Search results for "Fluorescence"
showing 10 items of 2463 documents
Water-Soluble Aza-BODIPYs: Biocompatible Organic Dyes for High Contrast In Vivo NIR-II Imaging
2020
International audience; A simple NIR-II emitting water-soluble system has been developed and applied in vitro and in vivo. In vitro, the fluorophore quickly accumulated in 2D and 3D cell cultures and rapidly reached the tumor in rodents, showing high NIR-II contrast for up to 1 week. This very efficient probe possesses all the qualities necessary for translation to the clinic as well as for the development of NIR-II emitting materials.
Magnetic–fluorescent Langmuir–Blodgett films of fluorophore-labeled ferritin nanoparticles
2009
Abstract We have covalently coupled fluorophore 4-(2-hydroxyethoxy)-7-nitro-2,1,3-benzoxadiazole (NBD) to the external ferritin shell through lysine residues. An increase in the luminescence quantum yield of the fluorescent ferritin particles and a blue shift in its emission peak compared to individual fluorophore were observed. The study of the particles by transmission electron microscopy showed that the native iron core ferritin is intact and that no degradation occurs during chemical functionalization of the protein shell. The NBD-labeled ferritin particles are water soluble, which allowed their controlled deposition by the Langmuir–Blodgett (LB) technique. Superparamagnetic and fluores…
Ceria/polymer nanocontainers for high-performance encapsulation of fluorophores
2019
We report the synthesis of high-performance organic–inorganic hybrid fluorescent nanocapsules comprising a polymer shell armored with an inorganic layer and a liquid core containing a fluorophore. The polymeric capsules are synthesized by free radical miniemulsion polymerization and contain covalently bound carboxylate surface functionalities that allow for the binding of metal ions through electrostatic interaction. A cerium(IV) oxide nanoparticle layer, formed in situ at the surface of the hybrid nanocapsules, acts as oxygen scavenger and keeps external reactive molecular oxygen from entering into the capsules, eventually resulting in a reduction of the photooxidation of encapsulated fluo…
Development of Trackable Anticancer Agents Based on Metal Complexes
2016
Abstract The design of trackable anticancer agents is of major interest for the future development of therapeutics based on nonplatinum metal complexes such as Ru(II), Os(II), or Au(I) derivatives, and more particularly for the understanding of the mechanism of action of these metal-based drugs. This review reports the synthesis and the first biological studies of original trackable complexes, in which the metal complex was coupled to an imaging probe, such as a fluorophore (coumarin, borodipyrromethene derivative (BODIPY), porphyrin), or a chelating agent (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA)) for radioisotopic imaging PET (positron emission tomography) or SPECT …
Gold(I)-Coumarin-Caffeine-Based Complexes as New Potential Anti-Inflammatory and Anticancer Trackable Agents.
2018
Three new gold(I)-coumarin-based trackable therapeutic complexes and two non-trackable analogues have been synthesised and fully characterised. They all display anti-proliferative properties on several types of cancer cell lines, including those of colon, breast, and prostate. Two complexes displayed significant anti-inflammatory effects; one displayed pro-inflammatory behaviour; this highlights the impact of the position of the fluorophore on the caffeine scaffold. Additionally, the three coumarin derivatives could be visualised in vitro by two-photon microscopy.
Fluorometric determination of chemically available lysine: adaptation, validation and application to different milk products.
2004
A spectrophotometric method based on the reaction between available lysine and ortho-phthaldialdehyde (OPA) was adapted and validated for fluorometric determination of the chemically available lysine contents in milk matrices (UHT and conventional in-bottle sterilized cow milk, milk-based infant formulas and infant formula ingredients). The values of the analytical parameters show its usefulness as a routine method (linearity, r = 0.9992; detection limit, 0.0066 mg/mL assay; accuracy, 99-108%; precision, intra-day 2.1-5.9% and inter-day 3.5 10.2%). No statistically significant differences (p < 0.05) were found between the values obtained with the adapted method and those obtained applying t…
Exploring the spatial relationship between airborne-derived red and far-red sun-induced fluorescence and process-based GPP estimates in a forest ecos…
2019
International audience; Terrestrial gross primary productivity (GPP) plays an essential role in the global carbon cycle, but the quantification of the spatial and temporal variations in photosynthesis is still largely uncertain. Our work aimed to investigate the potential of remote sensing to provide new insights into plant photosynthesis at a fine spatial resolution. This goal was achieved by exploiting high-resolution images acquired with the FLuorescence EXplorer (FLEX) airborne demonstrator HyPlant. The sensor was flown over a mixed forest, and the images collected were elaborated to obtain two independent indicators of plant photosynthesis. First, maps of sun-induced chlorophyll fluore…
Electric Field Dependence of the Fluorescence Intensity of Solute Molecules and Fourth Order Effects
1985
Abstract The effect of an external electric field on the total fluorescence of solute molecules is studied up to fourth order theoretically, and is checked experimentally with 4´-N,N-dimethylamino- 4-nitrostilbene in dioxane at room temperature.
Core hole screening and decay rates of double core ionized first row hydrides.
2013
Because of the high intensity, X-ray free electron lasers allow one to create and probe double core ionized states in molecules. The decay of these multiple core ionized states crucially determines the evolution of radiation damage in single molecule diffractive imaging experiments. Here we have studied the Auger decay in hydrides of first row elements after single and double core ionization by quantum mechanical ab initio calculations. In our approach the continuum wave function of the emitted Auger electron is expanded into spherical harmonics on a radial grid. The obtained decay rates of double K-shell vacancies were found to be systematically larger than those for the respective single …
Immuno-fluorescence cytochemistry on thin frozen sections of human substantia nigra for staining of monoamine oxidase A and monoamine oxidase B: a pi…
1990
Immunofluorescence cytochemistry on thin frozen sections of human substantia nigra for staining of MAO-A and MAO-B revealed that only about 10% of the melanin-containing neurons are positive for MAO-A, while they are substantially free of MAO-B.