Effect of novel porphyrazine photosensitizers on normal and tumor brain cells

Photodynamic therapy (PDT) is a clinically approved procedure for targeting tumor cells. Though several different photosensitizers have been developed, there is still much demand for novel photosensitizers with improved properties. In this study we aim to characterize the accumulation, localization and dark cytotoxicity of the novel photosensitizers developed in-house derivatives of porphyrazines (pz I-IV) in primary murine neuronal cells, as well as to identify the concentrations at which pz still effectively induces death in glioma cells yet is nontoxic to nontransformed cells. The study shows that incubation of primary neuronal and glioma cells with pz I-IV leads to their accumulation in both types of cells, but their rates of internalization, subcellular localization and dark toxicity differ significantly. Pz II was the most promising photosensitizer. It efficiently killed glioma cells while remaining nontoxic to primary neuronal cells. This opens up the possibility of evaluating pz II for experimental PDT for glioma

Organosilicon Amidophosphates and Their Eu and Er Complexes in Solutions and Films: Spectral and Luminescence Properties

International audienceFluorescence and fluorescence excitation spectra of phosphorus-containing organosilicon ligands O = PX2NHR (X = NMe2, OPh; R = CH2CH2CH2Si(Oet)3 and their Eu(III) complexes in acetonitrile solutions and in films are studied. In UV region (285–420 nm), bis(dimethylamido)triethoxysilylpropylamidophosphate (X = NMe2) and diphenyltriethoxysilylpropylamidophosphate (X = OPh) exhibit two emission bands, whose position and intensity depend on the nature of substituents at the phosphorus atom. The Eu complexes show the ligand and the cation luminescence. The emission bands of coordinated ligands are shifted to long-wave region. The cation luminescence appears as three or four bands due to f-f transitions from the excited 5 D 0 level to the lower 7 F 1–4 levels. The most intense transition is 5 D 0 → 7 F 2. The emission band in a region of 420 nm appears in solutions and films prepared from both pure ligands and their Eu(III) complexes. This band is due to luminescence of spatially crosslinked nanoparticles of sesquioxane structure. The intensity ratio of the Eu3+ emission bands changes when going from solutions to films, the emission intensity increases in a range of 420 nm. Films containing incorporated Er complexes with amidophosphates show intense luminescence of a matrix at 430 nm and a series of weak narrow bands due to the Er3+ cation at 550–700 nm

Novel highly emissive tetracyanotetraphenylporphyrazine ytterbium complex for optoelectronic and biophotonic applications.

International audienceThe prepn. is described of a novel highly emissive ytterbium complex with a proposed unusual structure obtained by reaction of tricyanovinylbenzene (TCNVB) with bis(indenyl)ytterbium(II) in THF. The reaction occurs under extremely mild conditions, the tetraphenyltetracyanoporphyrazine macrocycle being assembled in high yield from TCNVB building-blocks by Yb3+-template synthesis. The anal., spectral and electrochem. investigations of the obtained ytterbium complex indicate its existence in the form of a binuclear adduct with Yb(TCNVB)3 species in which a one doubly reduced TCNVB mol. bridges two Yb3+ cations. The formation of a disordered polynuclear coordination polymer network including a macrocyclic structure and metal cations bridged through the nitrile nitrogen atoms is proposed. The complex is readily sol. and is compatible with a variety of polymeric matrixes giving doped polymeric glasses and films which are highly luminescent in the biol. relevant optical window covering the visible and near IR range (640-1000 nm). In addn., doped polymeric glasses and films highly emissive at the telecommunication wavelength (1540 nm) including the novel ytterbium complex and originally not luminescent erbium chelate in an equimolar ratio have been obtained. The compd. is found to be an extraordinarily strong sensitizer of near-IR Er3+ emission. Use of the Yb complex as a fluorescent marker for biomedical in vitro investigations has been demonstrate

Novel PEG-organized biocompatible fluorescent nanoparticles doped with an ytterbium cyanoporphyrazine complex for biophotonic applications

International audienceThe preparation and properties are described of two types of novel PEG-organized nanoparticles including silica-modified uniform disk-shaped nanoparticles doped with a fluorescent ytterbium cyanoporphyrazine complex; a large enhancement of red emission for both types of nanoparticles is observed in physiological liquids owing to their binding to biomolecule

Reaction of Sodium with Phenyltrichlorosilane

Original Russian Text: V.V. Semenov, A.Yu. Nerovnya, V.A. Egorov, N.F. Cherepennikova, L.G. Klapshina, A.I. Kirillov, T.I. Lopatina, W.E. Douglas, G.A. Domrachev, 2006, published in Doklady Akademii Nauk, 2006, Vol. 407, No. 4, pp. 489–492.International audienc

Preparation of luminescent sol–gel films from europium and terbium 3-(3'-triethoxysilylpropyl)pentane-2,4-dione complexes

International audienceTransparent luminescent sol–gel films have been prepared from the complexes of Eu and Tb with the new ligand 3-(3'-tri- ethoxysilylpropyl)pentane-2,4-dione synthesised by the reaction of 3-allylpentane-2,4-dione with triethoxysilane in the presence of Speier catalyst

Novel Tetraaryltetracyanoporphyrazine Vanadyl Complexes with Enhanced Electron Withdrawing Properties

International audienc

Organometallic self-organized nanomaterials for nonlinear optics

International audienceNovel nonlinear optical polymeric film-producing nanocomposites based on bis(arene)chromium complexes incorporated into a CN-containing matrix have been developed. Polymer-precursors were prepared by the reaction of Cr(EtnC6H6?n)2 mixtures (n = 1,2,3) with CN-containing vinyl monomers (acrylonitrile, crotononitrile and ethylcyanoacrylate). The nonlinear-optical measurements in the absence of external electrical fields showed a "natural" anisotropy resulting from self-organization taking place during the film formation process. Measurements by the spectrally-resolved two-beam coupling method confirmed that the test composites exhibited a significant cubic nonlinear optical susceptibility of the ultra-fast electronic type

Efficient Luminescent Solar Concentrators Based on Defectless Organic Glasses Containing Novel Ytterbium Cyanoporphyrazine Complex

International audienceA photocurable polymeric luminescent composition doped by a new ytterbium tetra(4 fluorophe nyl)tetracyanoporphyrazine complex capable of efficiently absorbing and reemitting light in a wide spectral range is developed. Defect free organic glasses obtained with the use of this composition were applied as waveguides in the creation of laboratory models of a luminescent solar concentrator. Tests results of the cre ated models showed the possibility of creating a stationary solar energy concentrator for photovoltaic cells (PVCs) which is at least as efficient as the best kinds of similar devices previously found worldwide