To understand the key determinants in calcium-binding affinity, a calcium-binding site with pentagonal bipyramid geometry was designed into a non-calcium-binding protein, domain 1 of CD2. This metal-binding protein has five mutations with a net charge in the coordination sphere of -5 and is termed DEEEE. Fluorescence resonance energy transfer was used to determine the metal-binding affinity of ...

Apart from the generally dominant trivalent oxidation state, several lanthanides can occur in divalent or tetravalent states as well. Changing valence state alters chemical properties and, therefore, gives opportunity to ease intragroup lanthanide separations. The hydrated terbium(III) ion has a highly positive reduction potential (E0 = + 3.1 V vs. SHE), but it be oxidized its via ozonolysis el...

     A simple, rapid, selective and highly sensitive fluorimetric method for determination of two catecholamines, i.e. norepinephrine (NE) and epinephrine (EP), in serum samples was developed. The method is based on the fluorescence sensitization of terbium (Tb3+) by complexation with both catecholamines in the presence of lanthanum (La3+), as a co-cation, and in a Na...

The extraction of Terbium (III)from aqueous nitrate solutions with a supported liquid membrane was investigated using a mixture of di-(2-ethylhexyl phosphoric acid (D2EHPA) and tri-octyl phosphine oxide (TOPO) with a molar ratio 1/0.4. The Hydrophobic Polyvinylidene Fluoride (PVDF) membrane was used as solid support. The sorption process followed pseudo-second-o...

A new terbium 2-isopropylimidazole-4,5-dicarboxylic acid complex was prepared and incorporated into titanium dioxide matrix by mild sol-gel method. Then we fabricated a terbium luminescent hybrid material, which displayed striking green emission even in pure water. It was interesting to find that this target material exhibited highly selective and fast (1 s) quenching effect to F(-) compared wi...

A novel time-resolved luminescence biosensor assay for anaplastic lymphoma kinase (ALK) was developed. We used a straightforward strategy to modify a known ALK substrate into a peptide biosensor that can accommodate terbium luminescence sensitization upon its phosphorylation by ALK. Since this strategy is generalizable, this high-throughput screening compatible assay serves as an example for de...

Fluorescence analysis is a simple and highly sensitive method for detection of small amounts biologically active substances. In this study, complexation terbium(III) chelates with 1,10-phenanthroline ascorbic acid (AA) luminescent properties complexes were investigated. The influence pH solubilization by micellar solutions nonionic, cationic, anionic surfactants on fluorescence was studied. que...

clinical asthma and airway responsiveness appear to be less severe when diabetes is superimposed. the aim of the present study was to determine the possible role of nitric oxide (no) in the airway reactivity under diabetic and diabetic-allergic conditions. twenty-five male guinea-pigs were divided into five groups of five each as follows: diabetic, antigen sensitized, diabetic- antigen sensitiz...

A highly sensitive fiber optic current sensor using terbium doped fiber is presented. The Verdet constant of the terbium doped fiber at 1300nm is found to be 19.5μrad/A using both a polarimetric and interferometric type sensor. Measurements on a Sagnac-loop sensor using 10cm of terbium doped fiber placed inside a solenoid show over 40dB of open loop dynamic range as well as a minimum detectable...