The invention relates to highly fluorescent metal oxide nanoparticles to which biomolecules and other compounds can be chemically linked to form biocompatible, stable optical imaging agents for in vitro and in vivo applications. The fluorescent metal oxide nanoparticles may also be used for magnetic resonance imaging (MRI), thus providing a multi modality imaging agent.

Recombinant host cells are provided. The cell genome contains heterologous gene expression cassettes capable of being expressed in the host cell, where the gene expression cassettes encode a nucleic acid sequence encompassing at least 80% of the full-length sequence of the mamAB operon, the mamGDFC operon, and the tmms6 operon of a magnetotactic alphaproteobacterium, respectively. The cells may further comprise gene expression cassettes capable of being expressed in the host cell, where the gene expression cassettes encode a nucleic acid sequence encompassing at least 80% of the full-length sequence of the mamXY operon and/or the feoABI operon of a magnetotactic alphaproteobacterium; where the recombinant host cell, upon expression of the gene expression cassettes in their entirety, is capable of producing magnetic nanoparticles. Preferably, the recombinant host cell is derived from Rhodospirillum rubrum. Methods of producing these recombinant host cells by genetic transposition are provided.

Methods, systems, and devices are disclosed for fabricating and utilizing nanoscale material structures such as nanoflakes and nanoshells.

A method for forming a benzophenone derivative product that resistant to absorption by living tissue that includes binding a benzophenone-containing compound with an oxide-containing particle by acid-catalyzed condensation or Friedel-Crafts acetylation to provide a benzophenone derivative having a microscale size. The benzophenone derivative can then be mixed into a lotion. The microscale size of the benzophenone derivative obstructs absorption by cell tissue. The benzophenone derivative may be an oxybenzone derivative.

A particle usable as T.sub.1 and T.sub.2 contrast agents is provided. The particle is a gadolinium silicide (Gd.sub.5Si.sub.4) particle that is ferromagnetic at temperatures up to 290 K and is less than 2 m in diameter. An MRI contrast agent that includes a plurality of gadolinium silicide (Gd.sub.5Si.sub.4) particles that are less than 1 m in diameter is also provided. A method for creating gadolinium silicide (Gd.sub.5Si.sub.4) particles is also provided. The method includes the steps of providing a Gd.sub.5Si.sub.4 bulk alloy; grinding the Gd.sub.5Si.sub.4 bulk alloy into a powder; and milling the Gd.sub.5Si.sub.4 bulk alloy powder for a time of approximately 20 minutes or less.

The objective of the present invention to provide a method for accurately and safely specifying a leakage part of cerebrospinal fluid in a cerebrospinal fluid hypovolemia patient, and a method for effectively treating cerebrospinal fluid hypovolemia with utilizing the specifying method. The method for specifying a leakage part of cerebrospinal fluid in a cerebrospinal fluid hypovolemia patient according to the present invention is characterized in comprising the steps of injecting saline into a bone-marrow space of a spine of the cerebrospinal fluid hypovolemia patient, and detecting the cerebrospinal fluid or the injected saline leaked from a dura mater of the spine to specify the leakage part of the cerebrospinal fluid.

Provided herein are therapeutic nanoparticles having a diameter of between 10 nm to 30 nm, and containing a polymer coating, and a nucleic acid containing a sequence complementary to a sequence within a micro-RNA identified as having a role in cancer cell metastasis or anti-apoptotic activity in a cancer cell (e.g., miR-10b) or a sequence within an mRNA encoding a pro-apoptotic protein that is covalently linked to the nanoparticle. Also provided are pharmaceutical compositions containing these therapeutic nanoparticles. Also provided herein are methods of decreasing cancer cell invasion or metastasis in a subject having a cancer and methods of treating a metastatic cancer in a lymph node in a subject that require the administration of these therapeutic nanoparticles to a subject.

Nanoparticles include a core and one or more targeting moieties, as well as one or more contrast agents or one or more therapeutic agents. The contrast agents or therapeutic agents may be contained or embedded within the core. If the nanoparticle includes therapeutic agents, the agents are preferably released from the core at a desired rate. The core may be biodegradable and may release the agents as the core is degraded or eroded. The targeting moieties preferably extend outwardly from the core so that they are available for interaction with cellular components, which interactions will target the nanoparticles to the appropriate cells, such as apoptotic cells; organelles, such as mitochondria; or the like. The targeting moieties may be tethered to the core or components that interact with the core.

The objective of the present invention to provide a method for accurately and safely specifying a leakage part of cerebrospinal fluid in a cerebrospinal fluid hypovolemia patient, and a method for effectively treating cerebrospinal fluid hypovolemia with utilizing the specifying method. The method for specifying a leakage part of cerebrospinal fluid in a cerebrospinal fluid hypovolemia patient according to the present invention is characterized in comprising the steps of injecting saline into a bone-marrow space of a spine of the cerebrospinal fluid hypovolemia patient, and detecting the cerebrospinal fluid or the injected saline leaked from a dura mater of the spine to specify the leakage part of the cerebrospinal fluid.

Lipid-based nanoparticle compositions are provided. The compositions generally comprise lipid-hydrophilic polymer-amyloid binding ligand conjugates, and may be liposomal compositions. The compositions, including the liposomal compositions, may be useful for imaging and/or the treatment of amyloid- plaque deposits characteristic of Alzheimer's Disease.