Urease catalyzes the hydrolysis of urea to ammonia and carbon dioxide. The ammonia (nitrogen (N) product of urease activity) is incorporated into organic compounds. Thus, urease is involved in N remobilization, as well as in primary N assimilation. Two urease isoforms have been described for soybean: the embryo-specific, encoded by the Eu1 gene, and the ubiquitous urease, encoded by Eu4. A thir...

Ultrathin films of Eu3+ doped Y2O3 were deposited onto alumina nanoparticles using a unique solution synthesis method. The surface structure, composition, and morphology of the thin films deposited were analysed using high resolution transmission electron microscopy (TEM) and high angle annular dark field scanning TEM imaging and energy dispersive x-ray measurements. The films deposited were ex...

Ca2+ regulates ryanodine receptor's (RyR) activity through an activating and an inhibiting Ca2+-binding site located on the cytoplasmic side of the RyR channel. Their altered sensitivity plays an important role in the pathology of malignant hyperthermia and heart failure. We used lanthanide ions (Ln3+) as probes to investigate the Ca2+ sensors of RyR, because they specifically bind to Ca2+-bind...

Rare earth-doped materials are successfully utilized as non-contact optical temperature sensors. Thermal sensing is usually based on the ratiometric technique between two separate emission lines originated from thermally-coupled levels. We study Gd2O3:Eu3+ 1 at.% and YAG: Eu3+ 4 phosphors luminescence thermometers in 298–473 K range using both conventional experimental Judd-Ofelt theoretical ap...

Polvos cerámicos de Sm2O3 dopados y mezclados con europio se obtuvieron a partir la formación cloruros samario través ruta sol-gel citrato. Este trabajo reporta influencia los iones en las propiedades estructurales luminiscentes cerámicas Sm2O3:Eu3+ (coordenadas CIE) variando el Eu3+ 10 50% mol. Las características químicas, morfológicas fueron establecidas por FTIR XRD, revelando presencia ban...

We describe a procedure for the simultaneous immunofluorometric assay of lutropin and follitropin in human serum, based on the use of monoclonal antibodies and of the fluorescent lanthanides Eu3+ and Tb3+. The alpha-chain-specific antibody was used as a common capture antibody on the surfaces of microtitration strips. The anti-beta-follitropin antibody was labeled with Tb3+, the anti-beta-lutro...

We describe a two-site "sandwich"-type time-resolved immunofluorometric assay for human insulin, based on use of two monoclonal antibodies with different specificities. The first antibody is immobilized on the surface of microtiter plate strip wells, the other is labeled with Eu3+. Serum samples can be assayed with one incubation step; two incubation steps are required when plasma samples are a...

We consider the electronic structure of, and magnetic exchange spin interactions between, nominally nonmagnetic Eu3+ ions 4f6, S=3, L=3, J=0 within the context of the rocksalt structure compounds EuN and EuP. Both compounds are ionic Eu3+; N3− and P3− semimetals similar to isovalent GdN. Treating the spin polarization within the 4f shell, and then averaging consistent with the J=0 configuration...

In the last decade, numerous Ln-bearing metal-organic frameworks (MOFs) have been reported for luminescence thermometry applications. Although Ln3+ composition is always thoroughly determined, this parameter never optimized to improve thermometric performances. Here, optimization of performances luminescent probes tackled by reporting a series mixed Eu3+–Tb3+ frameworks. The are accessed as fun...