A compound is disclosed that can be used as an anti-inflammatory agent, a cyclooxygenase-2 inhibitor, a therapeutic agent for brain diseases, or a MRI contrast medium. The compound can have the structure represented by chemical formula 1.

The present disclosure provides a pH and oxygen dual-sensitive magnetic resonance imaging contrast agent and a preparation method thereof, which is a dual-modal nanoparticle contrast agent with .sup.19F signal and CEST dual signal (.sup.19F-CEST), a CEST contrast agent that is dual-sensitive to pH and oxygen. The preparation method comprises: mixing a variety of phospholipid surfactants and cholesterol well to obtain a blend of phospholipid surfactants, which is dissolved in chloroform or a mixed solvent of chloroform and methanol, evaporated to dryness with a rotary evaporator and dried overnight in a vacuum oven at 40 C. after adding rhodamine, finally, it is dispersed in water containing glycerin by mechanical dispersion or ultrasonic vibration to obtain a lipid modifier; mixing perfluorocarbon, the lipid modifier obtained in step (1), glycerin, and water and ultrasonically mixing well with a probe, and extruding with an extruder to prepare a perfluorocarbon nanoemulsion.

The disclosure relates in some aspects to imaging agents, and in particular, imaging agents for sensing of calcium signaling. According to some embodiments of the disclosure, contrast agents for magnetic resonance imaging and related technologies are provided, and methods of making and using the contrast agents.

Provided herein are MRI contrast agents that are conditionally activated by an enzyme from a reporter gene coupled to a gene of interest. In some embodiments, provided herein is a platform where a substrate (blocking access of water to a Gd(III) ion) is removed by an enzyme that can be changed to accommodate a number of gene therapy targets.

An object of the present invention is to provide a halogenated biotin-modified dimer, which is capable of imaging diagnosis or treatment by labeling with a halogen, a biotin-modified dimer having a high affinity for a mutant streptavidin with a low affinity for natural biotin. The present invention provides a compound represented by the following formula (1) or a salt thereof:

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wherein the meaning of each symbol is the same as that described in the specification.

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.

Blood-brain barrier permeable peptide compositions that contain variable antigen binding domains from camelid and/or shark heavy-chain only single-domain antibodies are described. The variable antigen binding domains of the peptide compositions bind to therapeutic and diagnostic biomarkers in the central nervous system, such as the amyloid-beta peptide biomarker for Alzheimer's disease. The peptide compositions contain constant domains from human IgG, camelid IgG, and/or shark IgNAR. The peptide compositions include heavy-chain only single-domain antibodies and compositions with one or more variable antigen binding domain bound to one or more constant domains.

The invention relates to the use of tetrapyrroles conjugated compounds as contrast agent in magnetic resonance imaging (MRI). In particular conjugates of natural hemin that can be embedded in gels and implants to image local delivery in MRI.

Alkylphosphocholine analogs incorporating a chelating moiety that is chelated to gadolinium are disclosed herein. The alkylphophocholine analogs are compounds having the formula:

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or a salt therof. R.sub.1 includes a chelating agent that is chelated to a gadolinium atom; a is 0 or 1; n is an integer from 12 to 30; m is 0 or 1; Y is H, OH, COOH, COOX, OCOX, or OX, wherein X is an alkyl or an arylalkyl; R.sub.2 is N.sup.+H.sub.3, N.sup.+H.sub.2Z, N.sup.+HZ.sub.2, or N.sup.+Z.sub.3, wherein each Z is independently an alkyl or an aroalkyl; and b is 1 or 2. The compounds can be used to detect solid tumors or to treat solid tumors. In detection/imaging applications, the gadolinium emits signals that are detectable using magnetic resonance imaging. In therapeutic treatment, the gadolinium emits tumor-targeting charged particles when exposed to epithermal neutrons.

The present invention relates to an 18F-labelled compound, and a use thereof. The compound selectively binds to a prostate-specific membrane antigen (PSMA), and enables the acquisition of clear prostate cancer images in a short time when used in positron emission tomography (PET).