A construct for detecting cellular membrane potential includes a nanoparticle operable as an electron donor; a modular peptide attached to the nanoparticle, the peptide comprising a nanoparticle association domain, a motif configured to mediate peptide insertion into the plasma membrane, and at least one attachment point for an electron acceptor positioned at a controlled distance from the nanoparticle; and an electron acceptor. The nanoparticle can be a quantum dot and the electron acceptor can be C.sub.60 fullerene. Emission correlates with cellular membrane potential.

The invention provides a process for the production of nanoparticles as well as a device that is disposed for the production of the nanoparticles. The process is especially characterized in that the nanoparticles are pure, especially free from organic carbon compounds, preferably carbon-free, and are obtained continuously. The nanoparticles which are obtainable by the process of the invention are characterized in that they are present without an organic ligand in suspension and are especially preferred stable as a suspension against agglomeration, wherein the medium having the particles suspended therein is free from organic carbon compounds, especially carbon-free.

A method for surface modification of nanoparticles includes the separate steps of removing ligands from the surface of the nanoparticles to form ligand-free nanoparticles, and mixing new ligands with the ligand-free nanoparticles to form modified nanoparticles.

Disclosed herein are antibody-nanoparticle conjugates that include two or more nanoparticles (such as gold, palladium, platinum, silver, copper, nickel, cobalt, iridium, or an alloy of two or more thereof) directly linked to an antibody or fragment thereof through a metal-thiol bond. Methods of making the antibody-nanoparticle conjugates disclosed herein include reacting an arylphosphine-nanoparticle composite with a reduced antibody to produce an antibody-nanoparticle conjugate. Also disclosed herein are methods for detecting a target molecule in a sample that include using an antibody-nanoparticle conjugate (such as the antibody-nanoparticle conjugates described herein) and kits for detecting target molecules utilizing the methods disclosed herein.

The invention relates to a method for the absolute quantification of at least one analyte by means of a rapid test, in particular by spectroscopic determination. In order to provide a method and a device for the absolute quantification of analytes and to enable the creation of a database for the improved individual dosing of therapeutics, whereby a particularly accurate quantification of at least one analyte is possible in a simple manner, particularly inexpensively, particularly quickly and at any location without the need for a laboratory, it is provided, that at least one nanomaterial is used as a luminescent substance for quantification, which interacts directly or indirectly with the analyte, wherein at least one signal generated by the nanomaterial is measured and wherein in addition an internal and/or external standard series, in particular by means of Raman-labeled targets and/or fluorescence-labeled targets, is measured and subsequently the generated signal is standardized or referenced on the basis of the internal and/or external standard series, so that an absolute quantification is achieved.

Gold nanoparticles functionalized with thiolated, bidentate Schiff base ligands. The Schiff base ligands form a ligand monolayer surrounding and binding to the surface of a gold nanoparticle core through AuS linkages. The functionalized gold nanoparticle composites have a spherical shape, an average diameter of 7-15 nm and a narrow particle size distribution. Methods of assessing these functionalized gold nanoparticle composites as fluorescent probes in Fe(III) chemosensing applications, methods of preparing the functionalized gold nanoparticle composites and methods of detecting Fe(III) ions with the same are also provided.

The present invention provides nanoparticles including a metallic core having a length along each axis of from 1 to 100 nanometers and a coating disposed on at least part of the surface of the metallic core, wherein the coating comprises polydopamine, along with methods for making and using such nanoparticles. The metallic core may be gold, silver or iron oxide and the polydopamine coating may have other substances bound to it, such as silver, targeting ligands or antibodies, or other therapeutic or imaging contrast agents. The disclosed nanoparticles can be targeted to cells for treating cancer or bacterial infections, and for use in diagnostic imaging.

The invention relates to a conjugate which comprises an MRI contrast agent component comprising a nanoparticle, which nanoparticle comprises a metal or a metal compound, and a hypoxia targeting moiety which is conjugated to the MRI contrast agent component, especially wherein said nanoparticle comprises iron oxide and a biocompatible coating and wherein said hypoxia targeting moiety is a nitroimidazole. Also provided is the use of a said conjugate in a method of imaging a subject, a method of de-testing hypoxia, and a method of evaluating the activity of a pharmaceutical. Said conjugate is also of use in diagnosis.

Provided is a method of magnetically controlling a magnetic structure, the method including: providing a solution containing magnetic structures, each including a magnetic axis in which magnetic nanoparticles are arranged; and controlling movements of the magnetic structures by applying an external magnetic field to the solution.

A composition is disclosed which is capable of being used for detection, comprising a noble metal nanoparticle. The inventive compositions exhibit little interaction with serum proteins while exhibiting pH-dependent adsorption onto live cell membranes. The nanoparticles of the claimed invention are capable of interacting with cell membranes, which in turn permits the advantages of nanoparticle bio-imaging to be extended to many pH dependent biological processes such as targeting acidic tumor microenvironment.