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A new cross-linking monomer, allyl-bis(benzocyclobuten-4-yl)methylsilane (ABCBMS), was synthesized and its physical properties were investigated. Copolymers of ABCBMS with triethylene glycol dimethacrylate (TGM-3) and bis(methacryloylethylene glycol) carbonate (BMCC-2) were obtained by photo- and thermal polymerization. The final cross-linking of the copolymers took place at 200 °C. Homo- and copolymers of ABCBMS, ABCBMS-TGM-3 (50: 50) and ABCBMS—BMCC-2 (50: 50) exhibit high thermal stability (Td5% = 460, 359, and 352 °C, respectively) and good dielectric properties (e = 2.7–2.8 and tg δ = (3.7–6.7)•10−4 at 10 GHz).

Currently there is a great interest of the science community in extremophile microorganisms, mainly related to the chemical structure and biochemical characteristics. Research has shown the potential of that cell mass such as in the production of carotenoid like bacterioruberin. In this study, process of the cultivation of Halobacterium salinarum biomass with high antioxidant activity is described. Antioxidant activity of the Halobacterium salinarum extract in acetone was studied by HPLC with an amperometric detector. It can be concluded that the antioxidant activity of extracts of halophilic bacteria (5.341 mg/g) exceeds the antioxidant activity of such natural products - recognized sources of carotenoids, such as blueberries and carrots. The obtained results are promising to be used in the agricultural and food industry.

Using a IIIA radiation skin burn model in CD1 mice, we demonstrated that transdermal application of liposomes containing rhAFP; liposomes containing rhGCSF; and liposomes containing rhAFP and rhGCSF on the affected area of the skin within two weeks after irradiation led to a significant reduction in the healing time of the burn wound according to clinical indices. The most effective was the use of liposomes containing rhAFP: the duration of the latent period increased 70%, the duration of the moist epidermitis was reduced by 60%, the duration of the reparative phase was reduced by 32%, and the total healing time of the burn was reduced by 44%, compared to the values for mice with untreated radiation burns. Immunohistochemical studies have shown that application of the studied drugs led to an increase in the survival of stem cells in the hair follicles of the skin: the most pronounced effect on histological indices was noted in the group treated with liposomes containing rhAFP and rhGCSF.

New derivatives of 2-(4-vinylchromen-2-ylidene)malononitrile and 2-(2-vinylchromen-4-ylidene)malononitrile were synthesized using the Knoevenagel reaction of 2-(4-methyl-chromen-2-ylidene)malononitrile and 2-(2-methylchromen-4-ylidene)malononitrile, respectively, with the participation of [1-(2-n-butoxyethyl)-2,2,4,7-tetramethyl-1,2,3,4-tetrahydroquinolin-6-yl)]-carbaldehyde. First hyperpolarizability (β) was calculated for the obtained compounds using the M05-2X functional and 6-31+G (d) basis. Optical properties and solvatochromism in solvents of different polarity (toluene, 1,4-dioxane, chlorobenzene, dichloromethane, DMF, and ethanol) were also investigated.

An approach towards new 2-(4-vinyl-2H-chromen-2-ylidene)malononitriles-derived chromophores was developed. The optical, solvatochromic, and electrochemical properties of the synthesized compounds were studied. The first hyperpolarizability (β) was calculated using M06-2x functional with 6–31+G* basis set. The synthesized compounds absorb at a wide spectral range, from 350 to 770 nm. Divinylthiophene-bridged compound showing the narrowest band gap (1.78 eV), strong solvatochromic effect, and the highest first hyperpolarizability value (β = 47805) was found to be the most promising of the synthesized chromophores.

A series of new electrochromic derivatives of 3-aryl-4,5-bis(pyridin-4-yl)isoxazole was synthesized. Their electrochemical characteristics were studied by cyclic voltammetry, and a low eff ect of the substituents in the isoxazole and pyridinium cycles on the positions of the oxidation and reduction peaks was shown. The electrochromic cells prepared on the basis of the synthesized compounds were reversibly colored into brown upon the application of a voltage of 1.5 V. The spectral properties of the synthesized compounds under the electric field application and their stability for cycling from 0 to 2 V were studied.

Modern approaches to the preparation of monomers and polymers based on benzocyclobutene are considered. The groups of polymers containing siloxane, silyl, polyfluorinated fragments, polyimides, polyamides, polyacrylates, polyolefins, and polyarylenes are distinguished among benzocyclobutene-containing polymers. The basic properties of these polymers (glass transition temperature, decomposition onset temperature, dielectric properties, moisture resistance) are described, and the possibility of their application in the creation of microelectronics devices is evaluated. It has been established that the dielectric constant of most known benzocyclobutene-based polymeric materials lies in the range from 2.3 to 3.07. Fluorine-containing and organosilicon derivatives show the best dielectric properties (2.3–2.38). Polysiloxanes possess the highest thermal stability between considered polymers, demonstrating stability up to 500–550 °C both in inert atmosphere and in air.

A series of new chromophores based on 4-(dicyanomethylene)-2-vinyl 4H-chromenes was synthesized and their physical properties (UV–Vis, NMR, mass spectrometry) were studied. The chromophores show moderate or good solubility in organic solvents. Solvatochromism was investigated for compounds in solvents of low (1.4-dioxane, chlorobenzene, methylene chloride) and high polarity (acetone, acetonitrile). The calculations of the first hyperpolarizability (β) was performed using M052X/6-31+G(d) approximation. Chromophore’s molecules are characterized by high calculated values of the first hyperpolarizability (β) that is only 15% lower than that of FTC analogs.

The structural dependence of silica–liposome hybrids on silanization conditions was investigated. Silica coatings protect liposomes against aggregation, degradation, and leakage, which are important for their application in bioimaging. Liposomes loaded with quantum dots were synthesized and attempts to obtain uniformly sized, silica-coated nanocapsules were made.

One of the promising directions, which have already been applied in many technological processes in manufacturing electronic components and devices, is the use of organic polymer materials. Continuous improvement of electronics and widening the scope of its application has led to strengthening of the requirements to materials used in its production. Polymer materials must possess a set of properties providing efficiency, reliability, and longevity of such devices. Such requirements include thermal stability at temperatures of up to 300–400°C, dielectric properties, optical transparency in the UV, visible, and near-IR ranges, chemical stability, etc. This review article covers the available information on existing polymer materials on the basis of benzocyclobutene and its derivatives, and their physicochemical properties. Comparative evaluation of materials on the basis of benzocyclobutene and its derivatives, including analogs, is made, and their application in electronic devices is described.

New 4-oxo-2-vinyl-4H-chromene-3-carbonitrile derivatives have been synthesized by the Knoevenagel reaction of 2-methyl-4-oxo-4H-chromene-3-carbonitrile with aromatic and heteroaromatic aldehydes. Spectral properties of the obtained compounds have been studied.

New derivatives of 2-oxo-4-vinyl-2H-chromene-3-carbonitrile have been synthesized by the Knoevenagel reaction of 4-methyl-2-oxo-2H-chromene-3-carbonitrile with aromatic and heteroaromatic aldehydes. The first hyperpolarizability β for the obtained compounds was calculated using M05-2X functional and 6-31+G(d) basis set; their optical properties and solvatochromism in solvents of various polarity were examined. The crystal structure for one representative of the synthesized compounds was determined by XRD.

A test method is developed for determining benzo[a]pyrene in natural water, based on the use of a polyethylene filter (frit) with adsorbed specific antibodies, placed within a transparent column. In passing a test solution, the analyte is adsorbed on the frit similarly to the process implemented in immunoaffinity preconcentration. The added conjugate of a labeled analyte takes the remained vacant binding sites of antibodies. Luminescent semiconductor nanoparticles (quantum dots) CdSe/ZnS, used as labels, enable visual determination under irradiation with UV light. The limit of detection for benzo[a]pyrene in water is ~0.5 ng/mL.

Bicyclo[4.2.0]octa-1,3,5-trien-3-yl-dimethyl-((E)-styryl)-silane was synthesized via three stage synthesis starting from benzocyclobutene and (2-bromo-vinyl)-benzene. The structure of the product was determined using 1H- and 13C-NMR and HRMS.

Di(bicyclo[4.2.0]octa-1(6),2,4-trien-3-yl)dimethylsilane (DiBCB-DMS) was synthesized as a promising monomer for polymer coating production with good dielectric properties for electronics. DiBCB-DMS was characterized by 1H, 13C NMR, IR, UV/VIS, and HRMS analysis.

The physical limitations of the amount of data stored on optical media are pushing researchers to create new materials and methods for recording and reading data. One of the promising areas is the use of fluorescent compounds. Within the framework of this work, polymer structures of optical fluorescent memory with a recording medium based on 3-(thiophene-2-carbonyl) -2- (furan-2-yl) -4n-chromen-4-one in polymethylmethacrylate have been fabricated and investigated. The concentration of chromone was 5% (wt.), Which during recording made it possible to achieve optical density values at λ = 442 nm in the range of 0.01 – 0.02 with a central layer thickness of 1-3 µm. In the structures developed, the process of two-photon information recording and fluorescent parallel reading is realized. The threshold recording power density for providing a two-photon process was (5.1 ± 0.4) 105 W/cm2.

4-(2-Bromovinyl)benzocyclobutene was prepared via a five stage synthesis starting from benzocyclobutene in an overall 30% yield. 4-(2-Bromovinyl)benzocyclobutene has a potential applications in synthesis of monomers for dielectric materials.

A new adamantan-2-ol with a 2-bicyclo[4.2.0]octa-1,3,5-trien-3-yl substituent in the position 2 was synthesized via two stage synthesis starting from benzocyclobutene and adamatan-2-one. The structure of the title compound was determined using 1H-and 13C-NMR, HRMS and XRD.

The approaches to the synthesis of new derivatives of 2-7-dibromofluorene and benzocyclobutene have been investigated. For this purpose 9-bicyclo [4.2.0] octa-1 (6), 2,4- trien-3-yl-2,7-dibromo-9H-fluoren-9-ol was synthesized by reaction of 2,7-dibromo-fluoren -9- one with 3-benzocyclobutene magnesium bromide. The possibility of reduction and substitution of the hydroxyl group at position 9 of the obtained compound with aromatic substituents under conditions of acid catalysis is demonstrated. Target compounds were obtained in yields from 75 to 90%.

New fluorescent derivatives of 1-(thien-2-yl)-3-methyl-9H-thieno[3,4-b]-chroman-9-one are synthesized and their spectral properties studied. The prepared fluorescent compounds are combined with several photochromic benzothienyl dihetarylethenes to provide mixed systems exhibiting reversible photo-induced fluorescence modulation in solution. The obtained results are promising for the development of polymeric photochromic recording media with a non-destructive fluorescence readout of optical information for RAM with extra large information capacity.

New photosensitive 3-acyl-2-(2-furyl)thiochromones, potential components for multilayer media of archive-type optical discs, were prepared and tested for photorearrangement.

Hybrid nanostructures including modified fullerene C60 and fluorophoric (E)-2-Cyano-3-(9-ethyl-9Н-carbazole-3-yl)-acrylic acid (cyanoacrylic acid I) were created. Spectral properties (absorption and luminescence spectra) of the hybrid nanostructures were investigated. It was established what molecules C60 strongly affected spectral properties of cyanoacrylic acid I in the hybrid nanostructures. Luminescence quenching of fluorophore and a change of luminescence features were observed in the hybrid nanostructures.

Electrochemical and optical properties of a new class of electrochromic 3-aryl-4,5-bis (pyridin-4-yl)isoxazoles derivatives containing conjugated pyridine fragments were investigated comparing with their precursor 1,2-bis(4-pyridinyl)ethylene derivative. Electrochromic cells based on synthesized substances were reversibly colored in brown upon the application of a voltage of 1.5 V.

New cross-linking monomer based on 1,3-diallyl-1,3-di[bicyclo[4.2.0]octa-1,3,5-trien-3-yl]-1,3-dimethyl-siloxane (BCB-All) was synthesized and its physical properties were studied. BCB-All was incorporated into copolymer with TGM-3 and PFHDA by two stage thermal polymerization. The cross-linking of the copolymers occurs by thermo-initiated ring-opening reaction of BCB at 120-200°C. Resulting BCB-All homopolymer, BCB-All-TGM-3 (50:50), and BCB-All-PFHDA (50:50) copolymers have high thermal stability (Td5%,=464°C, 322°C, 435°C respectively) and good dielectric properties (ε=2.34-2.48 at 10HHz).

The review considers the potential of hybrid nanostructures in creating smart materials with optically controlled properties. The goals and technologies of development of stable hybrid nanostructures are analyzed. Some experimental results concerning smart materials with optically controlled properties, including those based on a unique photochromic material bacteriorhodopsin, which have a great potential in the development of a new type information systems, are summarized.

Liposomes loaded with water-soluble and water-insoluble quantum dots (QD) were for the first time applied as labels in different heterogeneous immunoassays for the determination of food contaminants, using mycotoxin zearalenone (ZEN) as a model. A great deal of work was devoted to the optimal choice of phospholipids for the liposomes preparation and to the factors which are important for the stability and size of obtained liposomes. Thin-film hydration and reverse-phase evaporation techniques were evaluated in terms of stability of the obtained liposomes and their efficiency for QD loading. Conjugation of liposomes with proteins and the influence of cross-linkers to the nonspecific interaction of the obtained liposomes with the surface of microtiter plates and cartridges were investigated and 3-(2-pyridyldithio)propionic acid N-hydroxysuccinimide ester was found as the optimal cross-linker. The limits of detection (LOD) for ZEN of fluorescence-labeled immunosorbent assays were 0.6 μg kg(-1), 0.08 μg kg(-1), and 0.02 μg kg(-1), using QD, liposomes loaded with water-soluble QD, and water-insoluble QD, respectively. Similarly, the developed qualitative on-site tests using the different QD labels and taking into account the EU maximum residues level for ZEN in unprocessed cereals showed cutoff levels of 100, 50, and 20 μg kg(-1).

A quantitative fluorescence-labeled immunosorbent assay and qualitative on-site column tests were developed for the determination of aflatoxin M1 in milk products. The use of liposomes loaded with quantum dots as a label significantly increased the assay sensitivity by encapsulating multiple quantum dots in a single liposome and, therefore, amplifying the analytical signal. Two different techniques were compared to obtain aflatoxin-protein conjugates, used for further coupling with the liposomes. The influence of nonspecific interactions of the liposome-labeled conjugates obtained with the surface of microtiter plates and column cartridges was evaluated and discussed. The limit of detection for fluorescence-labeled immunosorbent assay was 0.014 mu g kg(-1). For qualitative on-site tests, the cutoff was set at 0.05 mu g kg(-1), taking into account the EU maximum level for aflatoxin M1 in raw milk, heat-treated milk, and milk for the manufacture of milk-based products. The direct addition of labeled conjugate to the milk samples resulted in an additional decrease of analysis time. An intralaboratory validation was performed with sterilized milk and cream samples artificially spiked with aflatoxin M1 at concentrations less than, equal to and greater than the cutoff level. It is shown that milk products can be analyzed without any sample preparation, just diluted with the buffer. The rates for false-positive and false-negative results were below 5 % (2.6 % and 3.3 %, respectively).

The regioselective Friedel–Crafts acylation of 1,2-bis(2-methylbenzo[b]thien-3-yl)hexafluorocyclopentene was developed. Depending on the reaction conditions, mono- or bis(bromoacetyl) derivatives are formed as single products in good yields. Further heterocyclizations involving α-bromoketone moieties gave a series of new photochromic compounds.

Acylation of 1,2-bis(2-methylbenzo[b]thiophen-3-yl)cyclopent-1-ene gave symmetric and asymmetric 1,2-dihetarylethenes, which are of interest as photosensitive components of photochromic recording media for optical read/write storage. The formation of the photoinduced diffraction grating in a dihetarylethene-containing photochromic photorefractive layer of a waveguide multilayer system was studied.

Methods have been developed for the synthesis of new photosensitive compounds based on the reaction of N,S,O-nucleophiles with 3-acyl-2-(5-bromofur-2-yl)chromones and 3-acyl-2-(5-bromomethylfur-2-yl)chromones. The relationship between the spectral properties and the structure of compounds has been shown.

The Suzuki cross-coupling of 1,2-bis(6-iodo-2-methylbenzo[b]thiophen-3-yl)hexafluorocyclopentene and (het)arylboronic acids depending on the reaction conditions affords bis- or mono-adducts. The latter on next cross-coupling with different boronic acid give unsymmetrical dihetarylethenes. Spectral-kinetic studies of the photoinduced cyclization of the compounds obtained were performed.

A simple and general route to 3-cyanochromones containing various substituents on position 2 of the ring is developed. The method is based on condensation of 3-(2-hydroxyphenyl)-3-oxopropionitrile with acid chlorides or anhydrides in pyridine at room temperature.

This manuscript describes synthesis and followed application of silica-coated liposomes loaded with quantum dots as a perspective label for immunoaasay. The hollow spherical structure of liposomes makes them an attractive package material for encapsulation of multiple water-insoluble quantum dots and amplifying the analytical signal. Silica coverage ensures the stability of the loaded liposomes against fusion and internal leakage during storage, transporting, application and also provides groups for bioconugation. For the first time these nanostructures were employed for the sensitive multiplex immunochemical determination of two analytes. As a model system mycotoxins zearalenone and aflatoxin B1 were detected in cereals. For simplification of multiassay results’ evaluation the silanized liposomed loaded with QDs of different colors were used. The IC 50 values for the simultaneous determination of zearalenone and aflatoxin B1 were 16.2 and 18 µg kg −1 for zearalenone and 2.2 and 2.6 µg kg −1 for aflatoxin B1 in wheat and maize, respectively. As confirmatory method, liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) was used.

Based on the condensation of carboxylic acid chlorides or anhydrides with 3-(2-hydroxyphenyl)-3-oxopropionitrile (I), a general synthesis of the title compounds (III) is described.

Methods have been developed for the synthesis of new photosensitive compounds based on the reaction of N,S,O-nucleophiles with 3-acyl-2-(5-bromofur-2-yl)chromones and 3-acyl-2-(5-bromomethylfur-2-yl)chromones. The relationship between the spectral properties and the structure of compounds has been shown.