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There are some types of breast cancer (BC) that depend on their molecular characteristics. However, lately researchers provide date regarding the presence of additional receptors of triple negative breast cancer (TNBC). One of them is LA R-subtype that has androgen receptors (AR) on breast cancer cells. The role of AR in the development of this pathology is still controversial. According to some authors, stimulation of AR leads to the proliferation suppression, in the opinion of others – to the activation and potentiation of tumor invasion. There is also a version of the dichotomous effect of androgens that depends on the concentration of this hormone. The various effects of LA R-subtype therapy of BC are also explained by the presence of many other regulator proteins that interact with AR. The first attempts to treat BC with androgen have begun since the 40s of the last century, but in those years it did not have the desired effect and was not used until recently. Currently, the basic mechanisms of the effect of androgens on BC cells on the molecular level are known, and researches try to use androgen therapy, also in combination with aromatase inhibitors to increase the concentration of endogenous testosterone. The effects of selective androgen receptor modulators and anabolic steroids are being studied. However, in the last decade, the largest number of studies focused on the study of anti-androgen therapy. Patients receive AR antagonists, such as enzalutamide, bicalutamide, that are prescribed for prostate cancer. Enzalutamide blocks both androgen- and estrogen-mediated tumor growth, and therefore can be used regardless of the presence of estrogen receptors (ER), in contrast to bicalutamide. The results showed a significant increase in disease free survival up to 16.5 months in patients with hormone positive BC.

Direct metallation of 2-hydroxyphthalocyanine J-type slipped-cofacial dimeric ligand by Mg, Zn, Cu, Ni and Co salts has been carried out to obtain corresponding metal complexes selectively without any noticeable dissociation or polymerization of the starting ligand. Integrated analysis of aggregation properties in the synthesized series has been conducted with the involvement of AFM microscopy, UV/Vis spectroscopy and theoretical assessment. As a result, a nonlinear relationship between absorption and concentration was found, with aggregation beginning to appear at concentrations above 3.3 × 10−5 mol L−1 with predominant formation of trimers from the dimeric molecules in THF solutions.

Spectroscopy based on surface enhanced Raman scattering (SERS) is widely used as a method with extremely high sensitivity for molecular and chemical analysis. We have developed thin-film sandwich structures, in which, when used as sensitive elements for detecting organic compounds at low concentrations, high-amplitude spectra of surface enhanced Raman scattering are observed. Using gas-phase cryochemical synthesis and thermal sputtering in vacuum, SERS active sandwich structures Ag&ndash, poly(chloro-p-xylylene)&ndash, Ag (Ag&ndash, PCPX&ndash, Ag) were obtained. In the process of creating sandwich structures, the upper silver film takes the form of a complex island topology with submicron sizes. A series of samples were made with different thicknesses of the polymer and upper silver layers. SERS spectra of the analyte chemically adsorbed on the film surface were obtained, demonstrating a significant amplification (up to 104) compared with the control sample. The dependence of the gain on the silver concentration is characterized by a maximum polymer layer thickness of 600 nm and a 30 nm thick upper silver layer. A selective amplification of the low molecular weight compound spectra with respect to proteins was observed. A semi-empirical model is proposed that is in good agreement with the experimental results.

Novel 3-(ethylthio)phenyl-substituted phthalocyanine and naphthalocyanine zinc complexes were synthesised with high yields. The Suzuki cross-coupling reaction provides selective approaches to the initial mono- or di- 3-(ethylthio)phenyl-substituted phthalonitriles. The complexes obtained were characterised by 1H nuclear magnetic resonance spectroscopy and high-resolution mass spectrometry. Observation of the nuclear Overhauser effect was used for aromatic proton assignment. The correlation between the number of 3-(ethylthio)phenyl groups, the size of the π-system and the position of the Q-band was defined. Visualisation of the influence of increasing π-system size on aggregate size was provided by atomic force microscopy.

Novel terbium(III), dysprosium(III), erbium(III) and lutetium (III) tetrapyrazinoporphyrazines with bulky 4-(tert-butyl)-phenyl groups, were obtained by metallation of porphyrazine ligand in high yields. The target complexes were identified by high-resolution matrix assisted laser desorption/ionization mass spectrometry, infrared and nuclear magnetic resonance spectroscopy. In nuclear magnetic resonance spectra, the proton signals demonstrate strong shifts for complexes with paramagnetic ions in comparison with lutetium one. The impact of peripheral (tert-butyl)phenyl groups and central ion nature on position of the main absorption bands in UV–Vis spectra was investigated. Two blends of gold nanoparticles (5 and 60 nm in diameters) and lutetium complex were prepared. The influence of the size of bare Au nanoparticles on core-shell structure of hybrid blends was investigated by transmission electron microscopy and atomic force microscopy. The nonlinear optical behavior of hybrid nanoparticles as well as initial lutetium (III) tetrapyrazinoporphyrazine was carried out using Z-scan measurements.

Selective synthetic approaches to novel single- and multiple-decker terbium(III) phthalocyaninates, bearing peripheral phenyl groups, were developed. The compounds were identified by nuclear magnetic resonance spectroscopy, high resolution mass spectrometry, Fourier-transform infrared and UV–Vis spectroscopy. From the X-ray data for initial 1,2-dicyano-4,5-diphenylbenzene it was shown that phenyl groups are not in the same plane, and dihedral angle between them equals 64°. Strong upfield shifts of the aromatic proton signals up to −131.62 ppm in the case of a triple-decker complex were found in the nuclear magnetic resonance spectra due to paramagnetic nature of terbium(III) ion. Stronger intramolecular interactions are observed for the sandwich-type phenyl-substituted terbium complexes comparing to tert -butyl-substituted analogs, earlier described in literature. In the case of the double-decker compound, this results in 142 nm hypsochromic shift of the intervalence absorption band. DC conductivity measurements were carried out for terbium bis phthalocyaninate. The formation of the ring-shaped self-assembled aggregates with a diameter of 400 nm was observed in thin solid films of the prepared terbium(III) compounds by atomic force microscopy.

Anomalous optical response for the metasurface fabricated from silicon resonators is investigated. Resonators have form of 3D micro cones – tips that are covered by semicontinuous silver film. Thus prepared metasurface exhibits anomalous optical response due to the excitation of metaldielectric resonances in visible and near IR spectral ranges. We investigate the effect of the “extraordinary” optical diffraction by tip-shaped metasurface. The multiple metal-dielectric resonances result in huge enhancement of the local electric field in-between metal particles placed on the surface of dielectric cones. SERS phenomenon is investigated by immobilization of DTNB (5,5’- dithio-bis-[2-nitrobenzoic acid]) molecules of on the metasurface.

Observation of the wanted Raman signal from SERS substrates is hampered by the background luminescence. We investigate the metasurface made of periodic silicon micro bars with thin silver layer on the top. The computer simulations as well as real experiment reveal the anomalous optical response of the metasurface is due to the excitation of the metal-dielectric surface resonances. We demonstrate the enhanced Raman signal from the organic molecules of 5,5-dithio-bis[2-nitrobenzoic] acid deposited on the microbar metasurface. The microbar metasurface exhibits large Raman/luminescence (signal/noise) ratio. As result it operates as an efficient SERS substrate.

The first examples of planar binuclear porphyrazines sharing a common benzene or naphthalene ring based on a 3,4-thiophene moiety have been synthesized and characterized using nuclear magnetic resonance spectroscopy, high-resolution mass spectrometry, electronic absorption spectroscopy and magnetic circular dichroism. In order to enhance the interpretation of the electronic structures, quantum chemical studies were carried out. The formation of nanoaggregates in a solid film was shown using atomic force microscopy.

In this paper, we investigate the potential of facet structures of cerium dioxide for the purpose of increasing the intensity of the surface enhancement Raman scattering (SERS) signal. During the studies, a new metamaterial is developed. The metamaterial is based on facet cerium dioxide films and plasmonic nanoparticles that are immobilized on its surface. The new metamaterial provides an additional SERS signal amplification factor of more than 200. Thus developed material offers the prospect of increasing the sensitivity and selectivity of biochemical and immunological analysis.

A comprehensive study of the microstructure of poly(p-xylylene)-silver (PPX-Ag) nanocomposites is carried out using the method of light scattering indicatrix analysis. A stand for measurements of light scattering indicatrix and integral light scattering is created. Theoretical calculations of the PPX-Ag scattering indicatrices using Mie theory are performed taking into account the features of the microstructure of the nanocomposite. Good agreement of the experimental and theoretical studies of the PPX-Ag scattering indicatrices is obtained.

An efficient synthetic approach to a novel substituted tetrathieno[2,3- b ]porphyrazine, its Mg, Zn, Lu complexes and a Lu triple-decker complex was developed. Spectral properties and aggregation phenomena of the target compounds were investigated by UV/Vis spectroscopy and atomic force microscopy (AFM). Electrochromic behaviour of the Zn complex was studied by electrochemistry and spectroelectrochemistry.

The processes of formation of metal-polymer poly-para-xylylene-Ag nanocomposites by solidphase cryochemical synthesis are studied. The temperature dependences of the electrical resistivity of the composites measured in the course of polymerization, which involves heating the cocondensate of p-xylylene monomer and metal particles, and on completion of the polymerization are presented. The findings are correlated to the results of the structural investigation of the obtained composite by the atomic-force microscopy, transmission electron microscopy, and x-ray diffraction. An empirical model of the process of nanocomposite formation is proposed. The mechanisms of electric conduction in nanocomposites are discussed.

The results from magnetooptical studies of the influence of magnetochemical effects on the surface morphology and local magnetic properties of FeN alloy thin films and thin-film systems that consist of alternating silicon dioxide and FeN layers of submicron thickness, are shown. The dramatic influence of chemical etching on the surface morphology and magnetic characteristics of the investigated samples is revealed.

Further enhance of the Raman scattering is the priority for the development of the modern molecular diagnostic methods. Expected increasing in detection sensitivity of the biological and chemical agents provides substantial progress in such areas as: proteomics (discovery of new disease markers), pharmacokinetics of drugs, analysis of toxins and infections agents, drug analysis, food safety, and environmental safety.In this paper we investigated the possibility of the facet structures, based on cerium dioxide to further enhance the SERS signal. During the studies a new metamaterial was developed. The metamaterial is based on the facet cerium dioxide films and plasmonic nanoparticles that are immobilized on its surface. The new metamaterial provides additional SERS signal amplification factor of 211. Thus developed material offers the prospect of increasing the sensitivity and selectivity of biochemical and immunological analysis.

Using as an example SiO2/Cu/SiO2 and Al2O3/Cu/Al2O3 coatings in the wavelength range lambda=0.35-2.5 µm, the optical properties of the metal layers in three-layer insulator/metal/insulator systems have been studied. The indicated coatings are obtained by the method of layer-by-layer electron-beam sputtering on silicate glass. The dispersion dependences of the refractive index n and absorption index k of the intermediate copper layer in SiO2/Cu/SiO2 and Al2O3/Cu/Al2O3 coatings is determined for the first time, using a computational matrix method to calculate the optical constants (n and k) of the separate layers that make up the layered system. It is shown that the properties of the metal films in the coatings under consideration are mainly determined by microstructural effects.