Search results for "Fluorescence"
showing 10 items of 2463 documents
Towards the elaboration of new gold-based optical theranostics.
2014
Four new red BODIPY–gold(I) theranostic compounds were synthesized. Some of them were vectorized by tethering a biovector (glucose or bombesin derivatives) to the metallic center. Their photophysical properties were studied. Additionally, their cytotoxicity was examined on different cancer cell lines and on a normal cell line, they were tracked in vitro by fluorescence detection, and their uptake was evaluated by ICP-MS measurements.
DHEA-Bodipy–a functional fluorescent DHEA analog for live cell imaging
2009
International audience; The androgen dehydroepiandrosterone (DHEA) has been reported to protect neuronal cells against dysfunction and apoptosis. Several signaling pathways involved in these effects have been described but little is known about the intracellular trafficking of DHEA. We describe design, synthesis and characterization of DHEA-Bodipy, a novel fluorescent DHEA analog. DHEA-Bodipy proved to be a functional DHEA derivative: DHEA-Bodipy (i) induced estrogen receptor α-mediated gene activation, (ii) protected PC12 rat pheochromocytoma cells against serum deprivation-induced apoptosis, and (iii) induced stress fibers and focal adhesion contacts in SH-SY5Y human neuroblastoma cells. …
Development of an Easily Bioconjugatable Water-Soluble Single-Photon Emission-Computed Tomography/Optical Imaging Bimodal Imaging Probe Based on the …
2021
A water-soluble fluorescent aza-BODIPY platform (Wazaby) was prepared and functionalized by a polyazamacrocycle agent and a bioconjugable arm. The resulting fluorescent derivative was characterized and bioconjugated onto a trastuzumab monoclonal antibody as a vector. After bioconjugation, the imaging agent appeared to be stable in serum (>72 h at 37 °C) and specifically labeled HER-2-positive breast tumors slices. The bioconjugate was radiolabeled with [111In] indium and studied in vivo. The developed monomolecular multimodal imaging probe (MOMIP) is water-soluble and chemically and photochemically stable, emits in the near infrared (NIR) region (734 nm in aqueous media), and displays a goo…
Cellular imaging using BODIPY-, pyrene- and phthalocyanine-based conjugates
2017
International audience; Fluorescent Probes aimed at absorbing in the blue/green region of the spectrum and emitting in the green/red have been synthesized (as the form of dyads-pentads), studied by spectrofluorimetry, and used for cellular imaging. The synthesis of phthalocyanine-pyrene 1 was achieved by cyclotetramerization of pyrenyldicyanobenzene, whereas phthalocyanine-BODIPY 2c was synthesized by Sonogashira coupling between tetraiodophthalocyanine and meso-alkynylBODIPY. The standard four-steps BODIPY synthesis was applied to the BODIPY-pyrene dyad 3 starting from pyrenecarbaldehyde and dimethylpyrrole. H-1, C-13, F-19, (BNMR)-B-11, ICP, MS, and UV/Vis spectroscopic analyses demonstra…
Synthesis and In Vitro Evaluation of a Photosensitizer-BODIPY Derivative for Potential Photodynamic Therapy Applications
2015
A new photosensitizer (1) based on the 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) scaffold has been synthesized. 1 is water soluble and showed an intense absorption band at 490 nm (e=77600 cm-1M-1) and an emission at 514 nm. In vitro toxicity of 1 in the presence of light and in darkness has been studied with HeLa, HaCaT, MCF-7, and SCC-13 cell lines. Moreover, internalization studies of 1 in these cell lines were also performed. These results suggested that 1 is more toxic for SCC-13 and HeLa carcinoma cells than for the HaCaT noncancerous immortal human keratinocytes. Toxicity upon light irradiation was due to the formation of singlet oxygen and reactive oxygen species (ROS). Cel…
3-D image analysis of fluorescent drug binding
2004
Fluorescent ligands provide the means of studying receptors in whole tissues using confocal laser scanning microscopy and have advantages over antibody- or non-fluorescence-based method. Confocal microscopy provides large volumes of images to be measured. Histogram analysis of 3-D image volumes is proposed as a method of graphically displaying large amounts of volumetric image data to be quickly analyzed and compared. The fluorescent ligand BODIPY FL-prazosin (QAPB) was used in mouse aorta. Histogram analysis reports the amount of ligand-receptor binding under different conditions and the technique is sensitive enough to detect changes in receptor availability after antagonist incubation or…
Synthesis and fluorescence emission of neutral and anionic di- and tetra-carboranyl compounds
2011
A new family of photoluminescent neutral and anionic di-carboranyl and tetra-carboranyl derivatives have been synthesized and characterized. The reaction of α,α'-bis(3,5-bis(bromomethyl)phenoxy-m-xylene with 4 equiv. of the monolithium salt of 1-Ph-1,2-C(2)B(10)H(11) or 1-Me-1,2-C(2)B(10)H(11) gives the neutral tetracarboranyl-functionalized aryl ether derivatives closo-1 and closo-2, respectively. The addition of the monolithium salt of 1-Ph-1,2-closo-C(2)B(10)H(11) to α,α,'-dibromo-m-xylene or 2,6-dibromomethyl-pyridine gives the corresponding di-carboranyl derivatives closo-3 and closo-4. These compounds, which contain four or two closo clusters, were degraded using the classical method,…
Synthesis and Photodynamics of Fluorescent Blue BODIPY-Porphyrin Tweezers Linked by Triazole Rings
2012
Novel zinc porphyrin tweezers in which two zinc porphyrins were connected with π-conjugated boron dipyrromethenes (BDP meso-Por(2) and BDP β-Por(2)) through triazole rings were synthesized to investigate the photoinduced energy transfer and electron transfer. The UV-vis spectrum of BDP β-Por(2) which has less bulky substituents than BDP meso-Por(2) exhibits splitting of the Soret band as a result of the interaction between porphyrins of BDP β-Por(2) in the excited state. Such interaction between porphyrins of both BDP β-Por(2) and BDP meso-Por(2) is dominant at room temperature, while the coordination of the nitrogen atoms of the triazole rings to the zinc ions of the porphyrins occurs at l…
A Rapid and Sensitive Strip-Based Quick Test for Nerve Agents Tabun, Sarin, and Soman Using BODIPY-Modified Silica Materials
2016
Test strips that in combination with a portable fluorescence reader or digital camera can rapidly and selectively detect chemical warfare agents (CWAs) such as Tabun (GA), Sarin (GB), and Soman (GD) and their simulants in the gas phase have been developed. The strips contain spots of a hybrid indicator material consisting of a fluorescent BODIPY indicator covalently anchored into the channels of mesoporous SBA silica microparticles. The fluorescence quenching response allows the sensitive detection of CWAs in the mu g m(-3) range in a few seconds.
Near-infrared emitting fluorescent homobimetallic gold(I) complexes displaying promising in vitro and in vivo therapeutic properties
2021
International audience; Boron neutron capture therapy (BNCT) has the potential to specifically destroy tumor cells without damaging the tissues infiltrated by the tumor. BNCT is a binary treatment method based on the combination of two agents that have no effect when applied individually: 10B and thermal neutrons. Exclusively, the combination of both produces an effect, whose extent depends on the amount of 10B in the tumor but also on the organs at risk. It is not yet possible to determine the 10B concentration in a specific tissue using non-invasive methods. At present, it is only possible to measure the 10B concentration in blood and to estimate the boron concentration in tissues based o…