138results about How to "High relaxation rate" patented technology

Polymerized liposome particles which are linked to a targeting agent and may also be linked to a contrast enhancement agent and / or linked to or encapsulating a treatment agent. The targeting imaging enhancement polymerized liposome particles interact with biological targets holding the image enhancement agent to specific sites providing in vitro and in vivo study by magnetic resonance, radioactive, x-ray or optical imaging of the expression of molecules in cells and tissues during disease and pathology. Targeting polymerized liposomes may be linked to or encapsulate a treatment agent, such as, proteins, drugs or hormones for directed delivery to specific biological sites for treatment.

Disclosed herein are nanostructures comprising a polymeric framework comprising at least five geminal bisphosphonate groups, wherein the geminal bisphosphonate groups independently of each other are incorporated as —R3R4C(P═O(OR1)(OR2))2, wherein R1 and R2 are independently selected from the group consisting of a negative charge, H, alkyl and aryl, and wherein at least one of R3 and R4 is a group connected to the polymeric framework with the proviso that when only one of R3 and R4 is such a connected group, the other of R3 and R4 is either a group being able to connect to the polymeric framework, or the residue of such a group, or selected from the group consisting of H, OH, OR5 and R5, wherein R5 is a lower alkyl. The polymeric framework may comprise manganese ions. Disclosed are also methods for producing such manganese containing nanostructures, compositions comprising such manganese containing nanostructures and use of such manganese containing nanostructures, i.a. as MRI contrasting agents.

The invention relates to a preparation method of HPEI (hyperbranched polyethyleneimine)-encapsulated ferroferric oxide magnetic nano particles, comprising the steps of: adding Fe source to ultrapure water, then adding NH3.H2O, stirring in air, adding HPEI, and reacting at 134-140 DEG C for 3h, wherein the mass ratio of Fe source to HPEI is 1-5 :1; cooling, and carrying out washing and magnetic separation on precipitate to obtain HPEI-encapsulated ferroferric oxide nano particles Fe3O4 / HPEI; and then carrying out different surface modification on the Fe3O4 / HPEI nano particles, such as polyethylene glycolation (PEGlation), acetylation and carboxylation, so as to increase biocompatibility of the nano particles to be used for MRI (magnetic resonance imaging) diagnosis. The process is simple, the reaction conditions are mild and operation and separation are easy; and the prepared iron oxide magnetic nano particles have excellent biocompatibility and T2 relaxation effect, and have potential application value in the field of MRI imaging diagnosis.

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 invention relates to a preparation method of ferric oxide nanoparticle supported sodium alginate nanogel. The preparation method comprises steps as follows: (1), PEI (polyethylenimine) coated Fe3O4 nano-particles (Fe3O4-PEI) are synthesized with a hydrothermal method; (2), an aqueous solution of sodium alginate is firstly activated by EDC (carbodiimide) and has a double emulsion reaction to form a W / O / W polymer emulsion; (3), Fe3O4-PEI in the step (1) is taken as a crosslinking agent and added into the polymer emulsion in the step (2) to have a crosslinking reaction, and the ferric oxide nanoparticle supported sodium alginate nanogel is obtained after an organic solvent and a surface active agent are removed. The method is very simple, and operation and separation are easy; meanwhile, sources of raw materials are extensive; the prepared sodium alginate nanogel has a smaller grain diameter, is uniformly distributed, high in relaxation rate and low in cost, has a remarkable radiography effect, simultaneously has excellent water solubility, gel stability, biocompatibility and blood compatibility, doesn't have a harmful effect on a living body, and has potential application value in the magnetic resonance imaging diagnosis field.

The invention relates to a rare earth-based nanoparticle magnetic resonance contrast agent and a preparation method thereof. The rare earth-based nanoparticle magnetic resonance contrast agent are rare earth-based inorganic nanoparticles having the surface coated with a hydrophilic ligand, firstly rare earth-based nanoparticles are obtained through a high-temperature oil phase reaction, and then the surface is coated with hydrophilic molecules to obtain the rare earth-based nanoparticle magnetic resonance contrast agent. Compared with a conventional clinical contrast agent, the magnetic resonance contrast agent has the relaxation rate greatly improved, is good in imaging effect, low in required injection dose, and relatively long in time staying in a body. In addition, a rigid structure of the inorganic nanoparticles can effectively reduce the free possibility of gadolinium ions. The rare earth-based nanoparticle magnetic resonance contrast agent has the advantages of simple preparation method, good repeatability and stable property, and easily realizes clinical commercial applications.

The invention synthesizes a type of liver targeted, biodegradable high molecular MRI contrast medium with alpha,beta- poly [(2-aminoethyl) - L-asparagine] as fundamental chain, galactose as target gene, diethylenetriamine pentaacetic acid or L-tyrosine methyl ester derivatives as Gd3+ ligand. The contrast agent is less toxic, biocompatible, and has good relaxation rate than low molecular business contrast medium. Animal experiments showed that in liver organizations its enhancing effect is three times better than commercial and low molecular contrast medium (gadolinium sprayed acid cyelophosphate); the residence time in liver is more than 24 hours, which is 18 hours longer than low molecular business contrast medium. The feature is that Zeta potential for the contrast medium is negative and less than -10mV. We can achieve the MRI visible, the liver targeted, core-shell nanogene vector system with it as a gene vector system shell structure.

The invention discloses a method for preparing a supermolecule capsule with multiple drug release stimulation and MRI radiography ability. A ferroferric oxide microcapsule is prepared as a novel multifunctional magnetic resonance noise and drug therapy medicament through a layer-by-layer self-assembly technology. Through the host-guest interaction and the Coulomb interaction of different supramolecular polymers, the medicine molecule is controllably released through the non-invasive ultraviolet radiation distributed azobenzene isomerism and the acid response Schiff base. Additionally the magnetic-targeted MRI contrast agent is obtained by encapsulating the superparamagnetic ferroferric oxide granule. The r2 relaxation rate of the microcapsule is increased by 37% to reach 125.71 mM-1S-1 compared with that of the neutral condition (92.02mM-1S-1) through the stimulation of subacidity (pH=5.6).

The invention discloses a degradable dendritic macromolecule magnetic resonance contrast agent and a preparation method thereof. The degradable dendritic macromolecule magnetic resonance contrast agent is characterized in that a degradable dendritic macromolecule is used as a skeleton and micromolecular gadolinium chelates are connected to the degradable dendritic macromolecule so that the degradable dendritic macromolecule magnetic resonance contrast agent is formed. The degradable dendritic macromolecule magnetic resonance contrast agent has a relaxation rate of 17.4mM<-1>.s<-1> obviously higher than a relaxation rate of the common contrast agent, has a better MRI contrast effect, can be enriched in tumor tissue by enhanced permeation and retention effects of the degradable dendritic macromolecule magnetic resonance contrast agent, and improves MRI sensitivity and an early diagnosis level of cancers. The degradable dendritic macromolecule magnetic resonance contrast agent can be hydrolyzed by internal esterase catalysis and then is gradually discharged out of a human body so that the toxicity accumulation of gadolinium in a human body is avoided. The preparation method has simple processes, can be controlled easily and is suitable for industrial large-scale production.

The invention relates to a nanometer magnetic resonance contrast material, a nanometer magnetic resonance contrast agent and a preparation method of the nanometer magnetic resonance contrast agent. The nanometer magnetic resonance contrast material comprises a core having the chemical formula of A3x[GdyFeIII1-y](4-x)[FeII(CN)6]3.nH2O, and a casing which is composed of auxiliary materials and coats the core. In the chemical formula, A represents Li<+>, Na<+>, K<+> or NH4<+>, x is greater than 0 and less than or equal to 1, y is in a range of 0-1, and n is in a range of 1-16. The nanometer magnetic resonance contrast agent prepared from the nanometer magnetic resonance contrast material has stable properties, is decomposed and ionized difficultly, has low toxicity and is suitable for injection and oral administration.

The invention provides a preparation method of a targeted superparamagnetic nano-probe. The method includes the steps of: 1. preparing ferroferric oxide nano-particles with a particle size of 10-20nm in an oil phase by high temperature thermal decomposition; 2. synthesizing an amphiphilic polymer; 3. conducting aqueous phase transformation of the ferroferric oxide nano-particles obtained by step 1 through the amphiphilic polymer obtained by step 2 so as to obtain water-soluble superparamagnetic nano-particles; and 4. under the coupling effect of EDC / NHS, subjecting the water-soluble superparamagnetic nano-particles obtained by step 3 to covalent coupling with a target molecule, thus obtaining the targeted superparamagnetic nano-probe. The invention also provides an application method of the probe. Under the action of a separation column and an applied magnetic field, the probe can specifically and effectively capture and separate target cells. Compared with the prior art, the probe prepared by the method provided by the invention has the advantages of uniform particle size, high T2 relaxation rate, good stability, high pH value, high salt tolerance, and good target cell separation effect.

The invention relates to a multi-mode targeted probe for early hepatic fibrosis diagnosis and a preparation method thereof. The multi-mode targeted probe for the early hepatic fibrosis diagnosis is characterized by comprising a vector, and the vector is connected with a fluorescence group and a magnetic resonance imaging group and can be connected with a targeted compound group, which can be combined with a receptor on the surface of a hepatic stellate cell in hepatic fibrosis / cirrhosis, through a bridging group. The preparation method comprises the steps of: connecting the targeted compound group, which can be combined with the receptor on the surface of the hepatic stellate cell in the hepatic fibrosis / cirrhosis, with the bridging group, and sequentially connecting the targeted compoundgroup, the fluorescence group and the magnetic resonance imaging group on the vector. The targeted probe has higher sensitivity when being used for diagnosing and evaluating the fibrosis diagnosis.

The invention relates to a rare earth nanoparticle with multimodal imaging functions of magnetic resonance imaging (MRI) and near infrared refraction (NIR) imaging, and a preparation method and the application thereof. The method is characterized in that macromolecules, namely synthetic polymers or biomacromolecules are used as a protecting agent; fluoride LaxGd1-xF3 is used as a matrix material, wherein x ranges from 0.1 to 0.9; neodymium ions, namely Nd3 <+> are used as a luminescent centre; and the rare earth nanoparticle is a water-soluble rare earth nanoparticle with the particle size of 10-100 nm. A fluorescence spectrum of the doped rare earth nanoparticle LaF3 / GdF3 : Nd has two very strong characteristic peaks (863 nm and 892 nm as well as1042 nm and 1057 nm) when being displayed in a near-infrared region with wavelength of 700-1200 nm, in-vitro magnetic resonance imaging data show that the rare earth nanoparticle has higher longitudinal relaxation rate, so that the rare earth nanoparticle can be used for preparing a near-infrared and magnetic resonance bimodal contrast agent for a living body.

The invention provides a contrast agent as well as a preparation method and an application thereof. The contrast agent is formed by taking Mn3[Co(CN)6]2 nanometer particles as an inner core and a silica coating layer as a casing. The contrast agent which is high in relaxation rate, low in toxicity and high in fluorescent quantum yield can be used for T1-T2 dual-mode magnetic resonance imaging, magnetic resonance angiography, multiband bioluminescence imaging and dual-photon bioluminescence imaging.

The invention discloses a bismuth sulfide / gadolinium oxide-entrapping ultrafine protein composite nanoparticle with a near-infrared photothermal effect and a multi-mode imaging function and a preparation method and application thereof. By formulation screening and process optimization, the bismuth sulfide / gadolinium oxide albumin ultrafine composite nanoparticle with the near-infrared photothermaleffect and the multi-mode imaging function is prepared in one step. The composite nanoparticle has good physicochemical stability, photostability, biocompatibility and tumor-targeting property, can remarkably enhance near-infrared fluorescence, photoacoustic, magnetic resonance, CT (computed tomography) and thermal signals at a tumor site, and realizes multi-mode-complemented tumor diagnosis, andmoreover, the composite nanoparticle can eliminate tumors under the excitation of near-infrared light; in particular, because the grain size of the nanoparticle is less than 5.5nm, the nanoparticle can be eliminated by the kidneys, and toxic and side effects are minor; a tumor can be diagnosed and treated at the same time, and the composite nanoparticle has a great potential in realizing accuratetumor diagnosis and treatment integration.

The invention discloses a precious metal / paramagnetic metal composite nanoparticle with a core-shell structure and application thereof. A preparation method for the precious metal / paramagnetic metal composite nanoparticle comprises the following steps: (a) preparing a precious metal nanoparticle with a particle size of 5 to 50 nm, wherein the precious metal is gold or silver; (b) taking a compound A containing a mercapto group and an amino group, allowing the precious metal nanoparticle to react with the compound A so as to obtain a product a and then allowing the product a to react with methyl acrylate so as to obtain a product b; (c) taking a compound C containing an azido group and an amino group and reacting the product obtained in the step (b) with the compound C so as to obtain an azido-surface-modified precious metal nanoparticle; (d) subjecting the azido-surface-modified precious metal nanoparticle prepared in the step (c) and a micromolecular ligand containing an alkynyl group to the Clicker reaction so as to obtain a product d; and (e) reacting the product d with a chloride of a paramagnetic metal so as to obtain the composite nanoparticle. The precious metal / paramagnetic metal composite nanoparticle can be used as an MRI and CT enhancement contrast agent.

The invention relates to a preparation method of a gadolinium oxide magnetic resonance imaging nano probe with good biocompatibility. The preparation method of the gadolinium oxide magnetic resonance imaging nano probe with good biocompatibility comprises the following steps: 1) in a breaker, dissolving biomacromolecules in water, and stirring until the biomacromolecules are completely dissolved; adding a Gd(NO3)3.6H2O aqueous solution into the biomacromolecule solution, uniformly stirring, adding a NaOH aqueous solution, then regulating pH to be 10, and continuously stirring for 1 hour at room temperature, so that a colourless liquid is obtained; 2) purifying the obtained impurity-containing gadolinium oxide nano probe, carrying out dialysis for 24 hours, and changing water every other 4 hours, so that the purified nano probe is obtained after dialysis is carried out; and 3) carrying out free-drying, so that a flocculent white solid product is obtained. The preparation method of the gadolinium oxide magnetic resonance imaging nano probe with good biocompatibility has the advantages of simplicity, simple preparation conditions, environment-friendly raw materials, good water solubility, high T1 relaxation rate and low potential biological toxicity, is convenient for large-scale production and has large development potential and great application value in the field of medical imaging.

The present invention relates to a magnetic resonance imaging (MRI) contrast agent including a gadolinium complex, more particularly to a DO3A-tranexamic acid or its ester compound, which is represented by the Chemical Formula 1. A DO3A-tranexamic acid or its ester compound may be prepared according to the present invention and a gadolinium complex may be prepared using the compound. An MRI contrast agent including the gadolinium complex prepared according to the present invention as an active ingredient has higher relaxivity as compared to the currently commercially available contrast agent. In addition, the MRI contrast agent according to the present invention has bifunctionality of liver-specific and blood-pool contrasting effect. Accordingly, since the MRI contrast agent including the gadolinium complex according to the present invention satisfies the key properties required for a contrast agent for MRI, it can be widely used as an MRI contrast agent and can provide enhanced contrasting effect as compared to the existing contrast agent.

The invention relates to the technical field of preparing a contrast agent by utilizing a hyperbranched polymer. A preparing method of the hyperbranched polymer includes reacting a lysine salt and caustic alkali in a mole ratio of 100:80-90 at 140-160 DEG C for 40-50 h in a protective atmosphere; mixing a hyperbranched polylysine skeleton and diethylenetriaminepentaacetic acid according to a mass ratio of at least 1:5 in water; reacting the mixture at room temperature for 6-8 h; mixing the first hyperbranched polylysine molecule and a gadolinium compound in water; reacting the mixture at 37-42 DEG C for 6-12 h, with the mass ratio of the first hyperbranched polylysine molecule to the gadolinium compound being 1:1-1:2; and mixing and reacting the second hyperbranched polylysine molecule and folic acid in a carbonate the pH value of which is 8-10 for 5-12 h. The hyperbranched polylysine contrast agent has good biocompatibility, low toxicity and a high relaxation rate and can be metabolized in vivo.

The invention relates to a magnetic nanometer material used for imaging and photothermal therapy and a preparation method and application of the magnetic nanometer material. The magnetic nanometer material used for imaging and photothermal therapy refers to nanometer iron oxide particles coated with melanin. The magnetic nanometer material is non-toxic, high in biocompatibility and capable of imaging. According to the preparation method, a one-step coprecipitation method is adopted to composite water-soluble Fe3O4@mel NCs. The magnetic nanometer material has the advantages of mildness and simplicity.

The invention discloses a method for preparing a paramagnetic polyphosphazene nanotube magnetic resonance imaging contrast agent. The method is characterized by firstly taking hexachlorocyclotriphosphazenes and 4,4'-dihydroxydiphenylsulfone as comonomers and triethylamine as an acid binding agent to carry out polymerization under room temperature to prepare the polyphosphazene nanotube and obtaining a polyphosphazene nanotube ligand after purifying the polyphosphazene nanotube; and then reacting the ligand with paramagnetic metal inorganic salt, finally centrifuging the reactant, washing the product three times respectively with water and absolute ethyl alcohol, thus obtaining the solid powder of the magnetic resonance imaging contrast agent after drying. The method is strong in operability, wide in application range, simple in equipment requirement, low in cost and high in yield and can be used for mass production in industry application. The magnetic resonance imaging contrast agent of the invention is a novel polymer nanotube magnetic resonance imaging contrast agent. The relaxation rate of the magnetic resonance imaging contrast agent is as high as 42.88-237.83mmol / L*s and is 12-65 times that of the commercial magnetic resonance imaging contrast agents Gd-DTPA (with relaxation rate of 3.64mmol / L*s).

The invention provides a diamino polyethylene glycol modified paramagnetic metal complex magnetic resonance imaging contrast agent, and aims at solving the problems of low relaxation rate, high toxicity and large dosage of a contrast agent in the prior art. The contrast agent is prepared by the following steps: reacting 1,4,7,10-tetrazacyclododecane-1,4,7,10-tetraacetic acid compound with diaminopolyethylene glycol with different molecular weights; preparing a macromolecular ligand through an amidation reaction; and forming a paramagnetic metal complex with paramagnetic metal elements Sc, Ti, V, Mn, Cu, Mo, Ru, Fe or positive trivalent or divalent ion of lanthanide rare-earth elements. The contrast agent has the advantages of high stability, water solubility, relaxation rate and small dosage.

A Gd doped composite nano-material is proportionally prepared from Gd and silicon oxide, and feature sits (2-7)-nm channels, high p[aramagnetism of Gd, high relaxation rate of tissue T1 and T2, and high compatibility to biologic macromolecule. Its preparing process is also disclosed.

The invention discloses a tumor-targeted magnetic resonance imaging and fluorescent supermolecular imaging contrast agent and preparation and application thereof. The tumor-targeted magnetic resonanceimaging and fluorescent supermolecular imaging contrast agent is characterized in that a water-soluble macromolecular skeleton material is modified by molecules with a specific binding function, andis self-assembled with corresponding ligand molecules to form supermolecular nanoparticles under the mutual action of a host and a guest, and the ligand molecules are modified with a paramagnetism material with an imaging function and a near-infrared fluorescent dye. The tumor-targeted magnetic resonance imaging and fluorescent supermolecular imaging contrast agent has the advantages that the tumor cells of a receptor with high expression specificity can be targeted; the magnetic resonance imaging and fluorescent double imaging functions are realized; the contrast agent can be used for the in-operation fluorescent guidance positioning and the post-operation magnetic resonance monitoring in the tumor cutting operation.

The invention relates to a HA-targeted layered doubled hydroxide-ultrafine iron nano material and preparation and applications thereof. The preparation is as follows: synthesizing an LDH-Fe3O4 nano composite material by a coprecipitation method; covalently bonding activated hyaluronic acid on the surface of an LDH laminate through a silane coupling agent; and finally, carrying out surface loadingof an anticancer drug. The nano-material particles are uniformly distributed, and can enhance the MR imaging effect of the tumor part in an animal body. The LDH-Fe3O4-HA NPs is used as a carrier of ananticancer drug doxorubicin DOX, not only has sensitive pH response and release characteristics, but also can carry out specific recognition on tumor cells expressed by CD44 receptors so as to achieve the idealization effect of efficiently inhibiting tumors.

The invention relates to the field of pharmacy and particularly relates to a gadolinium-series contrast agent with a carboxylated short single-walled carbon nanotube modified by hyaluronic acid as a carrier as well as a preparation method and an application of the gadolinium-series contrast agent, which can effectively solve the problem that an existing contrast agent is poor in technical targeting property, short in half-life peroid, low in relaxation efficacy and large in toxic and side effects. According to the technical scheme, the preparation method comprises the following steps: covalently connecting hyaluronic acid containing natural polysaccharide molecules with a carboxylated short single-walled carbon nanotube through taking alkylene diamine as a connecting arm, then adhering gadolinium trichloride onto the modified carbon nanotube in a physical method, and forming a nanosuspension with water, thus obtaining the gadolinium-series contrast agent with the carboxylated short single-walled carbon nanotube modified by hyaluronic acid as the carrier. The gadolinium-series contrast agent with the carboxylated short single-walled carbon nanotube modified by hyaluronic acid as the carrier has good chemical stability and good biocompatibility, can be effectively used as a magnetic resonance contrast agent in tumor diagnosis and is an innovation on a tumor contrast agent.

There is provided a hyperbranched polymer having a nitroxyl group. A hyperbranched polymer comprising at least one organic radical structure (nitroxyl group) of Formula (1), Formula (2) or Formula (3):and having a weight average molecular weight measured by gel permeation chromatography in a converted molecular weight as polystyrene of 500 to 5,000,000.

The invention belongs to the technical field of biological medicine, and particular relates to a magnetism polymer nanometer microsphere material capable of degrading ring structure , as well as a preparation method and application of the magnetism polymer nanometer microsphere material. The backflow precipitation polymerization technology is adopted in the invention, Fe3O4 magnetic clusters stabilized by polyglutamate or agarose are used as cores; a polymer shell which is not crosslinked is firstly wrapped on the exterior, a new polymer shell with crosslinked disulfide bond is secondly wrapped, alcohol or water is used for etching the polymer not crosslinked, and the degradable magnetism polymer microcapsules with crosslinked disulfide bond are obtained. The method provided by the invention is quick and simple in post-treatment, requires no etching using a strong acid or a strong alkali, and is safe and efficient; the prepared material can is very good monodispersity, and can be applied to the fields of ultrasound and magnetic resonance image formation contrast agent and medicine carrier.

The present invention discloses a nano composite. The nano composite is characterized by comprising photothermal conversion nanoparticles, a fusion agent, a paramagnetic component and an active targeting antibody; wherein the active targeting antibody contains carboxyl groups and the fusion agent contains amino groups; the carboxyl groups of the active targeting antibody is linked to the amino groups in the fusion agent. The nano composite has an active targeting property, integrates a magnetic effect and a photothermal effect in one, and particularly has better affinity for CD 133 receptor high-expression pancreatic cancer and related cancers. The present application also discloses a preparation method and an application of the nano composite. The method is mild in conditions, not high inrequirements on equipment, operation, environment, etc., economic and easily-obtained in raw materials, easy for implementation and good in stability and reproducibility. When the nano composite is used for magnetic resonance imaging and photothermal integration materials, the nano composite can effectively shorten T1 relaxation time, remarkably improves magnetic resonance T1 relaxation rate, andis better in T1 imaging, higher in contrast and also excellent in a near infrared photothermal effect.

The invention provides a double-layered core-shell structure molecular carrier. The double-layered core-shell structure molecular carrier is characterized in that a modified sodium gadolinium tungstate nano-rod NaxGdWO3 is used as an inner core and the outer surface of the inner core is coated with mesoporous silicon dioxide; a double-layered structure is WCMSNs. The molecular carrier not only canbe used for carrying out magnetic resonance imaging and photo-thermally burning tumor cells to die, but also can load various medicines or target molecules, so that drug treatment or targeting localization is carried out on the basis of the magnetic resonance imaging and photo-thermal treatment.