1036 results about "Superparamagnetism" patented technology

Disclosed are thermotherapeutic compositions for treating disease material, and methods of targeted therapy utilizing such compositions. These compositions comprise a) stable single domain magnetic particles; b) magnetic nanoparticles comprising aggregates of superparamagnetic grains; or c) magnetic nanoparticles comprising aggregates of stable single magnetic domain crystals and superparamagnetic grains. These compositions may also comprise a radio isotope, potential radioactive isotope, chemotherapeutic agent. These methods comprise the administration to a patient's body, body part, body fluid, or tissue of bioprobes (energy susceptive materials attached to a target-specific ligand), and the application of energy to the bioprobes so as to destroy, rupture, or inactivate the target in the patient. Energy forms, such as AMF, are utilized to provide the energy. The disclosed methods may be useful in the treatment of a variety of indications, including cancers, diseases of the immune system, central nervous system and vascular system, and pathogen-borne diseases.

Polymeric nanoencapsulation methods, which combine sonication and nonsolvent temperature induced crystallization, are provided. The steps include (a) providing active agent nanoparticles having an average diameter between about 5 and about 100 nm; (b) treating said active agent nanoparticles (e.g., a superparamagnetic material) with an anionic surfactant to form modified active agent nanoparticles; (c) mixing the modified active agent nanoparticles with a solution of a polymer in a solvent at a first temperature, which is greater than the melting temperature of the polymer and less than the boiling point of the solvent to form a first mixture, said mixing comprising the use of sonication; (d) mixing a non-solvent with the first mixture to form a second mixture, the non-solvent being a non-solvent for the solvent and for the polymer and having a boiling point greater than the melting temperature of the polymer; (e) sonicating the second mixture to form an emulsion; and (f) cooling the emulsion to a second temperature and at a rate effective to precipitate polymeric nanoparticles comprising the polymer with the modified active agent nanoparticles dispersed therein.

Monodisperse colloidal nanocrystal clusters of magnetite (Fe3O4) with tunable sizes from about thirty to about three hundred nanometers have been synthesized using a high-temperature hydrolysis process. The colloidal nanocrystal clusters are capped with polyelectrolytes, and highly water soluble. Each cluster is composed of many single magnetite crystallites, thus retaining the superparamagnetic behavior at room temperature. The combination of superparamagnetic property, high magnetization, and high water dispersibility makes the colloidal nanocrystal clusters ideal candidates for various important biomedical applications such as drug delivery and bioseparation. The present invention is further directed to methods for forming colloidal photonic crystals from both aqueous and nonaqueous solutions of the superparamagnetic colloidal nanocrystal clusters with an external magnetic field applied thereto. The diffraction of the photonic crystals can be tuned from near infrared to visible and further ultraviolet spectral region by varying the external magnetic field.

This invention pertains to the use of spin resonance absorption heating as a therapeutic treatment method. It was a surprising discovery that electron spin resonance absorption of superparamagnetic (SPM) nanoparticles can be used as a heating method, more preferably as an in vivo heating method that can be utilized in a variety of therapeutic contexts.

The invention discloses a magnetic gold nanoparticle composite material, and a preparation method and application thereof. The preparation method comprises the following steps: synthesizing ferroferric oxide magnetic microspheres, adding tetraethoxyl silicon to implement hydrolysis and polymerization on the magnetic microsphere surfaces, adding N-(2-aminoethyl)-3-aminopropyltrimethoxysilane to obtain surface-modified double-amino-group Fe3O4 / SiO2 magnetic microspheres, and compounding the surface-modified double-amino-group magnetic microspheres with gold nanoparticles. The chelation action of the double amino groups is utilized to adsorb the gold nanoparticles more firmly; and the material combines the surface selectivity of the gold nanoparticles and the superparamagnetism of the magnetic nanoparticles, can extract benzopyrene in water, and can implement quick and efficient separation.

A superparamagnetism mesoporous silicon dioxide composite ball of the present invention and manufacture method thereof belong to nucleocapsid type technology field of magnetic nano particle. The shape of the composite ball is global; inner core being made of magnetic ferrite nano particle cluster, shell coating layer being made of mesoporous silicon dioxide; quality ratio of magnetic ferrite nano particle in particulate being 40-80%. Method of manufacturing has that producing magnetic ferrite nano particle is by using coprecipitation method; executing surface modification by adding oleic acid stirring; ultrasonic forming oil-in-water emulsion in the mix solution of ethyl orthosilicate and cyclohexane, cetyl trimethyl ammonium bromide as surfactant; ethyl orthosilicate hydrolytic condensation forming mesoporous silicon dioxide coating layer by adding ammonia spirit; finally taking off molding plate and getting products. Product of the invention has bigger specific surface area and stronger magnetic separation capacity, and has good dispersancy in water, and is further functionalization after being decorated at surface. The method of the present invention has simple process, and lower equipment requirement.

The invention discloses a magnetic carbon nanotube composite material and a preparation method and an application thereof. The preparation method comprises the following steps: adding FeCl3.6H2O to an ethylene glycol solution; then adding anhydrous sodium acetate and polyethylene glycol; adding a carboxylated multiwalled carbon nanotube; performing ultrasonic dispersion; adding hexamethylenediamine or ethanediamine; heating to 200-300 DEG C for reaction for 8-24h; and washing and performing vacuum drying to prepare the amino-modified magnetic Fe3O4-carbon nanotube composite material. The amino-modified magnetic Fe3O4-carbon nanotube composite material prepared by the invention is of nanoscale and superparamagnetism, can be stably dispersed in solutions, and can be quickly separated and enriched through a simple action of a magnetic field. As an adsorbent, the material is large in superficial area and has various active groups on the surface. The material can adsorb pigments from complex substrates through pi-pi electron interaction and hydrophobic effect of the carbon nanotube and can adsorb compounds such as organic acids and phenols through weak anion exchange effect of amino groups on the surfaces of magnetic nanoparticles.

The invention relates to a multifunctional double-layer core-shell structure magnetic nano particle. In the invention, a magnetic nano particle with a particle size of 1-300 nm is used as a core and coated with a double-layer shell consisting of a SiO2 layer with a thickness of 1-200 nm and a hydrolyzed silane coupling agent layer is 1-100 nm thick and comprises one or more multifunctional groups; the particle size and the shell layer thickness can be controlled through regulating the volumes, the weight ratios and the reaction time of the magnetic core, a silicon dioxide precursor, a silane coupling agent and a catalyst in a preparation process; the total particle size of the nano particle can be as small as 5-50 nm and as large as 700-800 nm; the nano particle can have superparamagnetism, paramagnetism and ferromagnetism according to the change of the magnetic core particle size; and one or more bioactive molecules can be connected into the shell layer of the magnetic nano particle or to the surface of the shell layer through a chemical method or a physical method. The invention also provides a preparation method of the multifunctional double-layer core-shell structure magnetic nano particle and application thereof. The particle preparation method has the advantages of simplicity, moderate condition, low cost and easy realization of industrial production. The nano particle can obtain different functions through connecting different bioactive molecules and can be applied to the fields of protein enrichment, biological detection, separation and purification, targeted drug carriers, cell imaging and medical imaging.

The invention relates to the field of microbial detection and discloses a method for rapid detection of enterobacter sakazakii. The method comprises the steps of: adding immunized superparamagnetism nanometer magnetic beads into a sample, adding a stabilizer, and incubating for 45-60min at 30-40 DEG C, wherein the magnetic beads are specifically bonded and enriched on microbial food-borne pathogenic bacteria, namely the enterobacter sakazakii, in the sample; and measuring spinning-spinning relaxation time and calculating a value deltaT2 by taking a bacteria-free sample as a blank control. The method disclosed by the invention has high specificity and sensitivity to the detection of the enterobacter sakazakii, is rapid, and is particularly suitable to detection of low-concentration enterobacter sakazakii, especially the enterobacter sakazakii in dairy products; in addition, the method is convenient and simple to operate and has good reliability and low requirement on assorted equipment.

The present invention provides the preparation process of super-paramagnetic polymer microsphere. The super-paramagnetic polymer microsphere consists of polyolefin polymerized with lipophilic olefin monomer and organic monomer with hydrophilic functional radical and coated nano magnetic grains of modified ferroferric oxide. The nano magnetic grains with one surface lipophilic layer can be well dispersed in organic matter to form magnetic fluid and dispersed inside polymer microsphere to obtain super-paramagnetism. The microsphere is regular and has size of 0.1-5 micron and has magnetic ferroferric oxide accounting for 0.5-40 wt% of the whole micro microsphere. The present invention has the advantages of simple preparation process, narrow microsphere size, regular appearance, high functional radical content, homogeneous magnetism, stable chemical performance and acid and alkali resistance.

In a production method for producing molded articles from fiber composites, superparamatic particles are selected which become coupled to an external alternating magnetic field. These superparamagnatic particles are added to a resin portion of a strip-shaped starting material further comprising reinforcing fibers. The strip-shaped starting material is then continuously advanced, and, while being advanced, heated by coupling-in an external alternating magnetic field to which the superparamagnatic particles in the resin portion become coupled. Next, the heated starting material is continuously molded into a molded article; and the resin portion in the molded particle is cured.

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.

Superparamagnetic (“SPM”) subunits of 1–30 nm average mean diameter (e.g. ferro fluid) subparticles are treated with a magnetically noninterfering substance capable of coating and covering them (e.g, BSA) and they spontaneously form agglomerates of about 100 nm to about 450 nm or higher average mean diameter and are then used to form complexes with target biological ligands such as viruses, contained in large volumes of liquid. The complexes are subjected to the gradient intensity of a strong magnetic field, and excess liquid is removed, where upon an immunochromatographic assay is conducted to determine the identity and / or amount of target ligand present, in which operation SPM particles that bonded to the ligand function as tags for ligand detection.

The invention discloses a method for preparing magnetic chitosan microspheres, relates to chitosan microspheres and provides superparamagnetic chitosan microspheres and a preparation method thereof. The magnetic chitosan microspheres comprise the following components in percentage by mass: 30 to 99 percent of chitosan and 1 to 70 percent of Fe3O4. The preparation method comprises: adding chitosan, a compound containing F3<3+> and a compound Fe<2+> into acidic solution to obtain solution A; and adding the solution A into alkaline aqueous solution to obtain solution B, and removing solidified and separated precipitates in solution B to obtain the magnetic chitosan microspheres. Compared with the conventional preparation method of magnetic chitosan microspheres, the preparation method of themagnetic chitosan microspheres is simple, easy to implement and low in cost and makes process simple. The size of the obtained magnetic chitosan microspheres is controllable, the Fe3O4 content is controllable and the magnetism is controllable.

The invention discloses a method for preparing carbon-coated superparamagnetic ferroferric oxide gel, which comprises: dissolving ferrocene and surfactant in an acetone solvent; adding solution of hydrogen peroxide into the solution to directly oxidize the ferrocene to synthesize polycrystal uniform magnetic nano balls under a low-temperature (180 to 240 DEG C) solvothermal condition; and allowing the polycrystal uniform magnetic nano balls to react in a magnetic field to prepare a magnetic linear nano material. The polycrystal uniform magnetic nano balls and nano chains are characterized in that: the particle size of the polycrystal uniform magnetic nano balls is limited to a narrow range and controllable; and the nano chains consist of uniform spherical particles and have high stability, and the inter-chain distance is controllable. The superparamagnetic polycrystal uniform nano ball and linear nano chain materials have high superparamagnetism and high chemical stability and gel stability and have promising application prospect in the field of biomedicine, nano self-assembly and the like; the nano balls are grafted by medicaments and can be used as medicament carriers; under the action of the magnetic field, the nano balls can be used as magnetic control photonic crystal; and the nano chains have a promising application prospect in the field of Bragg reflectors, magnetic probes, biomedicine and the like.

The invention belongs to the technical field of biomolecular labeling, in particular to a method for preparing an amino functional magnetic fluorescent coding microsphere with double-nucleocapsid structure. Two semiconductor quantum dots with different fluorescence colors and superparamagnetic ferric oxide nano-particles are embedded in a same silicon dioxide nano-particle in inverse microemulsion to form an amino functional magnetic fluorescent coding microsphere which has the granularity between 40nm and 100nm, high fluorescence intensity and high stability. The invention adjusts the fluorescence position and the intensity of the microsphere by changing the sort and the proportion of the quantum dots of different fluorescence colors and realizes different fluorescent coding. The addition of superparamagnetic ferroferric oxide ensures that the microsphere can gather and move fast in a targeted way under the action of an externally-applied magnetic field. Through amido modification on the surface of the microsphere, the invention can be widely applied to the fields of immunological test, nucleic acid hybridization, gene analysis, cell classification and imaging, etc.

The invention provides a magnetic zeolite imidazate metal organic skeletal material, preparation thereof and application to liquid phase condensation catalytic reaction, and the invention belongs to the field of magnetic zeolite imidazate metal organic skeletal material technology. The invention employs FeCl3.6H2O to prepare Fe3O4 core with superparamagnetism, and cetyl trimethyl ammonium bromide is used as a template, and sodium silicate is used as silicon source of SiO2 casing layer, and a SiO2 casing layer with meso pores is formed on Fe3O4 using supersonic wave, and template is roasted and removed under N2 after drying, and magnetic SiO2@Fe3O4 nanospheres are prepared. imidazate metal organic skeletal structure is formed on surface of magnetic core SiO2@Fe3O4 with Zn or Co metal ions and 2-methylimidazole or benzimidazole ligand by in-situ self assembly using supersonic wave, and the magnetic ZIFs@SiO2@Fe3O4 material is obtained. The ZIF material is used for liquid phase condensation reaction catalysis.

The invention relates to a preparation method and application of a magnetic silicon dioxide composite microsphere. Superparamagnetic ferroferric oxide nano particles of which the diameter ranges from 4 nm to 30 nm are prepared through a high-temperature pyrolysis method, a silicon dioxide shell of which the thickness ranges from 5 nm to 20nm covers the outer surfaces of the magnetic ferroferric oxide nano particles through a reverse microemulsion method, amination modification is conducted on the silicon dioxide surface, glutaraldehyde is used as a crosslinking arm, ligand protein is connected into, and protein separation is conducted through specific binding of ligand protein and target protein. The prepared magnetic microsphere is small in particle diameter and good in monodispersity, the composite microsphere with amine is large in specific surface area, nucleophilic addition is utilized, after the crosslinking arm glutaraldehyde is connected into, multiple kinds of ligand protein can be connected into, and then multiple kinds of target protein can be separated. The method is suitable for rapid separation and application of protein in biological samples, and has wide application prospect and great application value in the biomedical field and other fields.

The invention discloses a molecularly imprinted magnetic microsphere, a preparation method and an application thereof. The preparation method comprises the following steps: S1, adopting a coprecipitation method to prepare Fe3O4 nanometer particles; S2, adopting a microemulsion polymerization method to prepare a magnetic composite microsphere by virtue of the Fe3O4 nanometer particles; S3, adopting a sol-gel method to grow SiO2 on the surface of the magnetic composite microsphere to obtain a core-shell microsphere; S4, grafting C=C double bond on the surface of the core-shell magnetic microsphere; and S5, adopting a substitution template method on the surface, which is grafted with the C=C double bond, of the core-shell microsphere to carry out molecular imprinting operation to obtain the molecularly imprinted magnetic microsphere. DMIP (Dimethyl Isophthalate) prepared by the method provided by the invention has excellent superparamagnetism and excellent selectivity for target molecules.

A structure and method for improving the spatial resolution of a scanning probe microscope (SPM) tip, which has been coated with a layer of chemically-synthesized nanoparticles. The nanoparticles are either single-species or heterogeneous, such that the single-species nanoparticles can be either ferromagnetic, paramagnetic, superparamagnetic, antiferromagnetic, ferrimagnetic, magneto-optic, ferroelectric, piezoelectric, superconducting, semiconducting, magnetically-doped semiconducting, insulating, fluorescent, or chemically catalytic. The layer of nanoparticles is at least two nanoparticles thick, or alternatively, is a single layer of nanoparticles thick, or alternatively, is a single layer of nanoparticles thick and covers only the tip apex portion of the tip, or alternatively, only a single nanoparticle is affixed to the tip apex. Alternatively, the layer of nanoparticles is transformed into an electrically-continuous magnetic film by annealing at a high temperature.

The invention provides metal-organic framework materials with magnetic cores and preparation and application thereof, and belongs to the technical field of magnetic metal-organic framework materials. FeCl3 6H2O is adopted for preparing superparamagnetic Fe3O4 cores, cetyl trimethyl ammonium bromide is used as a template agent, sodium silicate is used as silicon sources of SiO2 shell layers, mesoporous SiO2 shell layers are formed on the surfaces of the Fe3O4 cores by adopting an ultrasonic wave method, the template agent is removed by roasting under protection of N2 after drying, and magnetic SiO2@Fe3O4 nanospheres are prepared. The SiO2@Fe3O4 nanospheres are used as cores, an in-situ self-assembly mesh structure IRMOFs is carried out on the surfaces of the SiO2@Fe3O4 cores through Zn metal ions and organic carboxylic acid ligands by adopting the ultrasonic wave method. The novel MOFs materials can be used as catalysts of liquid phase catalysis reaction, and also have application values in the aspects of adsorption, separation, biological medicine and the like.

The present invention relates to magnetic field-responsive fibers, which comprise magnetite particles and a polymeric matrix. The invention also provides methods of producing the same, in particular via electrospinning of a stably dispersed or monodispersed polymer solution, either aqueous or organic, comprising the magnetite particles, and applications thereof.

The invention provides superparamagnetic nano Fe3O4 particles synthesized through in-situ induction of chitosan hydrogels, relating to a method for synthesizing the superparamagnetic nano Fe3O4 particles. The invention solves the problems of serious aggregation of the nano Fe3O4 particles and the complicated method for inducing the chitosan into the surface of the Fe3O4 in the current nano Fe3O4 particles. The method of the invention is that: 1. the chitosan powder is added into dilute acid solution; 2. cross-linking agent is added to make the chitosan hydrogels; 3. the chitosan hydrogels are sequentially dipped in Fe3+ aqueous solution, water, Fe2+ aqueous solution and water, and a plurality of times of circular leaching are made so as to form the chitosan hydrogels that contains iron ions; 4. then basification treatment is carried out; 5. the hydrogels is dissolved or degraded again, and finally the black superparamagnetic Fe3O4 nano particles are obtained upon centrifugalization. The method of the invention requires simple technique and mild conditions and the equipment used in the method is simple and can be obtained easily, thereby mass production can be achieved. The average diameter of the particles is 15 to 25nm, and the particles distribute evenly with superparamagnetism.

The present invention features a method for preparing superparamagnetic iron particles by the in situ formation of these particles in a cross-linked starch matrix or by the formation of a superparamagnetic chitosan material. The superparamagnetic materials are formed by mild oxidation of ferrous ion, either entrapped into a cross-linked starch matrix or as a chitosan-Fe(II) complex, with the mild oxidizing agent, nitrate, under alkaline conditions. The present invention further features superparamagnetic iron compositions prepared by the method of the invention. The compositions of the invention are useful for the separation, isolation, identification, or purification of biological materials.

The invention relates to a weak magnetism detecting instrument based on time-resolved remanence relaxation detection and application thereof. The detecting instrument consists of a detecting unit provided with a sensitive element with high sensitivity therein, a sample bracket, a pulse magnetic field generator, a signal data acquiring and converting system and a computer. The working principle of the detecting instrument is that the superparamagnetic nanomaterial is magnetized via pulse by means of a pulse magnetic field with a steep edge, then a magnetism sensitive element with a high sensitivity is utilized to carry out track analysis on the remanence relaxation generated by the superparamagnetic nanomaterial under the action of the pulse magnetic field, and then a quantitative detection of superparamagnetic nanomaterial is realized. By means of the instrument, biological analysis with high sensitivity can be realized by combining with nano-particles or magnetic beads. The instrument and method of the invention have fast detection speed, low cost, high sensitivity and good stability, and are suitable for fields of biological analysis, disease diagnosis, food security, environment monitoring and the like.

A process for heating particle filled adhesive compositions by using an electrical, magnetic or electromagnetic alternating field. Nanoscale particles are employed having ferromagnetic, ferrimagnetic, superparamagnetic or piezoelectric properties. These particles more efficiently convert the electrical, magnetic or electromagnetic input into heat to cure the adhesive composition. With this process not only is the rate of cure accelerated but the various properties of the adhesive are less likely to be adversely affected.

This disclosure is directed at a microparticle for use in water treatment comprising a core layer; a shell layer, deposited on and encasing the core layer; and a photoactive layer surrounding the shell layer. The disclosure also provides a method for producing same.

Red blood cell-derived vesicles (RDV) as a nanoparticle drug delivery system. The RDV are smaller than one micrometer, capable of encapsulating and delivering an exogenous substance into cells. The substance may be at least one selected from the group consisting of fluorophores, nucleic acids, superparamagnetic compounds and therapeutic agents. The RDV are capable of delivering encapsulated substances into cells including stem cells. The delivered substance within the cell or stem cell may be traced or tracked using a suitable device either in vitro or in vivo.

A nanoparticle comprising an inorganic core and a polymerizable outer coating. The inorganic core comprises a substantially crystalline inorganic material such as a superparamagnetic material. In one embodiment, the inorganic core comprises a single crystal mixed spinel ferrite comprising iron in a first oxidation state and at least one metal in a second oxidation state, wherein the second oxidation state is different from the first oxidation state.

The invention discloses a preparation method for gold magnetic composite nanometer particles. Firstly, magnetic nanometer particles of Fe3O4 are prepared by using a chemical co-precipitation method, the surface of the magnetic particles are modified by a silane coupling agent, then with the modified nanometer particles of Fe3O4 as seeds and oil amine as a reduction agent, gold ions are reduced to metallic gold on the surface of the magnetic nanometer particles in an ultrasonic condition, then the nanometer particles are prepared. The nanometer particles have the advantages of good dispersion, strong magnetic response and having double bonds that can lead to polymerization reaction on the surface of the particles. The nanometer particles have the diameter of 30 to 50nm and saturation magnetization of 6.8 to 17.6 emu per gram, thus showing super paramagnetism. The nanometer particles not only have magnetic response function, but also can carry out polymerization reaction with a plurality of functional monomers, thus having wide application prospect in a plurality of fields, targeted drug control and release, hyperthermia, isolation of protein and enzyme, etc.