The present disclosure provides stimuli-responsive particles, methods of preparing stimuli-responsive particles, and methods of using the stimuli-response particles. Unlike conventional platforms, (e.g., polymers, liposomes, dendrimers) the particles of the present disclosure have precise size control of the particle diameter, high uniformity, high stability, high active agent uptake capacity, minimal premature active agent leakage, biocompatibility, and biodegradability. Additionally, the present disclosure provides magnetic resonance imaging (MRI) systems and methods of using the MRI systems in combination with the stimuli-responsive particles described herein.

Provided is a T1 contrast agent for magnetic resonance imaging. The T1 contrast agent includes fine iron oxide nanoparticle cores and micelles encapsulating the core particles. The micelles include a nonionic surfactant consisting of a hydrophilic moiety containing at least two chains and a hydrophobic moiety containing at least one C.sub.10-C.sub.30 hydrocarbon chain. The T1 contrast agent of the present invention is a novel one based on fine iron oxide nanoparticles that can replace conventional gadolinium-based T1 contrast agents. The T1 contrast agent based on fine iron oxide nanoparticles according to the present invention is harmless to humans, is rapidly distributed in the blood, and has a uniform size, ensuring its uniform contrast effect. In addition, the T1 contrast agent of the present invention enables image observation for at least 1 hour to up to 2 hours and is excreted through the kidneys and liver. Therefore, the T1 contrast agent of the present invention avoids the problems encountered in conventional gadolinium-based contrast agents.

The present invention relates to a magnetic resonance imaging (MRI) contrast agent, particularly an MRI contrast agent derived from nanoparticle that is porous first metal-doped second metal oxide nanoparticle with a central cavity, and a method for producing the same. The MEI contrast agent made in accordance with the present invention can be used not only as a drug-delivery agent for therapy but also as an MRI contrast agent for diagnosis.

Polyarginine-coated nanoparticle, and methods for making and using the nanoparticle. The nanoparticle can have a core that includes a material that imparts magnetic resonance imaging activity to the particle and, optionally, include one or more of an associated therapeutic agent, targeting agent, and diagnostic agent.

Disclosed herein are nanoconstructs comprising a nanoparticle, coated with additional agents such as cationic polymers, stabilizers, targeting molecules, labels, oligonucleotides and small molecules. These constructs may be used to deliver compounds to treat solid tumors and to diagnose cancer and other diseases. Further disclosed are methods of making such compounds and use of such compounds to treat or diagnose human disease.

The present invention relates to a magnetic resonance imaging (MRI) contrast agent, particularly a metal oxide nanoparticle-based T1-T2 dual-mode MRI contrast agent that can be used not only as a T1 MRI contrast agent but also as a T2 MRI contrast agent, and a method for producing the same. The metal oxide nanoparticle-based T1-T2 dual-mode MRI contrast agent can provide more accurate and detailed information associated with disease than single MRI contrast agent by the beneficial contrast effects in both T1 imaging with high tissue resolution and T2 imaging with high feasibility on detection of a lesion.

The present system relates to a mains-powerable, compact and customizable alternating current magnetic field plate for magnet-assisted transfection of genes to target cells. Magnet plate is based on at least one alternating current electromagnet comprising a laminated steel stack core and a multi-layer, multi-turn coil wound longitudinally therearound. The system includes a voltage rating adjustment controller, as well as a current adjuster for selective control of magnetic force applied to genetic material for delivery. Rapid magnetic field polarity switching exacts lateral motion efficiently and uniformly, thus improving the distribution of means, such as SPIONS, used to transfect cells with genes of interest, and in turn enhancing gene delivery and tissue localization, especially for hard-to-transfect genes, compared to DC magnet plates.

There are described magnetic nanoparticles the surface of which is functionalized with catechol and constructs comprising a plurality of said nanoparticles encapsulated in a biocompatible polymer matrix, wherein a molecule with therapeutic action is optionally dispersed, said polymer matrix optionally being in turn further functionalized; there are further described cells of the immune system incorporating said polymeric constructs giving rise to their engineering.

Disclosed are methods, compositions, reagents, systems, and kits to prepare nitroxide-functionalized brush-arm star polymer organic radical contrast agent (BASP-ORCA) as well as compositions and uses thereof. Various embodiments show that BASP-ORCA display unprecedented per-nitroxide and per-molecule transverse relaxivities for organic radical contrast agents, exceptional stability, high water solubility, low in vitro and in vivo toxicity, and long blood compartment half-life. These materials have the potential to be adopted for tumor imaging using clinical high-field .sup.1H MRI techniques.

The present disclosure provides for compositions including coated magnetic particles (e.g., coated magnetic nanoparticles), methods of using the coated magnetic particles such as imaging a subject (e.g., a mammal), tissue, organ, or the like, a cryopreservation composition including the coated magnetic particles, methods of use of the cryopreservation composition in biomaterials (e.g., tissue, organ, and the like), methods of making the composition and cryopreservation composition, and the like.