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В журнале International Journal of Molecular Sciences   (IF=4,556) опубликована статья  с участием сотрудников Института: чл.-корр. РАН, проф. д.х.н. Н.Ф. Салахутдинова (зав.отделом ЛФАВ), проф. РАН, д.х.н. К. П. Волчо (гнс, ЛФАВ),  к.х.н. Т. М. Хоменко (снс, ЛФАВ)


Alterations of STEP46 and STEP61 Expression in the Rat Retina with Age and AMD-Like Retinopathy Development

Darya V. Telegina, Elizabeth A. Kulikova, Oyuna S. Kozhevnikova, Alexander V. Kulikov, Tatyana M. Khomenko, Konstantin P. Volcho, Nariman F. Salakhutdinov and Nataliya G. Kolosova



Int. J. Mol. Sci. 202021(15), 5182
Publication Date:July 22, 2020


 https://doi.org/10.3390/ijms21155182

 (This article belongs to the Special Issue Molecular Biology of Age-Related Macular Degeneration (AMD) 2.0)

Abstract

Tyrosine phosphatase STEP (striatal-enriched tyrosine protein phosphatase) is a brain-specific protein phosphatase and is involved in the pathogenesis of many neurodegenerative diseases. Here, we examined the impact of STEP on the development of age-related macular degeneration (AMD)-like pathology in senescence-accelerated OXYS rats. Using OXYS and Wistar rats (control), we for the first time demonstrated age-dependent changes in Ptpn5 mRNA expression, STEP46 and STEP61 protein levels, and their phosphatase activity in the retina. The increases in STEP protein levels and the decrease of total and STEP phosphatase activities in the retina (as compared with Wistar rats) preceded the manifestation of clinical signs of AMD in OXYS rats (age 20 days). There were no differences in these retinal parameters between 13-month-old Wistar rats and OXYS rats with pronounced signs of AMD. Inhibition of STEP with TC-2153 during progressive AMD-like retinopathy (from 9 to 13 months of age) reduced the thickness of the retinal inner nuclear layer, as evidenced by a decreased amount of parvalbumin-positive amacrine neurons. Prolonged treatment with TC-2153 had no effect on Ptpn5 mRNA expression, STEP46 and STEP61 protein levels, and their phosphatase activity in the OXYS retina. Thus, TC-2153 may negatively affect the retina through mechanisms unrelated to STEP. View Full-Text

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В журнале The Journal of Physical Chemistry Letters   (IF=6,71) опубликована статья  с участием сотрудников Института к.х.н. О.И. Рогожниковой (с.н.с, ГИТР), Д.В. Трухина (снс, ГИТР),  к.х.н. А.А. Кужелева (нс, ЛОЭ), д.ф.-м.н., проф. Е.Г. Багрянской (Директор НИОХ), к.х.н. В.М. Тормышева (снс, рук. группы ГИТР)


Multiquantum Counting of Trityl Radicals

Matthias Bretschneider, Phillip E. Spindler, Olga Yu. Rogozhnikova, Dmitry V. Trukhin, Burkhard Endeward, Andrey A. Kuzhelev, Elena Bagryanskaya, Victor M. Tormyshev, and Thomas F. Prisner



J. Phys. Chem. Lett. 2020, 11, 15, 6286–6290
Publication Date:July 15, 2020


 https://doi.org/10.1021/acs.jpclett.0c01615

 2020_07_28_PhChLett.gif

Abstract

We demonstrate a series of multitrityl radical compounds where accurate spin-counting by pulsed electron paramagnetic resonance (EPR) can be achieved at X-band (9 GHz) frequencies, even for molecules with very short and flexible linkers. Multiquantum filter experiments, well-known from NMR, were used to count the number of coupled electron spins in these compounds. The six pulse double quantum filter sequence used in EPR for distance determinations in biradicals was used. Precise phase settings to separate higher quantum coherences were achieved by an arbitrary waveform generator. The trityl radicals have narrow spectral width so that homogeneous excitation of all spins by the pulses is possible. The transversal relaxation times of higher quantum coherences of trityl radicals are sufficiently long to allow their detection. Our results on model compounds show the potential of this approach to determine oligomeric states in protein complexes in their native environment using functionalized trityl spin labels.

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В  журнале Crystal Growth & Design   (IF=4,089) опубликована статья  с участием сотрудников Института к.х.н. Е.А. Чулановой н.с, ЛГеТС), Е.А. Радюш (мнс, ЛОЭ),  к.х.н. И.К. Шундриной (снс, ЛЭАСМ), д.х.н. И.Ю. Багрянской (внс, рук. группы ГРСА), к.х.н. Н.А. Семёнова (снс, ЛГеТС) и д.х.н. А.В. Зибарева (завлаб, ЛГеТС) 


Lewis Ambiphilicity of 1,2,5-Chalcogenadiazoles for Crystal Engineering: Complexes with Crown Ethers

Elena A. Chulanova, Ekaterina A. Radiush, Inna K. Shundrina, Irina Yu. Bagryanskaya, Nikolay A. Semenov, Jens Beckmann, Nina P. Gritsan, and Andrey V. Zibarev



Cryst. Growth Des. 2020, 20, 9, 5868–5879
Publication Date:July 13, 2020


 https://doi.org/10.1021/acs.cgd.0c00536

 2020 07 29 CGD

Abstract

The cocrystallization of 1,2,5-chalcogenadiazoles (chalcogen E = S, Se, and Te) with cyclic polyethers 18-crown-6 (18-c-6) and dibenzo-18-crown-6 (db-18-c-6) yielded the molecular complexes characterized by X-ray diffraction and thermogravimetry/differential scanning calorimetry techniques together with density functional theory (DFT) calculations and quantum theory of atoms in molecule and natural bond orbitals analysis. The complexes are bound by multiple secondary bonding interactions, the most important of which reflects the Lewis ambiphilicity of 1,2,5-chalcogenadiazoles and includes charge transfer from O atoms of the ethers onto E atoms of the chalcogenadiazoles (i.e., chalcogen bonding), and the back-donation from E to O. For complexes of 18-c-6, the DFT-calculated energies of bonding interactions correlate with the melting temperatures of the complexes, as well as with the atomic number of E and the size of the E-associated σ-holes but not with the maximum of molecular electrostatic potential at the σ-holes. Taking into account the previous results, the Lewis ambiphilicity of 1,2,5-chalcogenadiazoles may be used for applications in crystal engineering.

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В журнале Applied Organometallic Chemistry   (IF=3,14) опубликована статья  с участием сотрудников Института д.х.н. И.И. Олейника (в.н.с, ЛЭАСМ) и  к.х.н. И.В. Олейник (с.н.с, ЛЭАСМ) 


Achieving strictly linear polyethylenes by the NNN‐Fe precatalysts finely tuned with different sizes of ortho‐cycloalkyl substituents

Hongyi Suo, Zilong Li, Irina V. Oleynik, Zheng Wang, Ivan I. Oleynik, Yanping Ma, Qingbin Liu, Wen‐Hua Sun



Applied Organometallic Chemistry 
Volume34, Issue11
November 2020, e5937


 https://doi.org/10.1002/aoc.5937

 

Abstract

Six examples of newly synthesized α,α’‐bis (aryl)‐2,3:5,6‐bis (pentame thylene)pyridyliron complexes [2,3:5,6‐{C4H8C(NAr)}2C5HN]FeCl2 (Ar = 2‐(c‐C5H9)‐6‐MeC6H3 Fe1 , 2‐(c‐C6H11)‐6‐MeC6H3 Fe2 , 2‐(c‐C8H15)‐6‐MeC6H3 Fe3 , 2‐(c‐C5H9)‐4,6‐Me2C6H2 Fe4 , 2‐(c‐C6H11)‐4,6‐Me2C6H2 Fe5 , 2‐(c‐C8H15)‐4,6‐Me2C6H2 Fe6 refers as cyclic), on activation with methylalumoxane (MAO) or modified MAO (MMAO), exhibit high activities towards ethylene polymerization, producing strictly linear polyethylenes with terminal vinyl groups. The catalytic performances are systematically investigated along with various polymerization parameters as well as the microstructures of resultant polyethylenes. The steric hindrances of ortho‐cycloalkyl substituents of Nimino‐aryl groups significantly affect the activities of the corresponding iron precatalysts as well as the microstructures of resultant polyethylenes: higher steric hindrance the ortho‐cycloalkyl substituents, higher activity the iron precatalyst, lower molecular weight the resultant polyethylenes. Experimental observations are additionally supported by the computational study. The resultant polyethylenes exhibited excellent hydrophobicity.

Funding Information

  • Bureau of International Cooperation of Chinese Academy of Sciences. Grant Numbers: 121111KYSB20190005, No. 121111KYSB20190005
  • Russian Foundation for Basic Research. Grant Numbers: 18‐53‐80031, No. 18‐53‐80031
  • Russian State funded budget project. Grant Numbers: 0302‐2019‐0007, No. 0302‐2019‐0007
  • National Natural Science Foundation of China. Grant Number: No. 21871275 and 51861145303

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В журнале Polymers   (IF=3,426) опубликован обзор  с участием  д.х.н., проф. Е.Г. Багрянской

 New Variants of Nitroxide Mediated Polymerization

Gérard Audran , Elena G. Bagryanskaya , Sylvain R. A. Marque and Pavel Postnikov

Polymers, 2020, 12 (7), 1481;

Published: 2 July 2020

https://doi.org/10.3390/polym12071481

2020_07_03_Polymers

 

Abstract

Nitroxide-mediated polymerization is now a mature technique, at 35 years of age. During this time, several variants have been developed: electron spin capture polymerization (ESCP), photoNMP (NMP2), chemically initiated NMP (CI-NMP), spin label NMP (SL-NMP), and plasmon-initiated NMP (PI-NMP). This mini-review is devoted to the features and applications of these variants. 
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Keywords: nitroxide mediated polymerizationCI-NMPSLNMPPI-NMPNMP2ESCP

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В журналк Dyes and Pigments (IF 4,018) опубликована статья с участием сотрудников
Института: к.х.н. А.Д. Куимова (мнс, ЛОЭ), к.х.н. К.С. Беккер (снс, ЛОЭ), И.Р. Коскина (мнс ЛОЭ), А.С. Сониной (нс, ЛОЭ), к.х.н. И.К. Шундриной (снс, ЛЭАСМ), к.х.н. М.С. Казанцева (зав.лаб, с.н.с ЛОЭ)

2-((9H-fluoren-9-ylidene)methyl)pyridine as a new functional block for aggregation induced emissive and stimuli-responsive materials

Anatoly D.Kuimov, Christina S.Becker, Igor P.Koskin, Daniiar E.Zhaguparov, Alina A.Sonina, Inna K.Shundrina, Peter S.Sherinb, Maxim S.Kazantsev

Dyes and Pigments, Volume 181, October 2020, 108595

First online: June 2, 2020


 https://doi.org/10.1016/j.dyepig.2020.108595

2020_06_01_obe_Vorobev_250

 

Abstract

Highly-emissive mechanofluorochromic (MFC) organic solids changing their emission colors upon exposure to mechanical stimuli are highly demanded for various practical applications. In this work we introduced a planarizable by intramolecular N⋯H bond 2-((9H-fluoren-9-ylidene)methyl)pyridine fragment featuring an Aggregation-Induced Emission Enhancement and, particularly, MFC property for its bithiophene derivative. A two compounds, 2-((9H-fluoren-9-ylidene)methyl)-5-(5-phenylthiophen-2-yl)pyridine (FTP) and 2-((9H-fluoren-9-ylidene)methyl)-5-([2,2′-bithiophen]-5-yl)pyridine (FTT) were synthesized and fully characterized. In liquid solution both compounds are low emissive, however in the solid state they exhibit the photoluminescence quantum yield of 33% and 13% for FTP and FTT, respectively. Remarkably, the powder of FTT demonstrates a self-reversible mechanofluorochromism: the emission spectrum red-shifts after the grinding or pressurization and it recovers during one-day of storage without any treatment. The powder X-ray diffraction and differential scanning calorimetry revealed the reversible phase transition under temperature and mechanic stimuli. Analysis of molecular structure shows that in the gas phase FTT has a planar geometry while in the solid state it loses the flatness due to the crystal environment. Our results speak in favor of the increase of FTT planarity under the pressure to be responsible for the observed mechanofluorochromism.

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В журнале Chemistry - A European Journal   (IF=5,16) опубликована статья  с участием сотрудника Института к.х.н. А.М. Агафонцева (с.н.с, ЛТС)

Ratiometric detection of ATP by fluorescent cyclophanes with bellows‐type sensing mechanism

Aleksandr M. Agafontsev, Tatiana A. Shumilova, Aleksandr S. Oshchepkov, Frank Hampel, Evgeny A Kataev

Chemistry - A European Journal, 

Volume 26 , Issue 44 Special Issue: Young Chemists 2020

August 6, 2020, Pages 9991-9997

YC IconThis article also appears in:
 


 https://doi.org/10.1002/chem.202001523


chem202001523 toc 0001 m

Abstract

Pyrene‐based cyclophanes have been synthesized with the aim to realize a bellows‐type sensing mechanism for the ratiometric detection of nucleotide concentrations in a buffered aqueous solution. The sensing mechanism involves the encapsulation of a nucleobase between two pyrene rings, which affects the monomer‐excimer equilibrium of the receptor in the excited state. The nature of the spacer and its connection pattern to pyrene rings have been varied to achieve high selectivity for ATP. The 1,8‐substituted pyrene‐based cyclophane with the 2,2′‐diaminodiethylamine spacer demonstrates the best selectivity for ATP showing a 50‐fold increase in the monomer‐excimer emission ratio upon saturation with the nucleotide. The receptor can detect ATP within the biological concentrations range over a wide pH range. NMR and spectroscopic studies have revealed the importance of hydrogen bonding and stacking interactions for achieving a required receptor selectivity. The probe has been successfully applied for the real‐time monitoring of creatine kinase activity.

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В журнале Biomedical Optics Express (IF 3,91) опубликована статья с участием сотрудника
Института: к.х.н. А.Ю. Воробьева (зав.лаб, с.н.с ЛФ)

Optical uncaging of ADP reveals the early calcium dynamics in single, freely moving platelets

Darya V. Spiryova, Alexei Yu. Vorobev, Vadim V. Klimontov, Elena A. Koroleva, and Alexander E. Moskalensky

Biomedical Optics Express Vol. 11, Issue 6, pp. 3319-3330 (2020)

Published: May 27, 2020


 https://doi.org/10.1364/BOE.392745

2020_06_01_obe_Vorobev_250

 

Abstract

Platelet activation is considered to be a cornerstone in pathogenesis of cardiovascular disease. The assessment of platelet activation at the single-cell level is a promising approach for the research of platelet function in physiological and pathological conditions. Previous studies used the immobilization of platelets on the surface, which significantly alters the activation signaling. Here we show that the use of photolabile “caged” analog of ADP allows one to track the very early stage of platelet activation in single, freely moving cells. In this approach, the diffusion step and ADP receptor ligation are separated in time, and a millisecond-timescale optical pulse may trigger the activation. The technique allows us to measure the delay (lag time) between the stimulus and calcium response in platelets. We also propose a simple model function for calcium peaks, which is in good agreement with the measured data. The proposed technique and model function can be used for in-depth studies of platelet physiology.

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В журнале Dalton Transactions (IF 4,052) опубликована статья с участием сотрудников Института   д.х.н., проф.  А.В. Ткачева (завлаб, ЛТС) и к.х.н. А.М. Агафонцева (снс, ЛТС):

Luminescent Zn(II) and Cd(II) complexes with chiral 2,2′-bipyridine ligands bearing natural monoterpene groups: synthesis, speciation in solution and photophysics

 2020_05_19_DT

Abstract

Mononuclear zinc(II) and cadmium(II) complexes, ZnLCl2 (1), CdLCl2 (2), ZnL1Cl2·2H2O (3), and CdL1Cl2·2H2O (4), with chiral ligands containing a 2,2′-bipyridine moiety and natural terpene (+)-limonene (L) or (+)-3-carene (L1) moieties were synthesized. In these complexes the L and L1 ligands are shown to coordinate Zn2+ and Cd2+ ions through the 2,2′-bipyridine moiety. The acetamide group of the ligands interacts with M2+ ions by forming N⋯M>2+> and C[double bond, length as m-dash]O⋯M2+contacts and N–H⋯Cl hydrogen bonds with coordinated Cl ions. In solutions the complexes have several conformers differing by the degree of the turn of the acetamide moiety relative to the ligand core and the type of its interaction with the coordination core. The ligands and complexes exhibit luminescence with the quantum yield increasing in the order: ligand < cadmium(II) complex < zinc(II) complex. The complexes 3 and 4 demostrate excitation wavelength independent single-channel fluorescence. As opposed to 3 and 4, the complexes 1 and 2 demonstrate excitation wavelength dependent emission with nanosecond and microsecond lifetimes of the excited states. According to our TD-DFT calculations, an interplay of ligand centered and halide to ligand transitions facilitates two deactivation channels in 1 and 2: S1–S0 and T1–S0.

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В журнале  Успехи химии/Russian Chemical Reviews  (IF 4.612) опубликован обзор сотрудников Института

Ю.А. Тена, к.х.н. Н.М. Трошковой и д.х.н. Е.В. Третьякова

От спин-меченых конденсированных полиароматических соединений к магнитно-активным графеновым наноструктурам

Ю.А. Тен, Н.М. Трошкова, Е.В. Третьяков

Успехи химии, 2020, Том 87, Номер 7, Страницы 693-712

From spin-labelled fused polyaromatic compounds to magnetically active graphene nanostructuresFrom spin-labelled fused polyaromatic compounds to magnetically active graphene nanostructures

Yu A Ten,  N M Troshkova, a E V Tretyakov

Russian Chemical Reviews, 2020, Volume 89, Number 7, Pages 693-712

 https://doi.org/10.1070/RCR4923

rc4923c.gif

 

Анотация

Молекулярный дизайн магнитно-активных графеновых наноструктур - формирующаяся область науки. Основная цель таких исследований - получение графеновых нанолент и графеновых квантовых точек с заданными электронными, оптическими и магнитными свойствами. В обзоре рассмотрены методы синтеза спин-меченых полициклических ароматических углеводородов - гомологических предшественников графеновых наноструктур. Обсуждены достижения и перспективы развития дизайна магнитно-активных графеновых материалов. Библиография - 134 ссылки.

Abstract

Molecular design of magnetically active graphene nanoscale structures is an emerging field of research. The key goal of this research is to produce graphene nanoribbons and graphene quantum dots with specified electronic, optical and magnetic properties. The review considers methods for the synthesis of spin-labelled polycyclic aromatic hydrocarbons, the homologous precursors of graphene nanostructures and discusses the achievements and prospects of the design of magnetically active graphene materials. Bibliography — 134 references

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10.1002/cctc.202000070




Hot Topic: Carbon, Graphite, and Graphene


2020_CCtC_Li-Zulanov

Just add water! A range of heterogeneous ‐SO3H functionalized catalysts were investigated for the first time using the Prins‐Ritter (−)‐isopulegol reaction with benzaldehyde and acetonitrile as a model producing 4‐amido derivatives of octahydro‐2H‐chromenes (as S‐ and R‐diastereomers). A strong effect of water addition prior the reaction on the overall selectivity and the ratio of isomers was found.

 


На сайте  журнала ChemCatChem (IF 4,495) опубликована статья с участием сотрудников Института:  Н.С. Ли-Жуланова (мнс, ЛНТПС),  д.х.н., проф. РАН К.П. Волчо (гнс, ЛФАФ) и д.х.н., член.-корр. РАН, поф. Н.Ф. Салахутдинова (зав .отделом медицинской химии)

Stereoselectivity Inversion by Water Addition in the −SO3H‐catalyzed Tandem Prins‐Ritter Reaction for Synthesis of 4‐amidotetrahydropyran Derivatives

Dr. Alexander Yu. Sidorenko,  Nikolai S. Li‐Zhulanov, Päivi Mäki‐Arvela, Thomas Sandberg, Anna V. Kravtsova, Andreia F. Peixoto, Cristina Freire, Konstantin P. Volcho, Nariman F. Salakhutdinov, Vladimir E. Agabekov, Prof. Dmitry Yu. Murzin


ChemCatChem, Volume12, Issue 9, May 7, 2020, Pages 2605-2609

First published: 05 Februaryr 2019

doi: 10.1002/cctc.202000070


 

Abstract

A range of heterogeneous ‐SO3H functionalized catalysts including carbon and halloysite nanotubes, commercial K10 clay, Amberlyst‐15 etc. was investigated for the first time using as a model the Prins‐Ritter reaction of (−)‐isopulegol with benzaldehyde and acetonitrile producing 4‐amido derivatives of octahydro‐2H‐chromenes (as (S)‐ and (R)‐diastereomers). A strong effect of water addition prior the reaction on the overall selectivity and the ratio of isomers in the case of heterogeneous and homogeneous (p‐toluenesulfonic acid) catalysis was found for the first time. The yield of the (R)‐diastereomer sharply increased with increasing amount of added water, while the S‐isomer prevailed with a minimum amount of added water. Experimental results and DFT calculations clearly indicate a kinetic control for R‐amide formation. Typically synthesis of 4‐amidooctahydro‐2H‐chromenes requires subzero temperatures and toxic catalysts, which were avoided in the current work. Nevertheless, the yield of the desired products (up to 83 %) at 30 °C after water addition exceeded the values reported previously. Thus, adding water is a simple and a very effective method for controlling both the yield and stereoselectivity of the Prins‐Ritter reaction products under mild conditions.

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В журналу Materials Science and Engineering: C  (IF 4,959) опубликована статья с участием сотрудников Института:  д.м.н. Н.А. Жуковой (внс, ЛФИ), д.б.н. М.В. Хвостова (снс, ЛФИ), к.б.н.А.В. Павловой (нс, ЛФИ) и д.б.н., проф. Т.Г. Толстиковой (завлаб, ЛФИ)

Biodegradable poly(l-lactide)/calcium phosphate composites with improved properties for orthopedics: Effect of filler and polymer crystallinity

 

Abstract

Biodegradable poly(l-lactide)/calcium phosphate composites are promising materials for fabrication of bone fixation implants with improved properties. Multistage compounding was proposed as an efficient method for the preparation of biodegradable poly(l-lactide)/calcium phosphate composites with submicron filler dispersion and mechanical characteristics similar to native bone. The improvement of the characteristics is caused both by the filler itself and by the increase of polymer crystallinity due to the nucleation effect. The technique allows to fabricate biodegradable composites with controlled properties by varying concentration and type of the filler as well as degree of PLLA matrix crystallinity. Animal studies revealed that all the composites were biocompatible and non-toxic.

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В журналу Journal of Membrane Science (IF 7,015) опубликована статья с участием сотрудника Института   к.х.н. И.А.Кирилюка (завлаб, ЛАС):

Electrostatic properties of inner nanopore surfaces of anodic aluminum oxide membranes upon high temperature annealing revealed by EPR of pH-sensitive spin probes and labels

 

Abstract

Anodic aluminum oxide (AAO) membranes are versatile nanomaterials that combine the chemically stable and mechanically robust properties of ceramics with homogeneous nanoscale organization that can be tuned to desirable pore diameters and lengths. The AAO substrates feature high surface area that is readily accessible to large and small molecules, making these nanostructures uniquely suited for many possible applications. Examples include templated self-assembly of macroscopically aligned biological membranes and substrates for heterogeneous catalysis. For further development of such applications, one would like to characterize and tune the electrostatic properties of the inner pore surface as well as the local acidity within the nanochannels. Here, we employed electron paramagnetic resonance (EPR) spectroscopy of a small molecule – ionizable nitroxide – as a reporter of the average local acidity in the nanochannels and the local electrostatic potential in the immediate vicinity of the pore surface. The former was achieved by measuring EPR spectra of this molecular probe diffusing in an aqueous phase confined in the AAO nanochannels while for the latter the nitroxide was covalently attached to the hydroxyl group of the alumina surface. We show that the local acidity within the nanochannels is increased by as much as 1.48 pH units vs. the pH of bulk solution by decreasing the pore diameter down to ca. 31 nm. Furthermore, the positive surface charge of the as-prepared AAO could be decreased and even switched to a negative surface charge upon annealing the membranes first to 700 °C and then to 1200 °C. For as-prepared AAO, the local electrostatic potential reaches ψ= (163 ± 5) mV for the nitroxide label covalently attached to AAO and located about 0.5 nm away from the surface. Overall, we demonstrate that the acid-based properties of the aqueous volume confined by the AAO nanopores pores can be tuned by either changing the pore diameter from ca. 71 to 31 nm or by thermal annealing to switch the sign of the surface charge. These observations provide a simple and robust means to tailor these versatile high-surface-area nanomaterials for specific applications that depend on acid-base equilibria.

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В журналу ACS Sustainable Chem. Eng. (IF 6,97) опубликована статья с участием сотрудницы Института   д.х.н. М.В. Еделевой (снс, ЛМР):

No Catalyst Added Hydrogen Peroxide Oxidation of Dextran: An Environmentally Friendly Route to Multifunctional Polymers

 

Abstract

The paper demonstrates a “greener” oxidation of dextran polymer of various molecular masses, the component of many industrially and pharmaceutically important materials, by aqueous H2O2 in a no catalyst added setting that produced a multifunctional oxidized dextran. Specifically, on the top of common functional groups (hydroxo, carbonyl, and carboxylic acids), the freshly peroxide oxidized dextran had also a significant number of peroxo-groups, which endowed the polymer with significant cytotoxic properties, as demonstrated on a larynx carcinoma cell line. We also have shown that the peroxo-groups could be easily removed in an alkaline media to yield nontoxic oxidized dextran polymers.

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