The present application discloses treating water insoluble nanoparticles, particularly nanoparticles of metals and metal compounds which find utility in diagnostic imaging such as MR and X-ray imaging, with an alpha-hydroxyphosphonic acid conjugate with a hydrophilic moiety to render the nanoparticles sufficiently hydrophilic to find utility in diagnostic imaging. Among the modified hydrophilic nanoparticles disclosed are those in which the hydrophilic moieties of the modifying conjugate are ethylene oxide based polymers and copolymers and zwitterions and the nanoparticles are composed of transition metal oxides such as superparamagnetic iron oxide and tantalum oxide. Disclosed are nanoparticles which are sufficiently hydrophilic to form stable aqueous colloidal suspensions. Also disclosed is diagnostic imaging such as MR and X-ray using the modified hydrophilic nanoparticles as contrast agents.

A non-pyrogenic preparation containing nanoparticles synthesized by magnetotactic bacteria for medical or cosmetic applications. The nanoparticles are constituted by a crystallized mineral central part including predominantly an iron oxide, as well as a surrounding coating without material from the magnetotactic bacteria.

Provided is a novel nanoparticle, a contrast agent for magnetic resonance imaging containing the same, and a zwitterionic ligand compound used in production of the nanoparticle. The contrast agent for MRI of the present invention can be suitably used as a contrast agent for MRI in a medical field. The nanoparticle and the zwitterionic ligand compound of the present invention are applicable to various pharmaceutical compositions and the like, including a contrast agent for MRI, and can be used widely in the fields of pharmaceuticals, biotechnology, and the like, including various diagnosis methods and examination reagents.

A non-pyrogenic preparation containing nanoparticles synthesized by magnetotactic bacteria for medical or cosmetic applications. The nanoparticles are constituted by a crystallized mineral central part including predominantly an iron oxide, as well as a surrounding coating without material from the magnetotactic bacteria.

[Problem]

A novel method for producing a nanoparticle having a metal particle which contains iron oxide to which one or more hydrophilic ligands are coordination bonded is provided, where the nanoparticle is useful as a contrast agent for magnetic resonance imaging.

[Means for Solution]

As the novel method for producing a nanoparticle having a metal particle which contains iron oxide to which one or more hydrophilic ligands are coordination bonded, by performing ligand exchange to a hydrophilic ligand from an iron oxide nanoparticle having a surface to which a hydrophobic ligand is coordination bonded in one step using a phase transfer catalyst, it is possible to expect shortening of production processes and reduction of hydrophilic ligands used.

Furthermore, by producing an iron oxide nanoparticle having a surface to which a hydrophobic ligand is coordination bonded using a dropwise addition method, it is possible to avoid a rapid temperature rise and a reaction at a high temperature of 200° C. or higher, which is more advantageous for industrial production.

A non-pyrogenic preparation containing nanoparticles synthesized by magnetotactic bacteria for medical or cosmetic applications. The nanoparticles are constituted by a crystallized mineral central part including predominantly an iron oxide, as well as a surrounding coating without material from the magnetotactic bacteria.

A non-pyrogenic preparation containing nanoparticles synthesized by magnetotactic bacteria for medical or cosmetic applications. The nanoparticles are constituted by a crystallized mineral central part including predominantly an iron oxide, as well as a surrounding coating without material from the magnetotactic bacteria.

Dendronized metallic oxide nanoparticles, a process for preparing the same and their uses.

A non-pyrogenic preparation containing nanoparticles synthesized by magnetotactic bacteria for medical or cosmetic applications. The nanoparticles are constituted by a crystallized mineral central part including predominantly an iron oxide, as well as a surrounding coating without material from the magnetotactic bacteria.

A non-pyrogenic preparation containing nanoparticles synthesized by magnetotactic bacteria for medical or cosmetic applications. The nanoparticles are constituted by a crystallized mineral central part including predominantly an iron oxide, as well as a surrounding coating without material from the magnetotactic bacteria.