208 results about "Magnetic resonance imaging contrast medium" patented technology

A contrast agent for magnetic resonance imaging having a plurality of nanoparticles. Each of the nanoparticles has: a signal generating core having a diameter of up to 10 nm; at least one organic layer of at least one of a polymer, a monomer, and a surfactant; and a water soluble outer shell of at least one of a polymer, a monomer, and a ligand. The organic layer is adsorbed upon and substantially surrounds and stabilizes the signal generating core. The water soluble outer shell solubilizes and provides biocompatibility for each of the nanoparticles. The contrast agents provide enhanced relaxivity, high signal-to-noise ratios, and targeting abilities. In addition, the contrast agents possess resistance to agglomeration, controlled particle size, blood clearance rate, and biodistribution. Methods of making such contrast agents and nanoparticles are also disclosed.

Semiconductor nanoparticles are doped with paramagnetic ions to serve as dual-mode optical and magnetic resonance imaging (MRI) contrast agents. These nanoparticles can be constructed in smaller diameters than typical MRI agents. The dual-modality nature allows the particles to be used for in vivo imaging by MRI, and then followed by histology with optical imaging techniques.

Magnetic nanoparticles and a method for producing the same are disclosed. A carboxylated polysaccharide with various functions such as chelating and ion exchange is covalently bound on the surfaces of magnetic nanoparticles. The polysaccharide-bound magnetic nanoparticles are highly stable, well dispersed, and have many advantages of high adsorption capacity, fast adsorption rate and easy magnetically manipulation. Hence, the polysaccharide-bound magnetic nanoparticles are applied to adsorb many ionic substances, and further act as an adsorbent for wastewater treatment or biochemical separation, a carrier for drugs or gene site-directed delivery, and a magnetic resonance imaging (MRI) contrast agent.

The invention provides a magnetic resonance imaging contrast agent comprising a nucleic acid aptamer analogue and lipidosome of entrapping gadolinium, wherein the nucleic acid aptamer analogue is connected to the lipidosome of entrapping gadolinium by virtue of a chemical bond, and is selected from one or more of GBI-10, AS1411, A10, MUC1, sgc8, sgc3, sgd3, KHlCl, KDO5, S6, AGRO100, A30 and STRG2 modified by sulfydryl, amino or sites. The invention also provides a preparation method of the magnetic resonance imaging contrast agent, and application thereof in preparation of a tumor-targeted image detection preparation or a tumor-targeted treatment medicament. The magnetic resonance imaging contrast agent provided by the invention is stable in structure, the nucleic acid aptamer analogue is taken as a target head and oriented to a plurality of tumors, tumor cells can be discovered at an early stage, and the diagnosis and treatment effects are improved.

The present invention relates to an MRI contrast agent that includes zinc-containing water-soluble metal oxide nanoparticles and has an improved contrast effect. The zinc-containing water-soluble metal oxide nanoparticles are characterized by addition of zinc to a matrix comprising the metal oxide nanoparticles or by substitution of metal in the matrix, resulting in the improved contrast effect of MRI. In addition, the zinc-containing metal oxide nanoparticles of the present invention include the MRI contrast agent t having hybrid structures of “zinc-containing metal oxide nanoparticle—biologically/chemically active material” in which the nanoparticle is conjugated with a bioactive material such as proteins, antibodies, and chemical materials.

The invention relates to a preparation method for a nanometer graphene carrier used for an MRI contrast agent. According to the method, nanometer graphene oxide and hydrophilic high polymers are used as raw materials; the hydrophilic high polymers are grafted onto the surface of nanometer graphene oxide, and a contrast agent is loaded wherein. Compared to the prior art, the invention has the following advantages: by utilizing good hydrophilicity and biocompatibility of some hydrophilic high polymers and the characteristic that the system of nanometer graphene oxide and hydrophilic high polymers can enter into biological cells at a nanometer level, the contrast agent is enabled to have long in-vivo retention time, good histocompatibility and low cytotoxicity; the system shows a good application prospect in the aspect of MRI radiography.

The invention relates to a polysaccharide macromolecular paramagnetic metal complex and a synthesis method and an application thereof. Polysaccharide macromolecules are used as carriers, and a ligand compound, the side chains of which contain open-chain or annular polyamino polycarboxylic compounds, acts with paramagnetic metal ions to form the paramagnetic metal complex, wherein the paramagnetic metal ions are positive divalent or trivalent ions of metal elements, the atomic numbers of which are 21-29, 42 and 44 or 57-71. The polysaccharide macromolecular paramagnetic metal complex can be used as a magnetic resonance imaging contrast agent for lymphatic organs, lymphatic vessels, lymphatic systems and cardiovascular systems of people or other mammals.

The present invention provides binding moieties for fibrin, which have a variety of uses wherever detecting, isolating or localizing fibrin, and particularly fibrin as opposed to fibrinogen, is advantageous. Particularly disclosed are synthetic, isolated polypeptides capable of binding fibrin and recognizing the form of polymerized fibrin found in thrombi. Such polypeptides and disclosed derivatives are useful, e.g., as imaging agents for thrombi. Preferred embodiments useful as magnetic resonance imaging (MRI) contrast agents useful for detecting a thrombus in vivo are also disclosed.

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.

The invention relates to a dual-mode fluorescent/magnetic resonance imaging contrast agent based on mesoporous silica and a preparation method thereof. The preparation method comprises the following steps: dissolving CTAB, and adding NaOH; dropwise adding TEOS; stirring, aging, washing, drying and roasting; dispersing a product in a toluene solution, adding APTES, refluxing, washing, dispersing through water to obtain a solution a, adding a chelating agent in DMSO, dissolving, separately adding NHS and EDC, stirring, adding the solution a, adding a gadolinium salt, filtering, washing, and dispersing with water to obtain a solution b; adding fluorescent molecules containing carboxyl in another DMSO, separately adding NHS and EDC, stirring, adding the solution b, stirring, filtering, washing, drying to obtain the dual-mode fluorescent/magnetic resonance imaging contrast agent based on mesoporous silica. The difunctional contrast agent has the advantages of small particle size, stable performance, good biocompatibility and strong fluorescence and magnetic resonance signals.

The invention relates to a preparation method of a magnetic resonance imaging contrast agent, especially a preparation method of gadobutrol and gadoteridol. The invention takes cheap diethylenetriamine and aminodiethanol as starting raw materials, which then undergo simple substitution, cyclization, and alkylation and other reactions as well as the processes of desalination, centrifugation, purification and the like, so that gadobutrol or gadoteridol can be prepared. Specifically, when R1=R2=-CH2OH (ethylene oxide 2, 3-dimethanol), the method can be used for preparing gadobutrol; and when R1=H, R2=-CH3 (propylene oxide), the method can be used for preparing gadoteridol. Compared with prior art, the method in the invention has the advantages of widely available and cheap raw materials, low requirement for equipment, simple technical operation, high total yield of synthesis, and environment friendliness, thus being suitable for large scale industrial production.

The invention relates to a preparation method and application of a glucose-oxidase-modified mesoporous manganese dioxide composition, and effectively solves the problem of providing new drugs for treating tumor diseases by preparing a glucose-oxidase-modified mesoporous manganese dioxide composition so as to realize synergistic inhibition of tumor cell growth by sonodynamic therapy and starvationtherapy. The preparation method of the glucose-oxidase-modified mesoporous manganese dioxide composition comprises the following steps: modifying surfaces of mesoporous manganese dioxide particles with glucose oxidase through amide bond reaction; physically loading a small-molecular sound sensitizer in pore canals of the mesoporous manganese dioxide, thereby obtaining an internally loaded sensitizer; and then, performing covalent modification on the outer side of the internally loaded sensitizer with glucose-oxidase-modified pharmaceutical composition of mesoporous manganese dioxide nanoparticles. Particle sizes of the glucose-oxidase-modified pharmaceutical composition of the mesoporous manganese dioxide nanoparticles are 100-300 nm; and mass ratio of the glucose oxidase to the manganesedioxide is 1 to 5. The preparation method of the glucose-oxidase-modified mesoporous manganese dioxide composition disclosed by the invention is stable, reliable, and low in cost; and moreover, the glucose-oxidase-modified mesoporous manganese dioxide composition can be used as a magnetic resonance imaging contrast agent for performing real-time monitoring on tumors. Therefore, the glucose-oxidase-modified mesoporous manganese dioxide composition is an innovation in tumor treatment drugs.

The invention discloses a monolayer molybdenum disulfide-zinc ferrite nanocomposite material and a preparing method and application thereof, and relates to the field of novel nanocomposite materials. The material is composed of a molybdenum disulfide nanosheet and zinc ferrite nanoparticles, wherein the surface of the molybdenum disulfide nanosheet is evenly modified with the zinc ferrite nanoparticles, and the molybdenum disulfide nanosheet is of a layer-peeled structure. The zinc ferrite nanoparticles are assembled on the surface of the molybdenum disulfide nanosheet by means of the reaction of amino and carboxyl to form an amido bond. The method has the advantages that energy consumption is low, the cost is low, and the yield is high. The obtained composite material can serve as a magnetic resonance imaging contrast agent and a controllable drug carrier. A drug can reach and be gathered at the position of a focus under the guidance of a magnetic field, intelligent drug release and real-time curative effect evaluation can be achieved under the guidance of magnetic resonance imaging, and controllable adjustment of the magnetic resonance imaging effect and the drug loading capacity can be achieved by changing the relative content of molybdenum disulfide and zinc ferrite in the composite material.

Potential magnetic resonance imaging (MRI) contrast agents that are functionalized with crown compounds have been synthesized, and show target-specificity to the kidney and liver, along with excellent water solubility, high MR intensity enhancement efficiency, long resident lifetime, low dosage requirement, low cytotoxicity and prolonged excretion rate.

Magnetic resonance imaging contrast agents that include a plurality of gas vesicles configured to associate with a noble gas are provided. Also provided are magnetic resonance imaging methods that include administering to a subject a contrast agent that includes a plurality of gas vesicles, obtaining a magnetic resonance data of a target site of interest, and analyzing the data to produce a magnetic resonance image of the target site. The subject contrast agents and methods find use in magnetic resonance imaging applications.

The invention relates to a high-water-solubility nuclear magnetic resonance imaging contrast agent and a preparation method of the high-water-solubility nuclear magnetic resonance imaging contrast agent. The high-water-solubility nuclear magnetic resonance imaging contrast agent is gadolinium (III) complex which is based on 1, 4, 7, 10-tetraazacyclododecane-1, 4, 7-triacetic acid (DO3A) and modified by quaternary ammonium salt side chain. The nuclear magnetic resonance imaging contrast agent prepared by the gadolinium (III) complex is good in water solubility, stability and relaxation rate, and the relaxation rate of the nuclear magnetic resonance imaging contrast agent can be controllably adjusted by controlling the length of the side chain.

The invention relates to novel magnetic resonance imaging contrast agents and methods of detecting physiological signals or substances.

The invention relates to a nuclear magnetic resonance imaging contrast agent, in particular to a method of high-flexibility nuclear magnetic resonance imaging contrast agents based on high molecular nanometer particles prepared through fine emulsion polymenrization. The nuclear magnetic resonance imaging contrast agents are prepared from the composition of 1, 4, 7, 10-tetrazo heterocycle dodecane with long-chain alkane and gadolinium (Gd-DOTA for short) or the composition of diethylenetriamine pentaacetic acid and gadolinium (Gd-DTPA for short) for carrying out fine emulsion polymenrization preparation with high molecular monomers. The Gd-DOTA derivatives (Gd-DOTA derivatives for short) with the long-chain alkane and the Gd-DTPA derivatives (Gd- DTPA derivatives for short) with the long-chain alkane respectively have the structures as the first formula and the second formula, wherein the value of n is between 8 and 24.

A preparation method for magnetic resonance imaging contrast medium gadobutrol comprises the following steps: taking THF as a solvent, taking boron-protected 1, 4, 7, 10-tetraazacyclododecane (I) and 4, 4-dimehtyl-3, 5, 8-trioxabicyclo[5.1.0]octane (II) as raw materials, activating the raw materials by sodium hydride and performing ring-opening condensation to obtain an intermediate (III), performing mild hydrolysis to obtain an intermediate (IV), then successively reacting the intermediate (IV) with chloroacetic acid or bromoacetic acid and gadolinium oxide to prepare gadobutrol, performing desalting on the crude product, recrystallizing to obtain gadobutrol pure product. The preparation method comprises the beneficial effects of being mild in reaction condition, high in selectivity, relatively low in apparatus requirement, simple in technological operation, high in total yield, high in product purity, simple in purification, low in environment protection pressure, and relatively suitable for industrial production.

The invention discloses a method for manufacturing KMnF<3> nuclear magnetic resonance imaging contrast agents. The method includes accurately weighing corresponding raw materials including KF.2H<2>O and MnCl<2>.4H<2>O according to a molar ratio of 3:1; adding a proper quantity of potassium oleate into the raw materials; dissolving the raw materials and the potassium oleate into anhydrous ethanol; and uniformly stirring the anhydrous ethanol with the raw materials and the potassium oleate to obtain a mixture, then adding the mixture into a sealed reaction container, and heating the mixture at the temperature of 160 DEG C for 24 hours to obtain KMnF<3> spherical particles with particle sizes of 15nm. The KMnF<3> spherical particles are uniform in particle size distribution. The method has the advantages that nanometer crystals manufactured by the method are low in cell toxicity and high in biocompatibility after being modified, the contrast agents are high in relaxation efficiency (of 23.15mM.S<-1>) and low in r2/r1 ratio (of 3.23), and can be used for contrast-enhanced imaging for brains of mice as shown by primary animal nuclear magnetic resonance imaging experiments by the aid of colloidal solution manufactured by the KMnF<3> nuclear magnetic resonance imaging contrast agents; and the in-vivo retaining time of the KMnF<3> nuclear magnetic resonance imaging contrast agents is proper, and the KMnF<3> nuclear magnetic resonance imaging contrast agents can be used as novel medical nuclear magnetic resonance contrast agents.

The invention relates to a magnetic resonance image contrast agent which uses arabinogalactan as carrier, wherein its production comprises that: using ethylenediamine tetra acetic acid, diethylene triamine pentacetic acid N-butanimide active ester, ethylenediamine tetra acetic acid, or the anhydrides of diethylene triamine pentacetic, via one short connecting arm to react with amination arabinogalactan; forming amido bond to connect ethylenediamine tetra acetic acid or diethylene triamine pentacetic acid to the arabinogalactan, to match magnetic metal ion as manganese, iron or lanthanide rare-earth element, to obtain complex. The invention has significant liver selectivity and low cute toxin. And the inventive contrast agent can be used in magnetic resonance diagnosis, X-ray CT or Y-flash imaging diagnosis.

The invention discloses a carbon nanotube/chitosan/magnetic ferrite nanoparticle composite material. A preparation method of the material comprises the following steps of: coating chitosan polymer and magnetic ferrite nanoparticles on multi-wall carbon nanotubes from inside to outside in turn; modifying the surfaces of the carbon nanotubes by coating the chitosan; and depositing the magnetic ferrite nanoparticles on the carbon nanotubes in situ by a hydrothermal method. The material prepared by the method has higher saturation magnetization rate and T2 relaxation coefficient, and is a good magnetic resonance imaging contrast medium. In the invention, concentrated acid oxidation treatment is not required to be performed on the carbon nanotubes in advance, so that the structural integrity of the carbon nanotubes is protected; and the preparation method has the advantages of readily available raw materials, low cost and the like, is easy to operate and is suitable for industrial production.

The invention provides a paramagnetic metal complex and a synthetic method and application thereof. The paramagnetic metal complex is an arabinogalactan-modified 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacethyl paramagnetic metal complex. A magnetic resonance imaging contrast agent prepared from the paramagnetic metal complex has high stability, water solubility and relaxation rate and is targeted to liver and kidney, so that targeted imaging is realized, and the imaging contrast and definition are improved. The paramagnetic metal complex has a good effect on raising the early diagnosis levels of diseases of liver and kidney organs, is about 2 times the relaxation rate of dotarem, has very long targeted radiography imaging time, can be easily prepared into a solution with required concentration for intravenous injection, is suitable for sterilizing and disinfecting with a hot pressing method, can be selectively identified by an asialoglycoprotein receptor on a liver parenchyma surface, and has high selectivity on livers of human beings or other mammals.