A marker for imaging includes a bio-dissolvable material and a contrast agent configured to provide contrast during an imaging procedure. A method can include forming a marker for imaging from a bio-dissolvable material and impregnating the bio-dissolvable material with a contrast agent. A method can include implanting a bio-dissolvable marker for imaging into a patient.

Provided herein are magnetic resonance imaging (MRI) contrast agents comprising a compound having a structure represented by: Y—X—Z, wherein, X is: Fe(III) or Mn(II), and Y and Z are each independently selected from pyrophosphate and bisphosphonate (e.g., 1-hydroxybisphosphonate), or a pharmaceutically acceptable hydrate and/or salt thereof. Methods of use of the MRI contrast agent are also provided.

The present invention relates to compounds that are useful as metal ligands and which either contain a molecular recognition moiety or can be bound to a molecular recognition moiety and methods of making these compounds. Once the compounds that contain a molecular recognition moiety are coordinated with a suitable metallic radionuclide, the coordinated compounds are useful as radiopharmaceuticals in the areas of radiotherapy and diagnostic imaging. The invention therefore also relates to methods of diagnosis and therapy utilising the radiolabelled compounds of the invention.

The subject invention pertains to a modified MC1R peptide ligand comprising a peptide that is a melanocortin 1 receptor (MC1R) ligand and a functionality or linker, such as a click functionality, for conjugation to a surface or agent. The modified MC1R peptide ligand can be coupled, e.g., via a click reaction with a complementary click functionality attached, to a moiety to form an MC1R-targeted agent. Drugs, contrast agents, polymers, particles, micelles, surfaces of larger structures, or other moieties can be targeted to the MC1R. The subject invention also pertains to a MC1R peptide ligand-micelle complex comprising a peptide that is a melanocortin 1 receptor ligand connected via a click reaction product to a micelle. The micelle is stable in vivo and can target melanoma tumor cells by association of the peptide ligand with the MC1R or the tumor and selectively provide a detectable and/or therapeutic agent (such as an imageable contrast agent and/or anti-cancer agent) selectively to the tumor cell.

An MRI contrast composition includes a liposome and a europium metal complex disposed within the liposome. The europium metal complex includes a europium metal ion and a multi-dentate ligand selected from the group consisting of cryptands and thiacryptands and one or more counter-ions that balances a charge of the europium metal ion and the multi-dentate ligand, the europium metal ion being switchable between a 2÷ and 3÷ oxidation state. The contrast composition advantageously provides an oxidation-responsive dual-mode contrast agent because it would enhance either T.sub.1-weighted images or CEST images depending on the oxidation state of Eu.

The present invention relates to a method of preparation of formulations of lanthanide metal complexes of macrocyclic chelators which further comprise a small excess of free chelator. The method uses a solid phase-bound scavenger chelator to remove excess lanthanide metal ions, prior to the addition of a defined excess chelator. Also provided is a method of preparation of MRI contrast agents, together with solid-phase bound chelator meglumine salts useful in the methods.

The present disclosure provides a method of DDCE-MRF. The method can include: a) introducing two or more contrast agents to a region of interest (ROI) of a subject, the two or more contrast agents having different relaxivities; b) measuring a T1 relaxation time and a T2 relaxation time for locations within the ROI using magnetic resonance fingerprinting (MRF); c) determining, using equations that relate the different relaxivities, the T1 relaxation time, the T2 relaxation time, and concentrations of the two or more contrast agents, the concentrations of the two or more contrast agents for each of the locations within the ROI; and d) producing an image depicting the ROI based, at least in part, on the concentrations of the two or more contrast agents.

Compounds may have at least two structural units, which may be referred to as ligands. Each structural unit includes at least one spacer group and two or more donor groups. Compounds may have two or more iron(III) cations, one or more of which may be a high-spin iron(III) cation or high-spin iron(III) cations, two or more gallium(III) cations, or at least one iron(III) cation, one or more of which may be a high-spin iron(III) cation or high-spin iron(III) cations, and at least one gallium(III) cation, where the iron(III) cation(s) and/or the gallium(III) cation(s) coordinate to the donor groups. The compounds may be self-assembled cages. A composition may include one or more of the compound(s) and a pharmaceutically accepted carrier. Methods of imaging use one or more of the compound(s) and/or one or more of the composition(s).

The present invention concerns a luminescent particle comprising a nanoparticle of formula
A.sub.1-xLn.sub.xVO.sub.4(1-y)(PO.sub.4).sub.y  (I)
in which A is selected from yttrium (Y), gadolinium (Gd), lanthanum (La), and mixtures thereof; Ln is selected from europium (Eu), dysprosium (Dy), samarium (Sm), neodymium (Nd), erbium (Er), ytterbium (Yb), and mixtures thereof; 0<x<1; and 0≤y<1; characterized in that the nanoparticle on its surface has tetraalkylammonium cations in an amount such that said nanoparticle has a zeta potential, ζ, of less than or equal to −28 mV in an aqueous medium with a pH≥5, more particularly with a pH≥5.5, and with an ionic conductivity >100 μS.Math.cm.sup.−1. It also concerns a method for preparing such luminescent particles, a colloidal suspension of these particles, and the use thereof as a diagnostic agent, and also a diagnostic kit comprising such luminescent particles.

Provided herein are examples of metal chelating ligands that have high affinity for manganese. The resultant metal complexes can be used as MRI contrast agents, and can be functionalized with moieties that bind to or cause relaxivity change in the presence of biochemical targets.