Particulate NMR contrast agents for gastrointestinal application
AssigneeVanderbilt University
InventorsVal M. Runge, Jeffrey A. Clanton
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Abstract
Contrast media compositions for nuclear magnetic resonance (NMR) imaging of the gastrointestinal system are provided for oral or rectal administration. The compositions comprise aqueous suspensions of particles of an NMR contrast agent, the particles being very finely-divided and providing in their outer surfaces a substantially water-insoluble paramagnetic compound. Suspending and/or wetting agents may be included to maintain the contrast agent particles in a dispersed, suspended condition for the oral or rectal administration. Buffering agents may also be included to maintain the pH of the suspension in a pH range protecting the insolubility of the paramagnetic compound.
Claims12
A contrast medium composition for nuclear magnetic resonance (NMR) imaging of the gastrointestinal system, comprising an orally or rectally administrable aqueous suspension of particles of an NMR contrast agent said suspension containing wetting and/or suspending agents to maintain said contrast agent particles in a dispersed suspended condition, said particles comprising a substantially water-insoluble compound of a paramagnetic metal, said particles being sized below 10 microns diameter and being capable of passing through the stomach while remaining in particulate form.
A contrast medium composition for nuclear magnetic resonance (NMR) imaging of the gastrointestinal system, comprising an orally or rectally administrable aqueous suspension of particles of an NMR contrast agent, said suspension containing of wetting and/or suspending agents to maintain said contrast agent particles in a dispersed suspended condition for the administration, said particles being sized in the range below 3 microns diameter and being composed of a compound of a paramagnetic metal, said particles being insoluble to the extent that less than 1% by weight dissolves in 30 minutes at a temperature of 37.degree. C. in water adjusted to a pH of 1.2 with hydrochloric acid so that said particles are capable of passing through the stomach in particulate form.
A contrast medium composition for nuclear magnetic resonance (NMR) imaging of the gastrointestinal system, comprising an orally or rectally adminstrable aqueous suspension of finely-divided particles of an NRM contrast agent, said suspension containing wetting and/or suspending agents to maintain said contrast agent particles in a dispersed suspended condition for the administration, said suspension also containing a buffering agent for maintaining the pH of the suspension in a pH range of 6.0 to 8.5 for protecting the insolubility of the contrast agent, said particles being sized below 3 microns diameter and being composed of a compound of a paramagnetic metal, said particles being insoluble in the suspension to the extent that less than 1% by weight dissolves in 30 minutes at a temperature of 37.degree. C. so that said particles are capable of passing through the stomach in particulate form.
Dependencies are inferred from the claim text.