Search

Your search keyword '"Mukhametshina, Alsu R."' showing total 12 results
Start Over Author "Mukhametshina, Alsu R."
12 results on '"Mukhametshina, Alsu R."'

10. Targeted Nanoparticles for Selective Marking of Neuromuscular Junctions and ex VivoMonitoring of Endogenous Acetylcholine Hydrolysis

Author

Mukhametshina, Alsu R., Fedorenko, Svetlana V., Petrov, Alexey M., Zakyrjanova, Guzel F., Petrov, Konstantin A., Nurullin, Leniz F., Nizameev, Irek R., Mustafina, Asiya R., and Sinyashin, Oleg G.

Abstract

The present work for the first time introduces nanosensors for luminescent monitoring of acetylcholinesterase (AChE)-catalyzed hydrolysis of endogenous acetylcholine (ACh) released in neuromuscular junctions of isolated muscles. The sensing function results from the quenching of Tb(III)-centered luminescence due to proton-induced degradation of luminescent Tb(III) complexes doped into silica nanoparticles (SNs, 23 nm), when acetic acid is produced from the enzymatic hydrolysis of ACh. The targeting of the silica nanoparticles by α-bungarotoxin was used for selective staining of the synaptic space in the isolated muscles by the nanosensors. The targeting procedure was optimized for the high sensing sensitivity. The measuring of the Tb(III)-centered luminescence intensity of the targeted SNs by fluorescent microscopy enables us to sense a release of endogenous ACh in neuromuscular junctions of the isolated muscles under their stimulation by a high-frequency train (20 Hz, for 3 min). The ability of the targeted SNs to sense an inhibiting effect of paraoxon on enzymatic activity of AChE in ex vivoconditions provides a way of mimicking external stimuli effects on enzymatic processes in the isolated muscles.

Published
2018
Full Text
View/download PDF

11. Tb(III)-Doped Silica Nanoparticles for Sensing: Effectof Interfacial Interactions on Substrate-Induced Luminescent Response.

Author

Mukhametshina, Alsu R., Mustafina, Asiya R., Davydov, Nikolay A., Fedorenko, Svetlana V., Nizameev, Irek R., Kadirov, Marsil K., Gorbatchuk, Valery V., and Konovalov, Alexander I.

Subjects
*TERBIUM, *SILICA nanoparticles, *METAL ions, *DOPING agents (Chemistry), *CHEMICAL detectors, *SUBSTRATES (Materials science), *LUMINESCENCE spectroscopy
Abstract

The present work introduces the easymodification of the water-in-oilmicroemulsion procedure aimed at the doping of the Tb(III) complexeswithin core or shell zones of the silica nanoparticles (SNs), whichare designated as “core-shell”, “shell”,and “core”. The dye molecules, chelating ligands, andcopper ions were applied as the quenchers of Tb(III)-centered luminescencethrough dynamic or/and static mechanisms. The binding of the quenchersat the silica/water interface results in the quenching of the Tb(III)complexes within SNs, which, in turn, is greatly dependent on thesynthetic procedure. The luminescence of “core” SNsremains unchanged under the binding of the quenchers at the silica/waterinterface. The quenching through dynamic mechanism is more significantfor “core–shell” and “shell” thanfor “core” SNs. Thus, both “core–shell”and “shell” SNs have enough percentage of the Tb(III)complexes located close to the interface for efficient quenching throughthe energy transfer. The quenching through the ion or ligand exchangeis most efficient for “core–shell” SNs due tothe greatest percentage of the Tb(III) complexes at the silica/waterinterface, which correlates with the used synthetic procedure. Thehighlighted regularities introduce the applicability of “core–shell”SNs used as silica beads for phosphatidylcholine bilayers in sensingtheir permeability toward the quenching ions. [ABSTRACT FROM AUTHOR]

Published
2015
Full Text
View/download PDF

12. Silica Nanospheres Coated by Ultrasmall Ag0 Nanoparticles for Oxidative Catalytic Application

Author

Svetlana V. Fedorenko, Michail E. Jilkin, Irek R. Nizameev, Raffaello Mazzaro, Elizaveta O. Iurko, Vittorio Morandi, Kirill V. Kholin, Asiya R. Mustafina, Alsu R. Mukhametshina, Yulia H. Budnikova, Alberto Vomiero, Tatyana V. Gryaznova, Olga D. Bochkova, Fedorenko, Svetlana V., Jilkin, Michail E., Gryaznova, Tatyana V., Iurko, Elizaveta O., Bochkova, Olga D., Mukhametshina, Alsu R., Nizameev, Irek R., Kholin, Kirill V., Mazzaro, Raffaello, Morandi, Vittorio, Vomiero, Alberto, Mustafina, Asiya R., and Budnikova, Yulia H.

Subjects
Materials science, Settore ING-IND/22 - Scienza e Tecnologia dei Materiali, Composite number, Inorganic chemistry, Nanoparticle, 02 engineering and technology, C-H phosphonation, 010402 general chemistry, Electrochemistry, 01 natural sciences, Silver nanoparticle, Catalysis, Nanomaterials, chemistry.chemical_compound, Immobilization, Colloid and Surface Chemistry, Metallic silver(0), Silica, Nanomaterials, catalysis, Ag0, Silver nanoparticles, Materials Chemistry, Physical and Theoretical Chemistry, Hydrogen peroxide, Deposition (law), Catalytic activity, Silica nanoparticles, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Surfaces, Coatings and Films, Chemical engineering, chemistry, 0210 nano-technology, Biotechnology
Abstract

The present work introduces optimal modifiсation of core-shell composite nanomaterial, where small (2–8 nm) Ag0 nanoparticles are deposited onto large (about 140 nm) silica spheres for application in oxidative catalysis. The size of Ag0 and density of its deposition onto silica spheres was modified by the post treatment of initially deposited Ag0 (about 30 nm) by hydrogen peroxide in specific conditions. The comparison of catalytic effect of the post-treated and initial SN-Ag0 in electrochemical phosphonation of benzo(thia)oxazoles by diethyl phosphite in oxidative conditions revealed the difference between the composite nanoparticles. In particular, the post-treated SNs-Ag0 nanoparticles exhibit efficient catalytic effect in oxidative conditions resulting in facile and green method for synthesis of phosphonated benzooxa(thia)zoles, while no catalytic effect is observed under the use of larger Ag0 nanoparticles deposited onto silica spheres. The use of Ag0-based nanomaterial in oxidative catalysis had been never demonstrated before.

Published
2017
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results