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Статьи в научных журналах

    A Highly K+-Selective Phenylaza-[18]crown-6-Lariat-Ether-Based Fluoroionophore and Its Application in the Sensing of K+ Ions with an Optical Sensor Film and in Cells, S. Ast, T. Schwarze, H. Müller , A. Sukhanov, S. Michaelis, , J. Wegener, O. S. Wolfbeis, T. Körzdörfer, A. Dürkop, and H.-J. Holdt , Chemistry - A European Journal , Vol 19, pp. 14911-14917, Oct. 2013, DOI: 10.1002/chem.201302350
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Herein, we report the synthesis of two phenylaza-[18]crown-6 lariat ethers with a coumarin fluorophore (1 and 2) and we reveal that compound 1 is an excellent probe for K+ ions under simulated physiological conditions. The presence of a 2-methoxyethoxy lariat group at the ortho position of the anilino moiety is crucial to the substantially increased stability of compounds 1 and 2 over their lariat-free phenylaza-[18]crown-6 ether analogues. Probe 1 shows a high K+/Na+ selectivity and a 2.5-fold fluorescence enhancement was observed in the presence of 100 mm K+ ions. A fluorescent membrane sensor, which was prepared by incorporating probe 1 into a hydrogel, showed a fully reversible response, a response time of 150 s, and a signal change of 7.8 % per 1 mm K+ within the range 1–10 mm K+. The membrane was easily fabricated (only a single sensing layer on a solid polyester support), yet no leaching was observed. Moreover, compound 1 rapidly permeated into cells, was cytocompatible, and was suitable for the fluorescent imaging of K+ ions on both the extracellular and intracellular levels.
  • Solid-Phase-Enhanced Photothermal Lensing with Mesoporous Polymethacrylate Matrices for Optical-Sensing Chemical Analysis , D.A. Nedosekin, N. V. Saranchina, A.V. Sukhanov, N.A. Gavrilenko, I.V. Mikheev, M.A. Proskurnin , Applied Spectroscopy , Vol 67, Issue 7, pp. 702-717, Jul. 2013.

  • Procedures for the photothermal lens determination of metals and organic compounds, on the basis of solid-phase mesoporous optical-sensing materials (polymethacrylate [PMA]) matrices with immobilized reagents, were developed. These procedures combine (i) selective and efficient preconcentration of trace substances to be analyzed in specially designed and synthesized transparent mesoporous PMA plates; (ii) sensitive determination with the reliable and traceable photometric reactions previously developed for classical spectrophotometry; and (iii) the sensitivity enhancement of photothermal lens detection in polymers, which provides at least a ten-fold increase in sensitivity compared with solutions due to polymer thermo-optical properties (solid phase‐enhanced thermal lensing). It is shown that the overall sensitivity of photothermal lens measurements in PMA matrices is two orders higher than photometric absorbance measurements for the same excitation source power, which is in good agreement with the expected theoretical sensitivity. Changes in the preparation of transparent PMA plates and analytical procedures for photothermal measurements compared with spectrophotometry are discussed. PMA matrices modified with various analytical reagents were applied to trace determination of Hg(II), Fe(II), Ag(I), Cu(II), and ascorbic acid, with subnanomolar to nanomolar limits of detection.
  • Potentials of thermal lens spectroscopy for polymethacrylate optical sensors, N. V. Saranchina, A. V. Sukhanov, D. A. Nedosekin, N. A. Gavrilenko, M. A. Proskurnin, Journal of Analytical Chemistry , Vol 66, Issue 6, pp. 623-628, Jun 2011, DOI: 10.1134/S106193481106018

  • The sensitivity of the earlier proposed procedures for the determination of iron(II, III) with 1,10-phenanthroline, silver(I) with dithizone, mercury with copper(II) dithizonate, copper(II) with lead diethyldithiocarbamate, and ascorbic acid with 2,6-dichlorophenolindophenol using polymethacrylate opti- cal sensitive elements for solid phase spectrophotometry is enhanced through the use of thermal lens spec- trometry as the most sensitive method of molecular absorption spectroscopy. The limits of detection for all photometric reactions in the polymethacrylate matrix are reduced by an order of magnitude (to 10 nM) with- out substantial changes in the experimental conditions.
  • Redox and acid-base properties of 2,6-dichlorophenolindophenol immobilized on a polymethacrylate matrix, N. A. Gavrilenko, A. V. Sukhanov, O.V. Mokhova , Journal of Analytical Chemistry , Vol 65, Issue 1, pp. 17-20, Jan 2010, DOI: 10.1134/S1061934810010041

  • The effect of the immobilization of 2,6-dichlorophenolindophenol (DCIP) on a polymethacrylate matrix on its redox and acid-base properties was studied. The ionization constant and formal redox potentials of the immobilized DCIP were determined by solid-phase spectrophotometry. It was shown that the acidity constant and the formal potentials of DCIP decreased upon the immobilization in the polymethacrylate matrix. The results of studying the interaction of ascorbic acid with immobilized DCIP are presented.
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