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Information × Registration Number 0220U104618, 0120U104868 , R & D reports Title Plasmon hybrid nanosystems "metal-polymer-fluorophore" with enhanced optical response for photonics and biomedical applications. popup.stage_title Head Yeshchenko Oleh A., Доктор фізико-математичних наук Registration Date 24-12-2020 Organization Taras Shevchenko National University of Kyiv popup.description2 Object of research: hybrid nanosystems based on polymer matrices, metal nanoparticles and fluorophores (semiconductor quantum dots or dyes). Purpose: synthesis of hybrid nanosystems such as "metal-polymer fluorophore" and "polymer-fluorophore", which provide high absorption coefficients and photoluminescence intensity and high biological activity; establishment of mechanisms of influence of temperature and optical irradiation on optical properties of such nanosystems for the controlled change of optical properties. Research methods: transmission electron microscopy (TEM), atomic force microscopy (AFM), dynamic light scattering (DRS), absorption and photoluminescence spectroscopy (FL) at different temperatures, thin layer chromatography (TLC), laser-induced surface. Plasmon enhancement of photoluminescence (PL) of the hybrid nanosystem "D-g-PNIPAM / nanoparticles (LF) Au / quantum dots (CT) CdTe" at photon energies corresponding to the radiative recombination of plexitons was revealed. During the heating-cooling cycle of this system, reversible PL quenching was detected, which is the result of the competitive influence of plasmon amplification processes and nonradiative resonant energy transfer from CdTe QD to Au LF at temperature-induced phase transition in the polymer macromolecule. It is concluded that the nanosystem "D-g-PNIPAM / LF Au / CT CdTe" for use as thermosensitive fluorescent optical switches and labels or intracellular fluorescent thermometers. The mechanisms of formation of "photosensitizer Ce6 or DME Ce6 / D-g-PNIPAM" complexes have been studied. It was found that nonpolar DME Ce6 molecules effectively bind to the polymer at a temperature above the critical point of the phase transition, as a result of which they are localized in the depth of the polymer matrix. Polar Ce6 molecules are located in an aqueous environment or on the surface of D-g-PNIPAM regardless of temperature.  Product Description popup.authors Virych Pavlo A. Krupka Oksana М. Kuziv Yuliya I. Kutsevol Natalia V. Nadtoka Sergey О. Tomchuk Anastasia V. Kharchenko Oksana G. Khort Pavlo S. popup.nrat_date 2020-12-23 Close