Search results for "Divalent metal ions"
showing 5 items of 5 documents
Divalent metal ion buffers with low pH-sensitivity
1973
Es werden Puffersysteme fur divalente Metallionen beschrieben, die im Bereich von etwa pH 6–10 gegenuber den herkommlichen Metallpuffern eine bemerkenswert niedrige pH-Abhangigkeit der Metallionenkonzentration und der Pufferkapazitat zeigen. Die Puffersysteme bestehen aus einem starken Komplexbildner (vorzugsweise einer Polyaminocarbonsaure) und zwei verschiedenen, divalenten Metallionen, die bezuglich der Bindung durch den Komplexbildner in Konkurrenz stehen. Dasjenige Metallion, dessen Konzentration gepuffert werden soll, wird als Primarion bezeichnet. Das zweite Ion, das Sekundarion genannt wird, soll vom Komplexbildner mindestens um den Faktor 10–100 schwacher gebunden werden. Die Gesam…
Development of a biosensor for copper detection in aqueous solutions using an Anemonia sulcata recombinant GFP.
2014
Fluorescent proteins from marine organisms represent potential candidates for biosensor development. In this paper, we described the isolation of a native green fluorescent protein from Anemonia sulcata and the cloning and purification of its equivalent as a recombinant protein in Escherichia coli. Furthermore, the spectroscopic behaviours of the native and recombinant GFPs were investigated as a function of Cu2+, Cd2+, Pb 2+ and Ni2+ concentration. Our results suggest the high selectivity of both proteins at copper than the other metals and, for the recombinant protein, a great sensitivity at a very low concentration (0.1-1 μM). Moreover, starting from these data, using the combination of …
Pseudopeptidic ligands: exploring the self-assembly of isophthaloylbisglycine (H2IBG) and divalent metal ions.
2012
We present a systematic study of the complexation of the new pseudopeptidic ligand isophthaloylbisglycine (H(2)IBG) with divalent metal ions of varying ionic radius. This work represents the initial employment of H(2)IBG in the coordination chemistry of alkaline earth, 3d transition, Zn(II) and Cd(II) metal elements. Infrared, NMR, thermal, magnetic, adsorption and theoretical studies of these compounds are also discussed.
Coamplexation of mercury(II) compounds by crown ethers in organic media
1991
Complexes between crown ethers having ring sizes of 15–24 atoms and 5 to 8 oxygens with HgX2 species (X = Cl, I, CN, SCN) have been prepared and studied. Interactions of the substituents X bound to mercury with groups or fragments in the crown compound are essential in determining the characteristics and stability of the complexes formed. Complexes with crowns of 18C6 ring sizes are the most favourable except for HgX2 compounds for which the size of X is larger than the macrocycle ring, as is the case for X = CF3.
Transition metal ion induced hydrogelation by amino-terpyridine ligands
2014
Hydrogelation behavior of a new class of terpyridine based metallogelators are explored. The gelation and the gel morphology was found to be critically dependent on divalent metal ions, anions and on subtle structural changes on the gelator molecule.