121 results about "Superparamagnetic nanoparticles" patented technology

This invention relates generally to NMR systems for in vivo detection of analytes. More particularly, in certain embodiments, the invention relates to systems in which superparamagnetic nanoparticles are exposed to a magnetic field and radio frequency (RF) excitation at or near the Larmor frequency, such that the aggregation and/or disaggregation of the nanoparticles caused by the presence and/or concentration of a given analyte in a biological fluid is detected in vivo from a monitored RF echo response.

Paramagnetic or superparamagnetic nanoparticle-ligand conjugates that include a recognition ligand that interacts with a component on the surface of a prostate cancer cell. Nanoparticle-ligand conjugates of the invention may be used for magnetic resonance imaging of prostate cancer, or for treatment of tumors by targeted thermal ablation.

A biomolecular sensor system includes an array of magnetoresistive nanosensors designed for sensing biomolecule-conjugated superparamagnetic nanoparticles. Materials and geometry of each sensor element are designed for optimized sensitivity. The system includes magnetic field generators to apply forces to superparamagnetic nanoparticles for 1) nanoparticle manipulation, 2) sensor magnetic biasing, 3) magnetic pull-off measurement for differentiation against non-specific association, and 4) removal of all particles from the sensor array surface.

The injectable formulation for treatment by hyperthermia comprises a liquid carrier and heat-generating superparamagnetic iron oxide nanoparticles having a mean diameter not greater than 20 nm. Said injectable formulation is able to form in-situ a hyperthermic solid or semi-solid implant upon contact with a body fluid or tissue. Said hyperthermic solid or semi-solid implant may be useful for treating a tumor or a degenerative disc disease by hyperthermia.

The current invention is a novel superparamagnetic site-targeting nanoparticle comprising superparamagnetic nanoparticles encapsulated with a smart polymer. The superparamagnetic site-targeting nanoparticle comprises a functionalized superparamagnetic core that is conjugated with a therapeutic agent and then encapsulated with a smart polymer. The smart polymer can be any polymer that exhibits a reversible conformational or physio-chemical change in response to an external stimulus or stimuli.

A high-resolution sensor of magnetic field sensor system and materials for use in such a system are described. The sensor systems measure a magnetic field using inorganic and/or organic magneto-optically active materials, e.g. polymer material and have an interferometer based on Faraday rotation. The polymer material is preferably in the form of a film. The polymer material has an optical property that is sensitive to the magnetic field, e.g. the Faraday rotation effect. The present invention also provides a sensor head structure comprising the above polymer material. The sensor head may be designed for use with an optical fiber or with mirrors. In particular the present invention provides a fiber Sagnac interferometer to measure the rotation of polarized plane of light. The present invention provides a fiber or mirror based Sagnac interferometer with passive phase bias applied to magnetic field sensing. This invention has the following three major aspects each being an embodiment of the present invention: 1. Sensing material: a conjugate polymer such as polythiophene and/or a polymer containing superparamagnetic nanoparticles that exhibits a giant Faraday rotation. 2. Magnetic field probe that incorporates the above polymer or polymer/nanoparticle composite, e.g. in the form of a film. 3. Sensor: The sensor combines an optical fiber-based Sagnac interferometer and the above magnetic field probe.

The invention provides a superparamagnetic nanoparticle Fe3O4@SiO2@PSA modified by the PSA and a preparing method and application of the superparamagnetic nanoparticle Fe3O4@SiO2@PSA modified by the PSA. According to the superparamagnetic nanoparticle Fe3O4@SiO2@PSA modified by the PSA and the preparing method and application of the superparamagnetic nanoparticle Fe3O4@SiO2@PSA modified by the PSA, silylanization is conducted on the surface of superparamagnetic nanoparticle Fe3O4, a silylating reagent with a PSA structure is bonded, and thus a PSA group is introduced. The superparamagnetic nanoparticle Fe3O4@SiO2@PSA modified by the PSA and the preparing method of the superparamagnetic nanoparticle Fe3O4@SiO2@PSA modified by the PSA can be applied to the magnetic solid-phase extraction (M-SPE) field, and the superparamagnetic nanoparticle Fe3O4@SiO2@PSA modified by the PSA can serve as an adsorbent which is frequently used for magnetic solid-phase extraction, be applied to various pesticides such as carbamic acid ester, the organophosphorus pesticide and the herbicide and be used for absorption and extraction of target objects such as sulfonamides, organic acid and saccharides; meanwhile, the functional group of the PSA is a good binary ligand, in this way, the PSA is a good chelation material, can be used for extraction of metal ions and has high practical value and broad application prospect in the aspect of analytical investigation.

Disclosed is a technique for classifying tissue based on image data. A plurality of tissue parameters are extracted from image data (e.g., magnetic resonance image data) to be classified. The parameters are preprocessed, and the tissue is classified using a classification algorithm and the preprocessed parameters. In one embodiment, the parameters are preprocessed by discretization of the parameters. The classification algorithm may use a decision model for the classification of the tissue, and the decision model may be generated by performing a machine learning algorithm using preprocessed tissue parameters in a training set of data. In one embodiment, the machine learning algorithm generates a Bayesian network. The image data used may be magnetic resonance image data that was obtained before and after the intravenous administration of lymphotropic superparamagnetic nanoparticles.

The invention relates to a method for preparing a superparamagnetic nanoparticle photocatalyst with a Fe3O4-PAMAM-TiO2 core-shell structure by using polyamide-amine (PAMAM) dendrimer as a template and an isolation layer in a low-temperature aqueous solution. The method is characterized by comprising the following steps: firstly, with the PAMAM dendrimer as the template, preparing a superparamagnetic Fe3O4-PAMAM nanoparticle colloidal solution by using a co-precipitation method; then adding the PAMAM dendrimer with different terminal groups and coating Fe3O4-PAMAM nanoparticles so as to form a dendrimer isolation layer; finally, dropwise adding a TiCl4 absolute ethanol solution, and carrying out normal pressure reaction and hydrothermal reaction so as to obtain the nanoparticles with the Fe3O4-PAMAM-TiO2 core-shell structure and a complete TiO2 shell layer; and carrying out washing and redispersion so as to obtain the nanoparticle photocatalyst with the Fe3O4-PAMAM-TiO2 core-shell structure.

The invention belongs to the technical field of biomedical polymer material and nanobiomaterial, particularly relates to a magnetic nano-carrier with targeted hydrophobic drug delivery to tumor and a preparation method thereof. The magnetic nano-carrier is formed by encapsulating superparamagnetic nano-particles with amphiphilic segmented copolymer methoxy polye thylene glycol-poly(lactide- glycolide) (MePEG-PLGA) micelles. First, a large amount of MePEG-PLGA with good dispersion is synthesized by the improved solution polymerization process, and then the MePEG-PLGA is used as raw materials to encapsulate Fe3O4 nano-particles by the solvent evaporation process to obtain a magnetic nano drug carrier. The carrier is expected to solve the solubility problem of insoluble drugs, achieves slow release of drugs, and achieves the passive-targeting of the drugs by the EPR effect of tumor; Fe3O4 nano-particles are used in the active-targeting of the drugs to reduce the dosage and the side effect and improve the treatment efficiency; besides, the carrier can be used in the magnetic resonance imaging (MRI) of tumor.

The invention relates to a preparation method of thermo-magnetic dual responsive mesoporous silicon microspheres. The preparation method comprises the following steps: 1) synthesis of magnetic nanoparticles; 2) preparation of Fe3O4@SiO2 nanoparticles; 3) synthesis of magnetic responsive mesoporous silicon microspheres [M-MSN-CTAB (Magnetic-Mesoporous Silicon Nanoparticle-Cetyltrimethyl Ammonium Bromide)]; 4) modification of M-MSN-CATB; 5) preparation of the thermo-magnetic dual responsive mesoporous silicon microspheres [M-MSN-PNIPAAm (Poly N-Isopropyl Acryl Amide)]. The preparation method provided by the invention is reasonable in design method and simple and feasible in operation, and can be used for successfully preparing novel thermo-magnetic dual responsive M-MSN by taking superparamagnetic Fe3O4 nanoparticles as a core, mesoporous silicon as a middle interlayer and a temperature sensitive copolymer as a shell. The M-MSN-PNIPAAm has the characteristics of superparamagnetism, high specific surface area and high pore volume of mesoporous silicon and temperature response. The M-MSN-PNIPAAm can be used as a carrier of medicines to prevent medicines and active components from being damaged, and purpose of targeted delivery and controlled release is realized.

The invention discloses an exosome preparation derived from a stem cell. The exosome preparation is an exosome secreted by a Fe3O4 superparamagnetic nanoparticle stimulating the stem cell. The invention further provides the application of the exosome preparation in preparing a pharmaceutic preparation for promoting mesenchymal stem cell osteogenic differentiation and the application of the exosomepreparation in preparing a biological agent for treating orthopedic disorders or bone repair materials. In consideration of the complicated pathophysiologic process of osteonecrosis and bone defects,the exosome preparation prepared by the exosome secreted by the Fe3O4 superparamagnetic nanoparticle stimulating the stem cell is adopted, intramuscular administration can be adopted at local bone defect parts, or local filling is performed after the exosome preparation is mixed with absorbable gel, the exosome preparation directly reaches the focus, the osteogenic activity of the mesenchymal stem cell is motivated, the deposition of osteoblasts is promoted, and the repair of the osteonecrosis or bone defects is promoted.

The invention provides a supported catalyst with the structural formula I shown in the specification. In the formula I, a carrier is superparamagnetic nanoparticles or superparamagnetic nanoparticles wrapped by silicon dioxide; M is metal ions, X<-> is inorganic or organic negative ions; R<1> is C1-C6 alkyl, halogen substituted C1-C6 alkyl, C6-C12 aryl, halogen or C1-C6 alkyl substituted C6-C12 aryl, halogen or C1-C4 alkoxy; R<2> and R<3> are respectively C1-C6 alkyl or C6-C12 aryl, or R<2> and R<3> are connected with each other to form -(CH2)3- or -(CH2)4-; a linker is a connector. The invention further discloses a preparation method of the supported catalyst. The supported catalyst can be used as a chiral catalyst for asymmetric epoxidation reaction.

The invention provides a method for preparing high-magnetization chitosan nanospheres. according to the invention, an improved ultrasonic emulsification pre-crosslinking technique is adopted, namely, a chitosan solution in which superparamagnetic nanoparticles are dispersed is taken as a water phase, and liquid paraffin is taken as an oil phase, a high-magnetization and particle-size-controlled chitosan nanosphere is obtained through adjusting the composition of the oil and water phases and carrying out mixing, ultrasonic dispersion and ultrasonic pre-crosslinking,. The preparation method provided by the invention is simple, high in efficiency and low in cost; the highest saturation magnetization of the obtained chitosan nanosphere can be more than 45 emu/g; and the method has great application potentials in the fields of biological medicines, enzyme engineering and magnetic separation.

The invention discloses a method for preparing an ordered magnetic nanoparticle composite film with super-high density, which comprises the steps of: at first, preparing FePt/CoPt superparamagnetic nanoparticle; self-assembling a FePt/CoPt superparamagnetic nanoparticle-containing nonmagnetic substrate and using an atomic layer deposition technique to grow an inorganic nonmagnetic matrix film protective layer of 10-30 nanometers on the surface of the substrate containing a single layer of FePt/CoPt nanoparticle lattice; putting the deposited substrate in a tubular diffusion furnace for annealing for 30 to 90 minutes at high temperature from 600 to 750 DEG C in a reducing atmosphere of 90-97% of Ar and 10-3% of H2 to result in the composite film of FePt/CoPt ferromagnetic nanoparticles and oxides. The method can obtain the ordered FePt/CoPt nanoparticle composite film with L10 phase, good magnetic property and the magnetic coercive field up to Hc=5.9kOe.

The invention is directed to hydrophilic and hydrophobic superparamagnetic nanoparticles and their use as contrast agents for NMR including agents that distinguish oil and water in NMR logging of geological formations containing oil or water. Methods of making these SPIONs are also described.