453 results about "Iron oxide nanoparticles" patented technology

The invention provides for methods for producing water-soluble iron oxide nanoparticles comprising encapsulating the nanoparticles in phospholipids micelles. Also provided are methods for conjugating the inventive nanoparticles via functionalized phospholipids to a target molecule, such as an antibody. The invention further provides methods for using the nanoparticle-antibody conjugate of the invention as a contrast agent to image specific cells or proteins in a subject using fluorescent and magnetic imaging techniques.

Thermosensitive liposomes encapsulating paramagnetic iron oxide nanoparticles are used as a drug controlled release system. Paramagnetic iron oxide nanoparticles are used to generate heat by applying alternative magnetic field to cause leakage of drugs in the liposomes.

The present invention is a nanoparticle composition composed of an iron core with an iron oxide shell which is optionally coated with a micro-emulsion. The disclosed nanoparticle compositions are disclosed for use in hyperthermia treatment and imaging of cancer.

In a method of capturing carbon dioxide in a gas, carbon dioxide in a gas is adsorbed to the hybrid adsorbent prepared by mixing an adsorbent with iron oxide nanoparticles, microwaves are irradiated to the hybrid adsorbent and the carbon dioxide adsorbed to the hybrid adsorbent is desorbed from the hybrid adsorbent, and the carbon dioxide desorbed from the hybrid adsorbent is captured.

Disclosed is a process, which is used to eliminate heavy metal cations from the aqueous media, and provides a better solution for the existing problems of the separation systems like low efficiency and high costs. The heavy metal cations selected for this purpose are cadmium, lead and copper. The separation system consists of a two stage process: In the first stage, the iron oxide nanoparticles are suspended in an aqueous medium contaminated with the heavy metal cations. In the second stage, the solution is brought into contact with a ferromagnetic matrix (or a paramagnetic matrix) magnetized by the application of an outside magnetic field. The heavy metal cations are deposited on the matrix under the imposed magnetic field. This two-stage process makes it possible to separate the heavy metal cations from the aqueous medium. The wire matrices are upon the completion of separation washed away by water or air current.

The invention relates to a nano-sized composite silica brick and a production method thereof. The invention is characterized in that: raw materials and binder of the silica brick are as follows: silica granules and fine powders, waste silica brick granules, calcium carbonate nanoparticles, iron oxide nanoparticles, silicon dioxide nanoparticles, fluorite powders, lime and sulfite pulp wastes. The production method is based on the existing production process of the silica brick, and introduces compound nanopowders in optimal proportions in the production process of the silica brick after high-efficiency dispersion, to produce nano-sized composite silica bricks. With the addition of nanopowders, the performance of silica brick is significantly improved, and manifested as follows: 1) the particle size fraction is more reasonable, the accumulation is compact and the texture is uniform; 2) the slurry has good plasticity and moldability and the production efficiency is improved; 3) the burning temperature is decreased to 20 DEG C, thus realizing energy conservation and discharge reduction; 4) the tridymite is superior in crystallization conversion and has low content of quartz residues; 5) the number of closed pores is increased, the number of opened pores are reduced, the porosity is reduced, and the strength and refractoriness under load are increased; and 6) the final product has good appearance, smooth end surface and good bonding property, and the rate of qualified products is increased.

The present invention provides biomimetic contrast agents, dual functional contrast agents effective for therapeutic gene delivery and magnetic nanoparticles which comprise functionalized iron oxide nanoparticle cores, one of an inert gold layer, a layer of inert metal seeds or a silica layer and, optionally, one or both of an outer gold-silver nanoshell or a targeting ligand attached to the inert gold layer or the gold-silver nanoshell. Also provided are methods of in vivo magnetic resonance imaging, of treating primary or metastatic cancers or of ablating atherosclerotic plaque using the contrast agents and magnetic particles. In addition, kits comprising the biomimetic contrast agents, dual contrast agents and magnetic nanoparticles.

Iron oxide nano contrast agents for Magnetic Resonance Imaging which have superior T₂ contrast effect, and also can be used as a storage or a carrier for drugs and so on, are disclosed. The iron oxide nano contrast agents can be prepared by the steps of: coating surfaces of hydrophobic FeO nanoparticles with a coating material selected from the group consisting of polyethylene glycol-phospholipid conjugate, dextran, chitosan, dimercaptosuccinic acid and mixtures thereof in an organic solvent to form hydrophilic FeO nanoparticles having hydrophilic surfaces and dispersibility in water; dispersing the hydrophilic FeO nanoparticles in water to oxidize FeO; and exposing the oxidized hydrophilic FeO nanoparticles to an acidic buffer to dissolve and remove interior unoxidized FeO portions, and thereby to form Fe₃O₄ nanoparticles having an interior space.

The invention belongs to the technical field of lithium ion battery materials, and specifically relates to a porous graphene supported carbon coated iron oxide nanoparticle composite material and a preparation method thereof. The porous graphene supported carbon coated iron oxide nanoparticle composite material is prepared from the following steps: (1) directly preparing graphene oxide with graphite ore as a raw material by using a closed oxidation method; (2) preparing a ferric salt aqueous solution, wherein the specific steps are as follows: weighing and dissolving cetyl trimethyl ammonium bromide in water to obtain a clear cetyl trimethyl ammonium bromide solution, adding a ferric salt, stirring until the ferric salt is completely dissolved, and adding an ammonia solution to prepare the ferric salt aqueous solution; and (3) stirring and ultrasonic mixing the graphene oxide solution with the ferric salt aqueous solution, placing the mixture in a water bath kettle, reacting at 80-100 DEG C for 0.5-5h, stewing at a room temperature, removing clear liquid, freeze drying a head product, and carrying out heat treatment on the head product in an inert atmosphere to obtain the porous graphene supported carbon coated iron oxide nanoparticle composite material.

The invention discloses a preparation method of RGD-modified ultra-small magnetic iron oxide nanoparticles. The preparation method comprises the following steps: preparing ultra-small magnetic iron oxide nanoparticles by taking ferric acetylacetonate as a reaction raw material and a precursor, taking oleylamine as a surfactant and a reducing agent and taking dibenzyl ether as a solvent; replacing oleylamine molecules wrapped on the surfaces of the nanoparticles by utilizing dopamine-modified HOOC-PEG-COOH to realize PEG-modification of the surfaces of the nanoparticles; and finally, chemically coupling RGD cyclic peptide by virtue of free carboxyl at the tail end of the PEG to obtain the RGD-modified ultra-small magnetic iron oxide nanoparticles. The method of synthesizing the ultra-small magnetic iron oxide nanoparticles has the characteristics of a simple process, a high raw material conversion ratio, strong repeatability and the like. The synthesized magnetic iron oxide nanoparticles have the characteristics of a regular morphology, an ultra-small dimension, good stability, good monodispersity, high biocompatibility, and tumor specific targeting, and the like, and can be used as a T1-weighted imaging high-performance magnetic resonance imaging contrast agent with a tumor active targeting function.

The invention provides a magnetic iron oxide-silicon dioxide-phenolic resin polymer composite nanometer material with a core-shell structure, a preparation method and application of the composite nanometer material. The material has a regular spherical morphology; an inner core is magnetic iron oxide nano particles; an inner shell layer is silicon dioxide; an outer shell layer is a phenolic resin polymer; the thicknesses of the inner shell layer and the outer shell layer can be modulated; the outer shell layer can be transformed into carbon after high-temperature treatment in nitrogen; and the overall morphology and the structure of the material are kept invariable. The material is prepared by the following steps: introducing magnetic iron oxide nano particles into a mixed solution of ethyl alcohol/deionized water/ammonium hydroxide; and adding a silicon source and a carbon source to carry out hydrolysis and polymerization reaction. The magnetic iron oxide-silicon dioxide-phenolic resin polymer composite nanometer material has the effects and advantages that the provided core-shell material is good in stability and simple in preparation process, and can be used for adsorbing and separating a nano noble-metal catalyst carrier.

Contrast agents incorporating super-paramagnetic iron-oxide (SPIO) nanoparticles have shown promise as a means to visualize labeled cells using MRI. Labeled cells cause significant signal dephasing due to the magnetic field inhomogeneity induced in water molecules near the cell. With the resulting signal void as the means for detection, the particles are behaving as a negative contrast agent, which can suffer from partial-volume effects. Disclosed is a new method for imaging labeled cells with positive contrast. Spectrally-selective RF pulses are used to excite and refocus the off-resonance water surrounding the labeled cells so that only the fluid and tissue immediately adjacent to the labeled cells are visible in the image. Phantom, in vitro, and in vivo experiments show the feasibility of the new method. A significant linear correlation (r=0.87, p<0.005) between the estimated number of cells and the signal has been observed.

The invention belongs to the technical field of transition metal oxide-carbon aerogel, and particularly discloses an iron oxide nano-particle/graphene-polyimide-based carbon aerogel composite material and a preparation method thereof. The composite material is formed by evenly loading iron oxide nano-particles on graphene-polyimide-based carbon aerogel. The method comprises the following preparation step: carrying out in-situ growth of the iron oxide nano-particles on the graphene-polyimide-based carbon aerogel activated by potassium hydroxide through a one-step solvothermal method. The method disclosed by the invention is free of use of a toxic reagent, namely formaldehyde; and the prepared iron oxide nano-particle/graphene-polyimide-based carbon aerogel composite material has the advantages of small iron oxide nano-particles, uniform distribution, high porosity, high specific surface area, high conductivity, stable physical and chemical properties and the like, and can be used for preparing a high-sensitivity biosensor, a high-performance adsorption material and ideal electrode materials for new energy devices of a super capacitor, a lithium-ion battery and the like.

A preparation method of silica-coated iron oxide nano-core-shell structural material includes: dissolving molysite, acetic acid and polyvinylpyrrolidone in ethanol, and mixing well; moving the solution into a polytetrafluoroethylene reactor, allowing the solution to react at the heating temperature of 160-220 DEG C for 3-48 hours and under the mixing speed of 10-100rpm, and obtaining 0.1-8g/L iron oxide nanoparticle suspension; and adding the ethanol and deionized water into the suspension, allowing the volume ratio of the ethanol to water in the suspension system to be 0.5-10/1, adjusting pH value to be 7-12, allowing the mass ratio of tetraethoxysilane to iron oxide nanoparticles to be 1:1-40, slowly adding the tetraethoxysilane under mixing, allowing the mixture to react for 12-70 hours, performing filtering and drying, and calcining at 400-600 DEG C to obtain the silica-coated iron oxide nano-core-shell structural material, wherein the molar concentration of the molysite in solution is 0.01-0.1mol/L, the volume ratio of the acetic acid to the ethanol is 0.002-1:1, and the mass concentration of the polyvinylpyrrolidone in the solution is 1.5-20g/L. The preparation method has the advantages that synthetic process is simple, cost is low, operation is simple, and amplification and synthesis are easy.

The invention discloses a nanometer iron oxide/carbon sphere compound catalyst and a preparation method and an application thereof, which belong to the technical field of catalysts. Iron oxide nano particles are uniformly loaded on the surfaces of carbon spheres. The preparation method comprises the following steps of modifying the surfaces of the carbon spheres by performing a Fenton reaction, i.e., under the strong oxidizing property in the coexistence of hydrogen peroxide and ferrous ions; and uniformly loading iron oxide on the surfaces of the carbon spheres to obtain the nanometer iron oxide/carbon sphere compound catalyst. Due to the adoption of the method, the problems of severe aggregation and the like of a nanometer iron oxide catalyst and the like are solved, and the obtained nanometer iron oxide/carbon sphere compound catalyst is taken as an efficient combustion catalyst for solid propellants, a catalyst for photo-degradation organic matters, and a catalyst for petroleum cracking.

Aqueous and substantially crystalline iron oxide nanoparticle dispersions and processes for making them are disclosed. The nanoparticle size and size distribution width are advantageous for use in a fuel additive for catalytic reduction of soot combustion in diesel particulate filters. Nanoparticles of the aqueous colloid are transferred to a substantially non-polar liquid comprising a carboxylic acid and one or more low-polarity solvents. The transfer is achieved by mixing the aqueous and substantially non-polar materials, forming an emulsion, followed by a phase separation into a substantially metal-free remnant polar phase and a substantially non-polar organic colloid phase. A method for rapid and substantially complete transfer of non-agglomerated nanoparticles to the low polarity phase in the presence of an organic amine, and a rapid phase separation of the substantially non-polar colloid from a remnant aqueous phase, are provided.

The present disclosure includes a method for preparing an aqueous dispersion of γ-Fe₂O₃ nanoparticles. The method includes grinding an iron (II) hydrated salt, an iron (III) hydrated salt, an inorganic salt, and alkali hydroxide in a grinding or milling machine. The inorganic salt may be a salt matrix that prevents growth and aggregation of the synthesized nanoparticles. The aqueous dispersion of γ-Fe₂O₃ nanoparticles may optionally be hydrothermally treated to become an aqueous dispersion of α-Fe₂O₃ nanoparticles. Also disclosed is a method for preparing an mixture of α-Fe₂O₃ nanoparticles and γ-Fe₂O₃ nanoparticles, in which at least an iron (III) hydrated salt, an inorganic salt, and alkali hydroxide are ground in a grinding or milling machine. Uses for the nanoparticles include: a magnetic resonance image contrast agent, a color print ink, an artificial tanning pigment, a photocatalyst for degradation of organic dye, a red pigment, an adsorbent for waste water treatment, a catalyst support, and a catalyst.

The invention relates to a preparation method of a graphene-supported iron oxide nanoparticle composite wave-absorbing agent, comprising: (1) preparing composite precursor powder by a spray process, to be specific, using iron nitrate nonahydrate as an iron source, anhydrous glucose as a carbon source and sodium chloride as a template with a molar ratio of Fe, C and NaCl being (0.75-2):30:100, dissolving the iron source, the carbon source and the sodium chloride in deionized water, magnetically stirring to obtain aa homogenous mixed solution, and subjecting the solution mixed well to spray drying to obtain precursor powder; reducing the composite precursor powder by calcining; oxidizing the composite precursor powder by calcining; removing the NaCl template. The graphene-supported iron oxide nanoparticle composite prepared by using the preparation method is applied to electromagnetic wave absorption.

The present invention relates to gold nanocages containing magnetic nanoparticles and a preparation method thereof. More specifically, relates to hollow-type gold nanocage particles, which contain iron oxide nanoparticles having a magnetic property and have an optical property of strongly absorbing or scattering light in the near-infrared (NIR) region, as well as a preparation method thereof. Due to their optical property and magnetic property, the magnetic nanoparticle-containing gold nanocages can be used in various applications, including analysis in a turbid medium with light, cancer therapy or biomolecular manipulation using light, contrast agents for magnetic resonance imaging, magnetic hyperthermia treatment and drug delivery guide, etc.

The present invention relates to a method of preparing biocompatible iron oxide nanoparticles by coating iron oxide nanoparticles having improved magnetism via annealing treatment using salt particles with a hydrophilic material and to a magnetic resonance imaging (MRI) contrast agent including the iron oxide nanoparticles prepared thereby. Among hydrophilic materials, carboxymethyl dextran (CM-dextran) is the most efficient in terms of stabilizing the annealed iron oxide nanoparticles and exhibiting contrast effects.

The present invention relates to a process for preparing water-soluble and dispersed iron oxide (Fe₃O₄) nanoparticles and application thereof, characterized in which two-stage additions of protective agent and chemical co-precipitation are employed in the process. In the first stage, Fe₃O₄ nanoparticles are obtained using absorbent-reactant coexistence technology. In the second stage, proper amount of adherent is added to cover the nanoparticle surface entirely. The resulting water-soluble and dispersed Fe₃O₄ nanoparticles can easily bind with thiols or biomolecules, such as nucleic acid and peptide. The Fe₃O₄ nanoparticles of the present invention may be used as magnetic resonance imaging contrast agent and used in magnetic guiding related biomolecular technologies for clinical testing, diagnosis and treatment.

An embodiment in accordance with the present invention provides a thermo-chemoembolization formulation and method for enhanced interventional image-guided therapy for cancer. The T-C formulation includes magnetic iron oxide nano-particles (MIONs) that heat when exposed to an alternating magnetic field (AMF), a liquid tumorphilic drug carrier that enhances tumor retention of the T-C formulation, and a chemotherapeutic or radiotherapeutic agent. The T-C formulation enhances delivery of heat and chemo- or radio-therapeutic agents with hyperthermia produced by magnetic nanoparticles to improve therapeutic outcomes. The magnetic nanoparticles and tumorphilic drug carrier also allow for multimodal image-guided monitoring of treatment and patient follow-up. The method for enhanced interventional image-guided therapy for cancer includes using an AMF to heat the T-C formulation and activate the thermotherapy.