers around the polymer micro-ball; furthermore, the polymer micro-ball is removed by sintering so as to obtain the metal oxide composite hollow micro-ball with the shell doped with magnetic nanometer particles. The micro-ball can be dispersed in the water solution by supersonic oscillation. The magnetic hollow ball has stronger magnetic saturated strength and higher mechanical stability, has wide application on the aspects of biology separation, medicament transport, and catalyst load, etc. The method of the invention is simple, the raw material is easy to be obtained and the method of the invention is applicable for amplification production.

The invention relates to a magnetic thermometer nm particle with biocompatibility, which has biocompatibility, and double response properties of magnetism and thermometer property, and the particle diameter thereof is 20 to 60 nm, and the magnetic responsibility is strong, and magnetic saturation intensity is 10.0 to 27.0 emu/g. The synthetic method of the magnetic thermometer nm particle with biocompatibility comprises: firstly, adopting chemical coprecipitation method to prepare magnetic Fe3O4 nm particle, and using silane coupler to hold surface modification, and then using the modified magnetic Fe3O4 nm particle as a seed, and having polyreaction with dextran, N-isopropyl acrylamide, finally obtaining the magnetic thermometer nm particle with biocompatibility. The magnetic thermometer nm particle with biocompatibility synchronously has double responses of magnetism and thermometer property, and has wide application prospect in the fields of drug release, protein and enzyme separation.

The present invention relates to a magnetic nano crystal which is prepared with the ''one-port'' method and can be highly dissolved and steadily dispersed in the biological buffer liquid. Under the condition that the biocompatibility polymer exits or the biocompatibility polymer, the small-molecule amine with alkyl chain, carboxyl acid or alcohol exist together, the metal precursor is decomposed with high temperature in the high boiling point nonpolar or high boiling point weak-polar solvent for preparing the high-crystallinity magnetic nano crystal with different kind, different dimension and different shapes. The technical method adopted by the invention has the characters of simple technique, easy operation. The grain diameter of the magnetic nano crystal prepared with the technique has the advantages of uniformity, controllability, high crystallinity, strong magnetic response and good biocompatibility. Most important, the dry powder of the obtained magnetic nano crystal still represents excellent dissolvability after placing in the biological buffer liquid for a long time. Therefore, the biocompatibility magnetic nano crystal prepared by the technical method has the characters of easy storing and transportation, and is suitable for large-scale and commercial production.

The invention relates to a preparation method for magnetic nanoparticles coated with highly ordered mesoporous carbon. The method comprises the following steps of: making the magnetic nanoparticles as an inner core; fully coating the outer layer of the magnetic inner core with an organic template agent by static or hydrophobic interaction; and carbonizing at a high temperature to form the magnetic nanoparticles coated with the channel height ordered mesoporous carbon through self-assembly coating of an organic polymer precursor which can be used for forming mesoporous carbon and the organic template agent on the surface of the magnetic inner core. The magnetic nanoparticles coated with highly ordered mesoporous carbon, which is prepared according to the method, can be applicable for the fields such as bioseparation, medicine transfer, magnetic resonance imaging radiography and catalysis.

The invention discloses a preparation method of a high-performance gold-shell magnetic microsphere and surface enhanced Raman scattering (SERS) application of the high-performance gold-shell magnetic microsphere. A substrate uses a Fe3O4 microsphere of 100-1,000 nanometers as a core to provide magnetism, polymer polyethyleneimine (PEI) is used as a multi-functional sandwiched layer to improve the dispersibility of the magnetic microsphere and absorb gold seeds of 3-5 nanometers, and finally, a uniform and stable gold shell is prepared by a seed reduction method. The preparation method comprises the following steps of firstly, modifying Fe3O4 microsphere with the PEI to form a polymer protection layer, and absorbing the gold seeds of 3-5 nanometers by means of strong positive electricity of polyethyleneimine; secondly, rapidly reducing the uniform and stable gold shell under an ultrasonic condition by a seed growing method and by taking hydroxylamine hydrochloride as a reducing agent; thirdly, adding high-concentration povidone (PVP) to improve the dispersibility of particles; and finally, obtaining the high-performance gold-shell magnetic microsphere. The invention also discloses application of the gold-shell magnetic microsphere prepared by the method in SERS detection. The gold-shell magnetic microsphere is high in magnetic response, good in dispersibility and stable in structure, has excellent SERS performance and can be used for SERS detection and analysis on various pollutants, pesticide residue, pathogenic microorganism and the like in a solution.

The invention discloses a preparation method of a magnetic composite SERS substrate with core-shell-satellite three dimensional structures. The substrate comprises magnetic composite microspheres which employ silver-shelled magnetic bead (Fe3O4@Ag) microspheres as the cores, cation polymer polyethylenimine (PEI) shell layers as particle inner intervals, and gold nanoparticles (AuNPs) as satellite particles. The preparation method comprises the following steps: the 400nm Fe3O4 microspheres are modified with PEI, 3nm colloidal gold is adsorbed, the microspheres are used as seeds, and Fe3O4@Ag microspheres whose silver shells are continuous are reduced as cores; self-assembly time of PEI is controlled, and PEI forms 1.5nm interval layers (Fe3O4@Ag-PEI) on the surfaces of Fe3O4@Ag microspheres; finally 50nm AuNPs are adsorbed on the surface of Fe3O4@Ag-PEI, and the magnetic composite SERS substrate (Fe3O4@Ag-PEI-Au) with the core-shell-satellite three dimensional structures is formed. The invention also discloses the magnetic composite SERS substrate with the core-shell-satellite three dimensional structures, which is prepared by the method; the substrate has the advantages of good magnetic induction, good dispersibility, stable structure, and multiple hot spots; the substrate can be directly applied to SERS detection of various micromolecule pollutants, pesticide residues, illegal additives of foodstuff, and the like.

The invention discloses an application of magnetic nanoparticles in nucleic acid extraction, wherein the magnetic nanoparticles are magnetic Fe3O4 nanoparticles with surfaces coated with a polydopamine coating. The magnetic nanoparticles provided by the invention have superparamagnetism, high environmental stability and monodispersity, the polydopamine coating coating on the surfaces of the nanoparticles is rich in amino group and hydroxyl group, can realize high-efficiency adsorption for nucleic acid, improves the efficiency and quality for adsorbing nucleic acid of existing magnetic nanoparticles, can realize high-efficiency rapid extraction of nucleic acid, does not need blood processing when being applied to human whole blood extraction, and thus is applicable to clinical disease genediagnosis and treatment. The preparation method of the magnetic nanoparticles disclosed by the invention effectively simplifies the preparation process of the magnetic nanoparticles used as a nucleicacid adsorbent, lowers the preparation process and is suitable for preparation and application of magnetic nanoparticles.

The invention discloses a multi-target magnetic immunochemiluminescence micro-fluidic chip detection platform and method, and belongs to the field of rapid diagnosis in vitro. The detection platform comprises a sample introduction hole, a liquid flow connection channel, a target detection area, a liquid waste port, a cleaning liquid pool and a luminescent liquid pool; the target detection area comprises a coating area, a mixing area and capture areas, which are connected in sequence; the detection method comprises the following steps: injecting a sample into the sample introduction hole, so that the sample flows by the liquid flow connection channel, redissolves an antibody in the coating area and forms a target compound to be captured, causing the remaining sample to flow by the downstream coating area to form the target compound, capturing the target compound, until target molecules in the sample are captured separately; and then, removing free non-target molecules by using cleaningliquid, releasing the luminescent liquid, causing the same to flow by the capture areas in sequence, and performing signal collection. The platform integrates sample introduction, magnetic absorption,high-efficiency capture and separation and fast detection, and can detect multiple targets on one chip at the same time, and the multi-target magnetic immunochemiluminescence micro-fluidic chip detection platform has the characteristics of convenient operation, fast detection, low cost, etc.

The invention provides a viscoelastic nano-magnetic fluid for improving the crude oil recovery ratio of a tight reservoir, and a preparation method thereof. The viscoelastic nano-magnetic fluid is composed of surface modifier-modified Fe3O4 particles used as nano-magnetic particles and a viscoelastic surfactant solution used as a carrier liquid; the mass concentration of the surface modifier-modified Fe3O4 particles is 0.5-10 wt.%; and the viscoelastic surfactant solution is prepared by dissolving an anionic surfactant and a counter ion agent in water. The invention further provides the preparation method of the viscoelastic nano-magnetic fluid. The nano-magnetic fluid has the advantages of viscoelasticity, good stability, narrow particle size distribution, strong lipophilicity of the magnetic particles, strong magnetic response, cheap preparation raw materials and simple preparation process, is suitable for industrial production, and can be used in the field of tight reservoir crude oil exploitation to improve the crude oil recovery efficiency.

The invention belongs to the technical field of magnetic particle preparation, and discloses a method for preparing biocompatible coating controllable core-shell type magnetic particles. The method comprises the following steps: anchoring methylacrylic acid to the Fe3O4 particle surface through a simple coordination reaction between methylacrylic acid MAA and unsaturated iron ions on the Fe3O4 nano-particle surface to form a polymerizable structure Fe3O4-MAA; adding konjac glucomannan, methylacrylic acid, a crosslinking agent, initiator and template, directly polymerizing through a graft copolymerization method to form coating controllable core-shell type magnetic particles with biocompatibility. The method is simple in process and low in cost, and the product can be used in carriers of target magnetic field drug release materials, magnetic resonance imaging contrast agents, magnetic molecularly imprinted polymer and the like.

The invention relates to a bimetallic cobalt-based core-shell material and a preparation method and application thereof. A core of the bimetallic cobalt-based core-shell material is a magnetic metal Co, and a shell of the bimetallic cobalt-based core-shell material is a non-magnetic metal Ag or Cu; a shape of the bimetallic cobalt-based core-shell material is fibrous or spherical, a fiber diameteris 1.3 to 36 micrometer, and a spherical diameter is 1 to 7.3 micrometer; an atomic ratio of Co to Cu is 0.25 to 21.6, and the atomic ratio of Co to Ag is 59.8 to 74.8; a saturation magnetization strength ranges from 62.2 to 159.9 emu/g<-1>. The bimetallic cobalt-based core-shell material adopts an in-situ metal replacement method and has a microwave absorption characteristic of broadband and high absorption, wherein an effective frequency band width of which the reflectivity is less than or equal to -10dB is 5.1-7.76GHz; a bandwidth less than or equal to -20dB is 2.32-16.0GHz; a maximum reflection loss ranges from -52.5 dB to -19.7 dB. The bimetallic cobalt-based core-shell material has the advantages of simple process, easy industrial popularization, excellent material performance and good application prospect in the fields of catalysis, electrode materials, microwave absorption, high-density magnetic recording materials, sensors and the like.

The invention belongs to the technical field of advanced nano-composite materials and particularly provides an inorganic magnetic three-dimensional ordered macro-porous (3DOM) material and a preparation method thereof. The preparation method comprises the following steps: firstly, dispersing magnetic nano-particles and polymer microspheres in a solution, so that the gaps formed by arranging the polymer microspheres in an ordered manner can be filled with the magnetic nano-particles by the evaporation self-assembly of the solution; then, filling the remaining gaps of the polymer microsphere/magnetic nano-particle composite material with inorganic oxide sol by the nano-casting method, so that the ordered composite structure can be fixed; and finally, calcining in the presence of nitrogen to remove the polymer microspheres, so as to obtain the 3DOM material. The magnetic 3DOM material has the advantages of higher magnetic response and higher stability, and the 3DOM material is provided with ordered macro-pores which are communicated on a three-dimensional basis. Therefore, the invention is widely applicable in the aspects of bio-separation, drug delivery, catalytic loading and the like. The preparation method is simple and the materials are easily available. Therefore, the invention is suitable for large-scale production.

The invention discloses a preparation method and SERS application of monodispersed silver-shell magnetic microspheres. In a base, 400 nm Fe3O4 microspheres are taken as cores to provide magnetism, 50 nm SiO2 shells are taken as hydrophilic sandwich layers to improve the dispersibility of the microspheres, and complete and uniform silver shells are prepared with chemical plating and seed reduction methods. The preparation method comprises the following steps: enabling the 400 nm Fe3O4 microspheres to be covered with the 50 nm SiO2 shells with an improved Stober method, and then carrying out sensitization on the SiO2 shells through SnCl2, so that a great deal of Sn<2+> are adsorbed; washing the magnetic microspheres with deionized water, after the SnCl2 is completely removed, and using a 40 mM silver-ammonia solution to perform kernelization on Fe3O4@SiO2 under an ultrasonic condition, so that a large quantity of Ag seeds are generated in an in situ manner; finally using a seed growing method, and under high-concentration PVP protection, using formaldehyde and stronger ammonia water to reduce the complete and uniform Ag shells so as to form the monodispersed silver-shell magnetic microspheres. The invention also discloses application of the silver-shell magnetic microspheres prepared through the method in SERS detection, the monodispersed silver-shell magnetic microspheres are high in magnetic responsiveness, good in dispersibility, stable in structure and extremely high in enhancing effect, and can be directly used for SERS detection of various micromolecular pollutants, pesticide residues, serum, cancer biomarkers and the like under a solution system.

The invention discloses a high-selectivity magnetic dye adsorbent and a preparation method thereof. The preparation method comprises the following steps: preparation of magnetic nano-Fe3O4; preparation of nano-Fe3O4-SiO2; surface amino modification of nano-Fe3O4-SiO2; bromination modification of nano-Fe3O4-SiO2-NH2; preparation of nano-Fe3O4-SiO2-PGMA (polyglycidyl methacrylate); and Lysine modification of nano-Fe3O4-SiO2-PGMA. The adsorbent is larger in specific surface area and rich in bisexual activated adsorption sites; high-selectivity separation can be performed on an organic dye such aslemon yellow and methylene blue; the adsorbent is higher in adsorption capacity and high in adsorption rate; due to the characteristic of good magnetic response, cyclic regeneration of a material isensured, and secondary pollution to water bodies can be prevented, and therefore, the adsorbent has a considerable application prospect in the aspect of treatment of water pollution caused by the organic dye.