Received February 4,198O SUMMARY Field dispersion profiles of the proton spin-lattice relaxation rate, ~1-1, in chloroplast suspensions show a local maximum near 20 MHz, probably due to bound Mn(I1); EDTA extraction eliminates, and MnC12 addition restores, the paramagnetic relaxivity. Since neither treatment affects water oxidation, the Mn(I1) site monitored appears to lie outside the water-spl...

Magnetic resonance imaging (MRI) is the leading imaging technique for disease diagnostics. MRI contrast agents facilitate MRI technique to obtain tissue-specific image with improved sensitivity and signal-to-noise ratio. However, the applications of current MRI contrast agents are hampered by their uncontrolled blood circulation time, low relaxivity, and low specificity. To address such need, I...

Two new GdEGTA (EGTA = ethylene glycol-bis(2-aminoethylether)-N,N,N',N'-tetraacetic acid) derivatives incorporating aromatic moieties into the oxoethylenic bridge have been prepared and characterised, their conjugates to HSA investigated and an unprecedented high relaxivity, close to that predicted by theory, interpreted in terms of the combined effect of restricted local rotation and fast rate...

We describe herein a novel type of monodisperse water-soluble magnetite nanoparticle coated with pheomelanin using an environmentally-friendly approach in aqueous medium. The results indicate superparamagnetic behaviour at room temperature and show improved negative contrast in T2-weighted MRI with a transverse relaxivity of 218 mM(-1) s(-1).

This article presents a facile strategy to combine Eu(3+) and Gd(3+) ions into coacervate core micelles in a controlled way with a statistical distribution of the ions. Consequently, the formed micelles show a high tunability between luminescence and relaxivity. These highly stable micelles present great potential for new materials, e.g. as bimodal imaging probes.

The present study demonstrates that highly water-dispersed graphene nanoribbons dispersed by carboxyphenylated substituents and conjugated to aquated Gd(3+) ions can serve as a high-performance contrast agent (CA) for applications in T1- and T2-weighted magnetic resonance imaging (MRI) with relaxivity (r1,2) values outperforming currently-available clinical CAs by up to 16 times for r1 and 21 t...

Novel -type cyclodextrin (CD) derivatives, , and , bearing 6, 7 and 8 bis(carboxymethyl)amino (iminodiacetic acid) groups, respectively, were prepared, and their complexation with Eu(iii), Tb(iii) and Gd(iii) ions was studied. Luminescence titrations and mass spectrometry showed formation of multimetal complexes ( 2 to 3, mainly 3 and exactly 4 metal ions), whereas luminescence lifetime measure...

We report the synthesis and characterization of the novel ligand H(5)EPTPA-C(16) ((hydroxymethylhexadecanoyl ester)ethylenepropylenetriaminepentaacetic acid). This ligand was designed to chelate the Gd(III) ion in a kinetically and thermodynamically stable way while ensuring an increased water exchange rate (kappa(ex)) on the Gd(III) complex owing to steric compression around the water-binding ...

PURPOSE This study is to demonstrate the nanoscale size effect of ferrimagnetic H-ferritin (M-HFn) nanoparticles on magnetic properties, relaxivity, enzyme mimetic activities, and application in magnetic resonance imaging (MRI) and immunohistochemical staining of cancer cells. MATERIALS AND METHODS M-HFn nanoparticles with different sizes of magnetite cores in the range of 2.7-5.3 nm were syn...

A novel bis-hydroxymethyl-substituted DTTA chelator N'-Bz-C(4,4')-(CH(2)OH)(2)-DTTA () and its DTPA analogue C(4,4')-(CH(2)OH)(2)-DTPA () were synthesized and characterized. A variable-temperature (1)H NMR spectroscopy study of the solution dynamics of their diamagnetic (La) and paramagnetic (Sm, Eu) Ln(3+) complexes showed them to be rigid when compared with analogous Ln(3+)-DTTA and Ln(3+)-DT...