As a result of bright complexation properties, easy functionalization and the ability to self-organize in an aqueous solution, amphiphilic supramolecular macrocycles are being actively studied for ...their application in nanomedicine (drug delivery systems, therapeutic and theranostic agents, and others). In this regard, it is important to study their potential toxic effects. Here, the synthesis of amphiphilic calix4resorcinarene carboxybetaines and their esters and the study of a number of their microbiological properties are presented: cytotoxic effect on normal and tumor cells and effect on cellular and non-cellular components of blood (hemotoxicity, anti-platelet effect, and anticoagulant activity). Additionally, the interaction of macrocycles with bovine serum albumin as a model plasma protein is estimated by various methods (fluorescence spectroscopy, synchronous fluorescence spectroscopy, circular dichroic spectroscopy, and dynamic light scattering). The results demonstrate the low toxicity of the macrocycles, their anti-platelet effects at the level of acetylsalicylic acid, and weak anticoagulant activity. The study of BSA-macrocycle interactions demonstrates the dependence on macrocycle hydrophilic/hydrophobic group structure; in the case of carboxybetaines, the formation of complexes prevents self-aggregation of BSA molecules in solution. The present study demonstrates new data on potential drug delivery nanosystems based on amphiphilic calix4resorcinarenes for their cytotoxicity and effects on blood components.
1,4-Bis(5-phenyl-2-oxazolyl)benzene (POPOP) is a common scintillation fluorescent laser dye. In this manuscript, the synthesis of 2-Ar-5-(4-(4-Ar'-1
-1,2,3-triazol-1-yl)phenyl)-1,3,4-oxadiazoles (Ar, ...Ar' = Ph, naphtalenyl-2, pyrenyl-1, triphenilenyl-2), as PAH-based
-analogues of POPOP, by means of Cu-catalyzed click reaction between 2-(4-azidophenyl)-5-Ar-1,3,4-oxadiazole and terminal ethynyl-substituted PAHs is reported. An investigation of the photophysical properties of the obtained products was carried out, and their sensory response to nitroanalytes was evaluated. In the case of pyrenyl-1-substituted
-POPOP, dramatic fluorescence quenching by nitroanalytes was observed.
Amphiphilic calix4resorcinarenes are a class of macrocyclic compounds with broad potential utility including nanomedicine. Here the synthesis of new carboxybetaine and carboxybetaine ester ...calix4resorcinarene bearing 4-(dodecyloxy)phenyl groups on the lower rim is presented. The compounds were characterized by 1H-NMR, 13C-NMR, 2D NMR, IR, ESI and elemental analysis. The critical association concentration values are 1.00 × 10−5 and 1.18 × 10−5 mol·L−1 for carboxybetain and ester, respectively. The hemolytic activity of the macrocycles and their cytotoxicity against normal (WI-38, Chang liver) and tumor cells (M-HeLa) are also estimated.
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•Nanoscale aggregates of amphiphilic resorcinarenes and crystal violet are described.•Dye binding results in protection from discoloration under hostile conditions.•Encapsulation is ...useful for dye transport and protection in basic/reducing media.
Here, we report on a systematic study of six calix4resorcinarene macrocycles bearing eight carboxylic groups on the upper rim and four different lower rim substituents that are either aliphatic (2, 4, and 5) or alkylaromatic (1, 3, and 6). The macrocycles were studied in their individual aqueous solutions and in the presence of triphenylmethane dye crystal violet. It was found that binding of crystal violet with aggregated macrocycles shields it from the bulk of solution, preventing its discoloration under basic conditions and electrochemical reduction on the glassy carbon electrode. Most efficient shielding, reducing the rate of discoloration more than 173 times, as compared to solution with no macrocycle, was achieved with 6 forming aggregates of average 72 molecules in 0.1mM solutions.
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The synthesis and study of self-association and encapsulation ability of new low toxic conjugate of tetraphenyleneoxypentylcalix4resorcinarene and methoxy-poly(ethylene glycole) ...(C5OPh-mPEG) were described. The conjugate is characterized by 1H, 13C NMR, FT-IR, MS, SLS methods. In an aqueous solution the conjugate form multimicellar nanoparticles with low polydispersity value (0.1, DLS method). The self-association of the conjugate was studied by DLS, fluorescence, fluorescence anisotropy method, TEM, and SAXS methods. The SAXS data were detailed analyzed, and the conjugate associates structure as ellipsoidal core-shell particles was proposed. The encapsulation efficiency is a result of the affinity of the conjugate low rim substituents to substrates and reaches of 39.8, 26.7, and 28.9% toward naproxen, ibuprofen and doxorubicin drugs, respectively.
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Here we present the consecutive study of colloid systems formed by novel isatin derivative as compound with high pharmacological potential and series of carboxyresorcinarenes. The ...azo-modified isatin derivative bearing ammonium moiety (I-3) was synthesized and its antimicrobial activity was investigated. To increase its solubility the solubilization experiment using amphiphilic carboxyresorcinarenes, characterized by low hemolytic activity, was carried out. The I-3 – macrocycles systems were studied by NMR, UV–vis, DLS and TEM. The FT PGSE and 2D NOESY NMR methods demonstrated, that solubilization of I-3 is caused by the incorporation of its molecules in the hydrophobic part of the macrocycles associates. Herewith the loading efficiency of I-3 into the macrocycles associates was reached of 20–30% due to the change of the volume of hydrophobic part of associates by varying the length and structure of hydrophobic substituents of macrocyclic amphiphiles.
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•Carboxycalixresorcinarene stabilizes AgNPs in aqueous colloid solution.•At 1/8 molar ratio macrocycle and CTAB form the hydrophobic associate.•At 1/8 macrocycle/CTAB molar ratio ...AgNPs does not go to organic phase.•The successful AgNPs phase transfer depends on CTAB/macrocycle molar ratio.
The octacarboxylic derivative of tetrapentylcalix4resorcinarene (1) was used as stabilizer for preparation of silver nanoparticles (AgNPs) hydrosol. The calixresorcinarene-capped nanoparticles Ag@1 are stably dispersed in an aqueous colloid solution and have an average diameter of 4–6nm (TEM). The interaction of the macrocycle 1, possessed the receptor properties, with the cationic surfactant cetyltrimetylammonium bromide (CTAB) leads to the hydrophobization of AgNPs hydrosol. It was shown, that macrocycle 1 in its individual solution forms the hydrophobic associate with 8mol of CTAB (1H NMR, 2D NOESY). Various and complicated influence of CTAB/macrocycle molar ratio on the hydrophobization of AgNPs and their transfer into organic phase was demonstrated. The initial Ag@1 and modified Ag@1-CTAB were characterized by UV-vis and FTIR spectroscopy, DLS, and TG/DSC methods It was shown that the efficiency of water/organic phase transfer depends on the macrocycle/surfactant molar ratio. The presented supramolecular approach can be useful to form the ordered nanostructures through supramolecular modification and self-organization of hybrid metal nanoparticles.
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Here we present the supramolecular surfactant-macrocycle system which properties are independent on system composition in the wide range of components concentrations. The study of the ...interaction of octacarboxy-tetra(p-phenylene-oxy-pentyl)calixresorcinarene (C5R) and cetylpyridinuim chloride (CPC) in mixed aqueous solutions were performed by dynamic light scattering and electrophoretic methods, 1H and FT-PGSE NMR methods, absorption and fluorescence spectroscopy, and TEM. The variation of CPC/C5R molar ratio from 30/1 to 10/1 leads to the formation of nanoassociates with similar composition, size, surface potential value, and improved (in compare with CPC) solubilizing properties. The preparation of mixed supramolecular systems which properties are independent on system composition in the wide range of components concentrations is an elegant example of the producing of colloidal materials with the required morphology and properties.
Justification of the study objectives
: Due to the modern demands of the labour market, the reform of the Russian education system requires serious changes, both in the specialists training system ...and in process of their direct activities. In particular, professional training of students with different levels of preparation and specialization requires it.
Goal of research
: to identify features of professional motivation that determine process of professional future self-realization of students with different levels of education.
Research method
: ascertaining psychological pedagogical experiment.
Research result
: the motivational core structure of educational professional motivation of students with different levels of education, which features a certain hierarchy of education motives mediating the process of future professional self-realization.
Main conclusions and their significance
: the study revealed features in the structure of the motivational core of educational and professional motivation of students of different levels of education. This is due to age characteristics, social situation and professional experience. The data of the conducted research can be useful in the implementation of effective psychological and pedagogical support of students of various educational institutions receiving professions of humanitarian orientation, as well as young professionals. In order to harmonize motives in the hierarchy of motivation and increase the level of their professional self-realization.
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► NMR study of aggregation of amphiphilic calixarenes and different guests is present. ► The ‘head-to-tail’ aggregation unusual for amphiphilic calixarenes is observed. ► The binding ...of guest molecules by ‘head-to-tail’ packed aggregates is more efficient. ► The structural control of the guest inclusion into capsule is shown. ► Lifetime of incapsulated methylviologen cation-radical ca.14-fold increases.
Supramolecular nanoaggregates formed through the association of amphiphilic sulfonatomethylated calix4resorcinarenes with different substituents on the lower rim (methyl, pentyl, heptyl) and number of aromatic, aliphatic, and cationic guests differing in their shapes and sizes were investigated in aqueous solution by various NMR techniques (1H, 2D NOESY, FT-PGSE). It was shown that slight variations of the alkyl chain length on the lower rim of calixresorcinarenes dramatically change their aggregation behavior. Unlike the other calixresorcinarenes studied, the “head-to-tail” packing mode is observed for calixresorcinarene with pentyl moieties on the lower rim, which is unusual for amphiphilic calixarene aggregates. This calixresorcinarene demonstrates the stronger binding capacity toward the guest molecules due to their encapsulation into the capsule-like aggregate subunits. The guest–host complexation modifies the properties of both components, with the size of the resulted colloid particles being controlled by the guest nature.
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