Europium-151 and iron-57 nuclear resonant vibrational spectroscopy of naturally abundant KEu(III)Fe(II)(CN) and Eu(III)Fe(III)(CN) complexes.

We have performed and analyzed the first combined Eu and Fe nuclear resonant vibrational spectroscopy (NRVS) for naturally abundant KEu(III)[Fe(II)(CN)] and Eu(III)[Fe(III)(CN)] complexes. Comparison of the observed Eu Fe NRVS spectroscopic features confirms that Eu(III) in both KEu(III)[Fe(II)(CN)] and Eu(III)[Fe(III)(CN)] occupies a position outside the [Fe(CN)] core and coordinates to the N atoms of the CN ions, whereas Fe(III) or Fe(II) occupies the site inside the [Fe(CN)] core and coordinates to the C atoms of the CN ions. In addition to the spectroscopic interest, the results from this study provide invaluable insights for the design and evaluation of the nanoparticles of such complexes as potential cellular contrast agents for their use in magnetic resonance imaging.

Light-responsive and Protic Ruthenium Compounds Bearing Bathophenanthroline and Dihydroxybipyridine Ligands Achieve Nanomolar Toxicity towards Breast Cancer Cells.

We report new ruthenium complexes bearing the lipophilic bathophenanthroline (BPhen) ligand and dihydroxybipyridine (dhbp) ligands which differ in the placement of the OH groups ([(BPhen) Ru(n,n'-dhbp)]Cl with n = 6 and 4 in 1 and 2 , respectively). Full characterization data are reported for 1 and 2 and single crystal X-ray diffraction for 1 . Both 1 and 2 are diprotic acids.

X-ray structure of chromium(III)-containing transferrin: First structure of a physiological Cr(III)-binding protein.

Transferrin, the Fe(III) transport protein in mammalian blood, has been suggested to also serve as a Cr(III) transporter and as part of a Cr(III) detoxification system; however, the structure of the metal-binding sites has never been fully elucidated with bound Cr(III). Chromium(III)-transferrin was crystallized in the presence of the synergistic anion malonate. In the crystals, the protein exists with a closed C-terminal lobe containing a Cr(III) ion and an open, unoccupied N-terminal lobe.