Disruption of cholinesterases and, as a consequence, increased levels of acetylcholine lead to serious disturbances in the functioning of the nervous system, including death. The need for rapid administration of an antidote to restore esterase activity is critical, but practical implementation of this is often difficult. One promising solution may be the development of antidote delivery systems that will release the drug only when acetylcholine levels are elevated. This approach will ensure timely delivery of the antidote and minimize side effects associated with uncontrolled drug release. Here, we describe the creation of a new smart system that serves as a carrier for delivering an antidote (i.e., atropine) and functions as a synthetic esterase to hydrolyze acetylcholine. The nanocarrier was synthesized through microemulsion polycondensation of phenylboronic acid with resorcinarenes containing hydroxy, imidazole, and carboxylic groups on the upper rim. The nanocarrier breaks down acetylcholine into choline and acetic acid. The latter acts on the boronate bonds, dissociating them. This leads to the destruction of the nanocarrier and the release of the antidote. The paper covers the creation of the nanocarrier, its physicochemical and biological properties, encapsulation of the antidote, acetylcholine hydrolysis, and antidote release.

This study introduces innovative redox-sensitive polymeric nanocarriers designed to deliver the photosensitizer meso-tetra(N-methyl-4-pyridyl)porphine and enhance anticancer photodynamic therapy. These nanocarriers release the photosensitizer from a hydrophobic core in response to elevated glutathione levels, enabling the generation of reactive oxygen species upon irradiation. The glutathione-sensitive core is constructed using disulfide-linked molecules, while the hydrophilic shell, consisting of a 6-methyluracil derivative, enhances stability and promotes cellular uptake of the photosensitizer. The paper details the synthesis, physicochemical properties, and encapsulation efficiency of the nanocarriers. It further explores how the core structure influences glutathione-induced degradation, photosensitizer release kinetics, and generation of reactive oxygen species under irradiation. Additionally, the study evaluates the hemocompatibility of the photosensitizer/nanocarrier composites and their cytotoxic effects on human liver cells (Chang Liver), healthy human embryonic lung cells (WI38), and cancer cell lines (M-HeLa and HuTu80). Notably, treatment with these composites, followed by irradiation, significantly reduces the viability of the M-HeLa cancer cell line, demonstrating their potential for targeted cancer therapy.

The three-dimensional Ni redox-active metal-organic framework [Ni(bpy)(fcdHp)] based on nickel(ii) cations, anions of ferrocenylbis(H-phosphinic) acid (H2fcdHp), and 4,4′-bipyridine (bpy) was first tested as an oxygen reduction reaction (ORR) catalyst. This compound showed remarkable efficiency and good stability under electrochemical conditions. The diagnostic performance in a proton-exchange membrane fuel cell with this catalyst on the cathode side of the membrane-electrode assembly (MEA) was evaluated for the first time. The catalytic ability of the new system as an ORR catalyst without a platinum catalyst on the anode side was confirmed in a half-cell setup, in which the cathode compartment of the MEA and the anode (liquid electrochemical cell) are separated by a polyelectrolyte membrane.

The strategy implementing multitarget hybrid molecules as potential chemotherapeutic agents to overcome resistance and increase efficiency is promising for different forms of cancer. For this purpose: i) new two-step synthesis of previously unknown 3-(2-aryl-4-oxo-4-(aryl)butyl)quinoxalin-2-ones was developed and ii) arginine modified hybrid phospholipid nanoparticles loaded with quinoxalin-2-ones were produced by using thin lipid film hydration method. The cytotoxic activity was studied against human cancer cell lines M-Hela (cervix carcinoma), HuTu 80 (human duodenal cancer), T 98G (glioblastoma) and human liver cell lines (Chang liver). Quinoxalin-2-one loaded nanoparticles appeared to be monodisperse (PDI <= 0.17) with diameter around 100 nm, high stability (more than 1 year). Arginine-corona with irregular surface and shape was observed by transmission electron microscopy. The most potentially interesting nanotherapeutic forms for promising cancer treatment contain 1-methyl-3-(4-oxo-2,4-diphenylbutyl)-quinoxalin-2-one and 1-methyl-3-(2-(4-nitrophenyl)-4-oxo-4-phenylbutyl)-quinoxalin-2-one. These compounds show much lower IC 50 than the reference standard 5-fluorouracil close to 10 mu M towards M-Hela. Moreover, they show high selectivity index 32 and 4, respectively.

Paraquat, an herbicide used to control annual and perennial weeds, poses risks to human, animal, and environmental health due to its toxicity. This article introduces a nanocontainer designed to bind and neutralize paraquat. The nanocontainer is a nanoscale sphere created through microemulsion polycondensation of resorcinarenes with tyrosine and carboxylate groups and phenylboronic acid. Transmission electron microscopy and dynamic light scattering indicate that the average size of the nanocontainer is approximately 300 nm. Fluorescence and NMR spectroscopy show that the nanocontainer binds paraquat, resulting in a shift of proton signals towards higher fields and fluorescence quenching, with a binding constant of 28000 M−1. This interaction alters the electrochemical properties, contributing to toxicity. In the cyclic voltammetry analysis of paraquat, adding the nanocontainer after three reduction cycles eliminates the reduction peaks, indicating complete neutralization of paraquat. The article details the nanocontainers synthesis, physicochemical properties, binding efficiency of paraquat, and its impact on electrochemical behavior, as well as potential applications for mitigating paraquats harmful effects.

Abstract A new nanocarrier was developed for the delivery of an antidote for poisoning with organophosphorus compounds. The nanocarrier acts as an artificial esterase, hydrolyzing acetylcholine and releasing the antidote (atropine) when acetylcholine level is high. The nanocarrier was made using histidine-containing resorcinarene as a building block. Histidine-resorcinarene was preorganized in a microemulsion media and then polymerized with phenylboronic acid, which acts as a linker between the resorcinarene molecules. Antidote (atropine) was incorporated into the nanocarrier with an encapsulation efficiency of 52.2%. At a neutral pH of 7.4, the nanocarrier hydrolyzes acetylcholine to choline and acetic acid. The acid triggers dissociation of the boronate bonds to dissociate, resulting in nanocarrier degradation and the release of 64.4% of the antidote. Transmission electron microscopy (TEM), dynamic and static light scattering (DLS and SLS, respectively), and IR spectroscopy were utilized to characterize the structure of the nanocarriers. Cyclic voltammetry and NMR spectroscopy were employed to evaluate its ability to hydrolyze acetylcholine. Through fluorescence and NMR spectroscopy, it was demonstrated that the nanocarrier could release substrates (fluorescein and atropine) in in response to the presence of acetylcholine.

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In this paper, the results of the electrocatalytic behavior of a series of copper sodium pectate complexes with different Cu2+ contents (5, 10, 15, 20, 25%) towards the oxygen reduction reaction (ORR) are presented. To investigate the catalytic activity of the studied complexes in ORR, the cyclic voltammograms (CVA) recorded in an oxygen-saturated environment and inert argon gas were compared. Clear reduction peaks are observed in the CVA, confirming the electrochemical activity of the complexes in the oxygen reduction reaction. The kinetics and mechanism of the oxygen reduction reaction on the glassy carbon modified with the complexes in an acidic 0.5 M H2SO4 medium were analyzed. The results obtained by cyclic voltammetry at different scan rates show that the ORR on the copper sodium pectate complexes supported on the glassy carbon is diffusion-controlled. The calculation of the number of electrons participating in the electrochemical reaction was carried out. It was found that the best catalyst of the entire series of samples is a sodium pectate complex with a 5% copper content (n = 4). It was noted that the compound is characterized by a large specific surface area. An increase in the amount of copper ions in coordination biopolymers leads to film formation and a decrease in catalytic activity.

Replacing expensive platinum in electrocatalytic materials by cheaper and readily available alternatives is a paramount task in hydrogen-based energetics.

Brain tumor glioblastoma is one of the worst types of cancer. The blood–brain barrier prevents drugs from reaching brain cells and shields glioblastoma from treatment. The creation of nanocarriers to improve drug delivery and internalization effectiveness may be the solution to this issue. In this paper, we report on a new nanocarrier that was developed to deliver the anticancer drug doxorubicin to glioblastoma cells. The nanocarrier was obtained by nanoemulsion polymerization of diallyl disulfide with 1-allylthymine. Diallyl disulfide is a redox-sensitive molecule involved in redox cell activities, and thymine is a uracil derivative and one of the well-known bioactive compounds that can enhance the pharmacological activity of doxorubicin. Doxorubicin was successfully introduced into the nanocarrier with a load capacity of about 4.6%. Biological studies showed that the doxorubicin nanocarrier composition is far more cytotoxic to glioblastoma cells (T98G) than it is to cancer cells (M-HeLa) and healthy cells (Chang liver). The nanocarrier improves the penetration of doxorubicin into T98G cells and accelerates the cells’ demise, as is evident from flow cytometry and fluorescence microscopy data. The obtained nanocarrier, in our opinion, is a promising candidate for further research in glioblastoma therapy.

This work aimed to obtain an optically transparent electrode based on the oriented nanonetworks of nickel in poly(3,4-ethylenedioxythiophene) polystyrene sulfonate matrix. Optically transparent electrodes are used in many modern devices. Therefore, the search for new inexpensive and environmentally friendly materials for them remains an urgent task. We have previously developed a material for optically transparent electrodes based on oriented platinum nanonetworks. This technique was upgraded to obtain a cheaper option from oriented nickel networks. The study was carried out to find the optimal electrical conductivity and optical transparency values of the developed coating, and the dependence of these values on the amount of nickel used was investigated. The figure of merit (FoM) was used as a criterion for the quality of the material in terms of finding the optimal characteristics. It was shown that doping PEDOT: PSS with p-toluenesulfonic acid in the design of an optically transparent electroconductive composite coating based on oriented nickel networks in a polymer matrix is expedient. It was found that the addition of p-toluenesulfonic acid to an aqueous dispersion of PEDOT: PSS with a concentration of 0.5% led to an eight-fold decrease in the surface resistance of the resulting coating.

Testing on the fuel cell Fig. 2. AFM images of morphologies on the surface of pyrolytic graphite (left), sections along black straight lines (in the center) and particle size distribution histograms (right) of cobalt complexes Сo(Ph-Ph) (A), Co(Ph-Bn) ( B) and Co(Py-p-Tol) (C) Cobalt complexes were obtained in situ by mixing the cobalt salt Co(BF4)2 with a non-coordinating tetrafluoroborate anion with the corresponding ligand in a ratio of 1:2.

This paper considers a method for determining the type of electrical conductivity of a previously developed composite transparent conductive coating based on oriented platinum networks embedded in the polymer matrix. Many researchers have recently been grappling with finding electrically conductive transparent coatings for smart devices with touch screens, particularly an alternative to the massively used indium tin oxide (ITO) having some disadvantages, the most serious of which is the lack of coating flexibility. The latter can be overcome by using various metal-polymer composites with high transparency in the optical range and low surface resistance. However, one should be aware that the type of conductivity depends on both the polymer matrix and the metal framework of a composite. This defines its electrical properties. Therefore, it is important to correctly identify and measure the electrical conductivity. The de-veloped method is based on studying the temperature dependence of the surface resistance in the material.

Coordination biopolymers, namely, nickel complexes of sodium pectate, have been actively studied in recent years as promising representatives of non-platinum catalysts for proton exchange membrane fuel cells. The structure of coordination polymers consisting of natural precursors is complex and not entirely regular. It presents significant difficulties in determining the internal structure of coordination polymers. Identifiable electron paramagnetic resonance (EPR) signals of various Mn2+ units in sodium pectate manganese complexes have provided important structural information in systems similar in composition to nickel coordination biopolymers. In addition, the manganese complexes with the natural pectin polymers themselves are of interest as non-platinum PEMFC catalysts.

Sodium pectate derivatives with 25% replacement of sodium ions with nickel ions were obtained by carbonization to temperatures of 280, 550, and 800 °C, under special protocols in an inert atmosphere by carbonization to temperatures of 280, 550, and 800 °C. The 25% substitution is the upper limit of substitution of sodium for nickel ions, above which the complexes are no longer soluble in water. It was established that the sample carburized to 550 °C is the most effective active element in the hydrogen-oxidation reaction, while the sample carbonized up to 800 °C was the most effective in the oxygen-reduction reaction. The poor performance of the catalytic system involving the pectin coordination biopolymer carbonized up to 280 °C was due to loss of proton conductivity caused by water removal and mainly by two-electron transfer in one catalytic cycle of the oxygen-reduction reaction. The improved performance of the system with coordination biopolymer carbonized up to 550 °C was due to the better access of gases to the catalytic sites and four-electron transfer in one catalytic cycle. The (Ni-NaPG)800C sample contains metallic nickel nanoparticles and loose carbon, which enhances the electrical conductivity and gas capacity of the catalytic system. In addition, almost four-electron transfer is observed in one catalytic cycle of the oxygen-reduction reaction.

Novel cationic amphiphiles of the 3-alkyl-1-(4-methoxyphenyl)-1H-imidazol-3-ium bromide series bearing methoxyphenyl fragments (MPI-n) have been synthesized. Their aggregation properties in aqueous solutions, solubilization capacity, and hemolytic and antimicrobial activities have been investigated by a number of physicochemical methods. Using tensiometry, conductometry, and fluorescence spectroscopy, it was shown that the MPI-n have lower CMCs than their nonfunctionalized counterparts. The unusual alkyl-chain-length-dependent morphology of aggregates is testified for this homological series. Amphiphiles with 12, 14, and 16 alkyl tails are characterized by the formation of micellar aggregates, while a surfactant with a decyl tail is characterized by the formation of larger aggregates with lower surface curvature. The MPI-10 aggregate morphology was rationalized in terms of the packing parameter consideration and was supported by size measurements and the fluorescence probe techniques, which showed that vesicle-like aggregates in close-packing mode probably occur. MPI-n aggregates have exhibited a high solubilization capacity toward hydrophobic azo dye Orange OT. Importantly, amphiphiles studied showed (i) high bacteriostatic activity at the level of ciprofloxacin; (ii) high bactericidal action against all Gram-positive bacteria, including methicillin-resistant strains; (iii) bactericidal properties against Gram-negative bacteria; and (iv) low hemolytic activity.

Transition-metal complexes are candidates for replacing platinum and its combinations with other metals as catalysts for the hydrogen oxidation reaction (HOR) in proton-exchange membrane fuel cells (PEMFCs). The results of catalytic tests of bis(diphosphine) coordination complexes of nickel [Ni(PPh2NPh2)2]·2BF4 and [Ni(PPh2NBn2)2]·2BF4 in liquid-phase oxidation of hydrogen and as components of catalysts for the HOR in PEMFC are analyzed. It was found that the latter complex is a much more efficient catalyst for the HOR in PEMFC than the former. ESR studies demonstrated an increase in the difference between the hyperfine coupling constants on phosphorus nuclei on going from [Ni(PPh2NPh2)2] · 2BF4 to [Ni(PPh2NBn2)2]·2BF4. Significant morphological differences between the complexes on the atomically smooth surface of pyrolytic graphite were revealed by atomic force microscopy.

A glutathione-sensitive nanocarrier for doxorubicin to improve cellular penetration and selective cytotoxic effects on T98G human glioblastoma cells.