Iryna Kravchenko

Toxic metals are known pollutants to pose high toxicity to the environment and humans when they occur above threshold levels. In order to meet the requirements of environmental quality standards established by pertinent regulations, analytical processes that perform quick, accurate, and precise determination of such pollutants are becoming more and more important. This study offers a rapid, efficient, and sensitive method for cadmium determination in tap water samples by slotted quartz tube–flame atomic absorption spectrometry (SQT-FAAS). A spray-assisted droplet formation-liquid phase microextraction (SADF-LPME) method was developed to simultaneously extract and preconcentrate cadmium ions using microliter volumes of solvent in agreement with green analytical chemistry. Hydrazone type complexing ligand and diphenylcarbazone were tried to check the complex formation efficiencies. The optimum extraction conditions were determined by comprehensive examination of the parameters affecting complexation and extraction. The limit of detection/limit of quantification values for the DPC and L-4 hydrazone ligands under optimum conditions were 0.70/2.4 µg/L and 1.1/3.5 µg/L, respectively. The linear dynamic range for cadmium was found to be 2.0–75 µg/L, and the correlation coefficient (R²) was higher than 0.99. The method has been successfully applied to tap water samples, with recovery results close to 100% validating the accuracy of the method.

The coordination compound [NiCl₂L(2-PrOH)]_n (where L is 2-(4-bromophenoxy)acetohydrazide; 2-PrOH is isopropanol) was obtained for the first time. The complex was characterized by means of elemental analyses, molar conductance, thermogravimetric analysis, IR spectroscopy, and single crystal X-ray diffraction analysis. It was determined that the coordination compound exhibits a polymeric structure. The complexing agent is six-coordinated, and its distorted octahedron forms due to the bidentate coordination of 2-(4-bromophenoxy)acetohydrazide through the carbonyl oxygen atom and the amine nitrogen. The oxygen of the molecule of isopropanol, the chlorine atom, and two chlorine atoms serve as bridges between two metal atoms.

Мета роботи. Дослідження протизапальної активності м’якої лікарської форми з естерами ібупрофену в поєднанні з низькочастотним ультразвуком. Матеріали і методи. Протизапальну дію синтезованих сполук оцінювали на моделі карагенінового запалення шляхом субплантарного введення розчину карагеніну в задню кінцівку щурів. Для посилення проникності шкіри використовували низькочастотний ультразвук із частотою 20–25 кГц. У досліджені були використанні білі щури-самці лінії Вістар масою 180–220 г. Динаміку зміни запального процесу визначали за допомогою виміру товщини та об’єму уражених кінцівок. Як референс-препарат використовували 5 % мазь ібупрофену «Долгіт крем». Статистичні показники вираховували за допомогою програмного пакета Microsoft Excel. Результати й обговорення. За результатами дослідження об’єму уражених кінцівок встановлено, що від початку 4-ї доби лікування етиловий естер ібупрофену в поєднанні з низькочастотним ультразвуком демонструє кращу протизапальну активність, ніж референс-препарат. Аналогічна тенденція спостерігається при визначенні товщини ураженої кінцівки. Так, у групі тварин, яких лікували етиловим естером ібупрофену, товщина уражених кінцівок досягає меж фізіологічної норми на 6-й день лікування, тоді як у групі тварин, лікованих гексадециловим естером ібупрофену – на 7-й день. Висновки. Отримані результати свідчать про те, що використання синтезованих естерів ібупрофену в поєднанні з низькочастотним ультразвуком приводить до підвищення їхньої протизапальної активності. Важливо зазначити, що вища протизапальна активність притаманна саме етиловому естеру ібупрофену.

Hydrazones based on mono- and bicyclic terpenoids (verbenone, menthone and carvone) have been investigated in vitro as potential biomembrane penetration enhancers. In this regard, liposomes composed of lecithin or cardiolipin as phospholipid phase components with incorporated fluorescence probes have been prepared using the thin-film ultrasonic dispersion method. The mean particle size of the obtained liposomes, established using laser diffraction, was found to be 583 ± 0.95 nm, allowing us to categorize them as multilamellar vesicles (MLVs) according to their morphology. Pursuant to fluorescence analysis, we may assume a reduction in microviscosity and, consequently, a decrease in the packing density of lecithin and cardiolipin lipids to be the major mechanism of action for terpenoid hydrazones 1–15. In order to determine the molecular organization of the lipid matrix, lipids were isolated from rat strata cornea (SCs) and their interaction with tested compounds was studied by means of Fourier transform infrared spectroscopy. FT-IR examination suggested that these hydrazones fluidized the SC lipids via the disruption of the hydrogen-bonded network formed by polar groups of SC constituents. The relationship between the structure of terpenoid hydrazones and their ability to enhance biomembrane penetration is discussed.

2-Propyl-N′-[1,7,7-trimethylbicyclo[2.2.1]hept-2-ylidene]pentanehydrazide was obtained in 80% yield via the Einhorn variation of the Schotten–Baumann method by (+)-camphor hydrazide condensation with valproic acid (VPA) chloride. The structure of the titled compound was verified by Raman, FTIR, ¹H-NMR, and ¹³C-NMR spectral analysis along with FAB-mass spectrometry. Thermal properties of synthesized derivative were elucidated by DSC and its purity by HPLC. The compound was successfully tested as a potential anticonvulsant agent based on models of chemically- and electrically-induced seizures.

Introduction: The aim of this research is centered on phytochemical analysis and anti-inflammatory activity of Cladophora aegagropila extract. Methods: Total flavonoid content in the appropriate ethanol extract of C. aegagropila was determined using the spectrometric method. Anti-inflammatory activity was evaluated by the models of carrageenan-induced and allyl isothiocyanate-induced (AITC-induced) inflammation of hind limb in rats. Experimental animals were divided into 3 groups, 5 animals each: 1st group – control; the animals without therapy of induced inflammation, 2nd group – animals were treated with application of 5% ointment containing C. aegagropila; 3rd group – animals were treated with application of 5% ibuprofen. Evaluation of anti-inflammatory activity was performed by determination of dynamic change of thickness and volume of affected animal limb for carrageenan-induced inflammation for 8 days (with daily registration of records), and for AITC induced inflammation for 24 h (with registration of records after 30 min, 1 h, 2 h, 3 h, 6 h and 24 h since phlogogen was introduced). Results: Flavonoids content in C. aegagropila extract varied depending on ethanol concentration: usage of 40% ethanol led to 18.2 mg of flavonoid recovery on 1.0 g of dry raw material; 70% ethanol – 39.5 mg and 96% ethanol – 35.5 mg. Therapy of 5% ointment based on C. aegagropila extract decreased inflammatory response caused by the subplantar introduction of the corresponding phlogogen. Conclusion: The ointment from C. aegagropila extract shows anti-inflammatory activity by inhibiting inflammation caused by AITC and carrageenan.

Nowadays, a significant number of antiepileptic drugs aimed at influencing the main inhibitory transmitter – gamma-aminobutyric acid (GABA). Compounds with various chemical structures, binding to different GABAA sites, potentiate the action of amino acid. Recent studies have reported that terpenoids such as l-menthone and its derivatives were found to act as modulators of GABAA receptors, thereby demonstrating anticonvulsant activity. On the other hand, neuroprotective and anticonvulsant potentialities were revealed in phenoxyacetic acid derivatives. Based on the foregoing, the combination of l-menthone and phenoxyacetic acid residues into one molecule is feasible for obtaining the pharmacological agents with antiseizure action. In order to achieve the above-mentioned goal, l-menthone hydrazones were synthesized via condensation of terpenoid with 4-R-phenoxyacetic acid hydrazides in the presence of a catalytic amount of glacial acetic acid. The structure of the target compounds has been established by FTIR-ATR, Raman, 1H-NMR and 13C-NMR spectral analysis and EI/FAB/ESI mass spectrometry. Thermal properties of hydrazones were elucidated by DSC and their purity ‒ by HPLC coupled to mass spectrometry. Synthesized compounds were found to exist as Z/E geometrical isomers about C=N bond and cis/trans amide conformers. At the present study, the influence of obtained derivatives on the central nervous system was reliably confirmed by evaluating their anticonvulsant activity. The present findings indicate that all aforementioned compounds possess antiseizure action after oral administration on PTZ-induced convulsion and maximal electroshock-induced (MES) seizures.