EDHPA based contrast agents for MR imaging, apparatus and methods
US4746507A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 2, 1985 |
| Grant date | May 24, 1988 |
| Priority date | — |
| Expiry date | Apr 2, 2005 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61K49/06
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
Ethylene Diamine Hydroxy Phenylacetic Acid (EDHPA) type chelators strongly bind paramagnetic metal ions to provide excellent contrast agents for magnetic resonance (MR) imaging. The magnetic dipole generated by unpaired electrons within the paramagnetic (PM) atom, causes a local reduction in the bulk magnetic field of the MR system. The resulting shortening of the T1 (spin lattice) relaxation time in the hydrogen protons within the area of interest, causes an intense "free induction signal" and a corresponding modulation in the collected scanning data. The tissue of organ of interest appears on the MR display as a high intensity of white area. Background tissue is displayed as darker or lower intensity greys. Each member chelator EDHPA' of the EDHPA family of chelators, is a phenolic analog of EDTA, with variations in the para position radical (PR) of the phenol ring. Each EDHPA' chelator is formed by twin amino acid molecules (phenylalanine etc), which provide twin chelation units having three coordination points each for binding the paramagnetic metal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.