A nanoparticle includes a metal-based core, a first coating layer substantially covering the metal-based core to generate a coated metal-based core, and a second coating layer at least partially covering the coated metal-based core, wherein the metal-based core comprises at least one transition metal, and wherein the metal-based core comprises the at least one transition metal substantially in a state of zero oxidation.

A method of tracking immune cells to detect immune response. The method including steps of identifying a patient having a disease associated with an organ; administering biocompatible magnetic nanoparticles into the blood stream of the patient; and obtaining a magnetic resonance image of the organ. The presence of hyperintense or hypointense spots in the magnetic resonance image indicates immune response in the patient.

Disclosed are a targeting aptamer for atherosclerosis and a preparation method and application thereof. The targeting aptamer is a targeting aptamer fragment for atherosclerosis obtained through screening of macrophage-derived foam cells together with reverse screening of smooth muscle cells, endothelial cells, and THP-1 cells using a SELEX method; and the use of the targeting aptamer in preparation of an MRI targeting nano-contrast agent for atherosclerosis allows the specific binding of the MRI targeting nano-contrast agent for atherosclerosis only with the macrophage-derived foam cells, and allows high specific binding thereof with vascular tissues with AS lesion, this improving targeting effect of the MRI targeting nano-contrast agent for atherosclerosis and realizing early specific diagnosis of arterial sclerosis.

A low temperature, aqueous synthesis of polyhedral iron oxide nanoparticles (IONPs) is presented. The modification of the co-precipitation hydrolysis method with Triton X surfactants results in the formation of crystalline polyhedral particles. The particles are herein termed iron oxide nanobricks (IONBs), as the varieties of particles made are all variations on a simple brick-like, polyhedral shape such as rhombohedral shape or parallelogram as evaluated by TEM. These IONBs can be easily coated with hydrophilic silane ligands, allowing them to be dispersed in aqueous media. The dispersed particles are investigated for potential applications as hyperthermia and T.sub.2 MRI contrast agents. The results demonstrate that the IONBs perform better than comparable spherical IONPs in both applications, and show r.sub.2 values amongst the highest for iron oxide based materials reported in the literature.

The present invention provides methods for detecting an enzymatic activity, the method including combining at least one magnetic particle to an enzyme substrate to form a magnetically modified substrate, reacting the magnetically modified substrate with at least one enzyme; and detecting a change in a magnetic property of the magnetically modified substrate or its cleavage products, thereby detecting an activity of said at least one enzyme, wherein the method may be applied to a human subject to detect a disease selected from the group consisting of rheumatitis, arthritis, an injury, Dupuytren's disease, Peyronie's disease, a collagen related disease, steatosis, fibrosis, cirrhosis, metastasis, tissue regeneration, cancer, coronary disease, a liver disease, a metabolic condition, an infection and an inflammatory disease.

The invention relates to aqueous dispersions, comprising particles based on a magnetic iron oxide with dimensions of 20 nm, the surface of which is modified by the grafting of aminated groups R with a covalent bonding to the surface of said particles, wherein the isoelectronic point of particles with such a modified surface is 10. The invention further relates to a method for production of said aqueous suspensions and a method for modification of the surface of the particles present in said dispersions, in particular, by the immobilisation of polysaccharides such as dextrans, particularly for the formulation of magnetic compositions which may be administered in vivo and in particular for the formulation of injectable compositions of contrast agents for MRI.

Compositions of nanoparticles functionalized with at least one zwitterionic moiety, methods for making a plurality of nanoparticles, and methods of their use as diagnostic agents are provided. The nanoparticles have characteristics that result in minimal retention of the particles in the body compared to other nanoparticles. The nanoparticle comprising a nanoparticulate transition metal oxide covalently functionalized with a silane-functionalized non-targeting zwitterionic moiety.

A silica particle for medical imaging includes a bridged silane fluorescent dye incorporated throughout the particle matrix. Copolymerization of a bridged silane fluorescent dye (e.g., (RO).sub.3SiRSi(OR).sub.3, where R is a fluorescent organic bridging group, and where R is a methyl or ethyl group) and a tetralkoxysilane (e.g., Si(OR).sub.4, where R is a methyl or ethyl group) generates particles of a predetermined size and shape. This leaves the surface of each particle available for further modification to facilitate dispersion of the particle into different media. Hence, a surface modifier may be subsequently bonded onto the particle surface. In some embodiments, poly(ethylene glycol) is selected as the surface modifier to increase dispersion of the silica particle in an aqueous media. In some embodiments, the particle is porous allowing for an additional functionality (e.g., a secondary imaging material, such as magnetic nanoparticles, and/or a pharmaceutical drug) to be loaded within the pores.

A silica particle for medical imaging includes a bridged silane fluorescent dye incorporated throughout the particle matrix. Copolymerization of a bridged silane fluorescent dye (e.g., (RO).sub.3SiRSi(OR).sub.3, where R is a fluorescent organic bridging group, and where R is a methyl or ethyl group) and a tetralkoxysilane (e.g., Si(OR).sub.4, where R is a methyl or ethyl group) generates particles of a predetermined size and shape. This leaves the surface of each particle available for further modification to facilitate dispersion of the particle into different media. Hence, a surface modifier may be subsequently bonded onto the particle surface. In some embodiments, poly(ethylene glycol) is selected as the surface modifier to increase dispersion of the silica particle in an aqueous media. In some embodiments, the particle is porous allowing for an additional functionality (e.g., a secondary imaging material, such as magnetic nanoparticles, and/or a pharmaceutical drug) to be loaded within the pores.