Anton V. Lobanov

The aim of the study is to comparatively analyze the reparative properties of chlorophyll (Chl), the active ingredient in nettle extract, and hemin in free and polymeric forms, using an experimental incised wound model. The experiment was designed to study wound regeneration by secondary intention. The study was conducted on white, nonlinear mice matched for similar weight, age, and gender and quarantined for 7 days. Wound area was analyzed, and the regeneration process was monitored. Therapy began on the first postoperative day. 200 μl of the preparations were applied daily. The animals' general condition, motor activity, and wound surface condition were assessed by phases of progression (inflammation, regeneration, and epithelialization) using the planimetric method proposed by J.I. Kundin. Polymeric forms of Chl and hemin induced high-quality tissue reparation, shortening the regeneration time. A high degree of reparation was observed in the 1st and 3rd experimental groups, with normotrophic healing. A moderate degree of healing was observed in the 2nd and 4th groups. On the 7th day, the 1st group showed the most intense reduction in wound surface area of all experimental groups – 47 %. In the 2nd experimental group, wound area decreased by 43.6 %, with wounds without eschar formation and low granulation. In the third experimental group of mice, an increase in wound surface area by 14 % (within the error limit) was observed. In the fourth experimental group, a significant decrease in wound surface area was 6.6 %. By day 21, the wound surface of mice in both experimental groups had completely epithelialized. Polymeric forms of Chl and hemin demonstrated high regenerative activity in this experiment. The obtained data suggest their potential use in the treatment of farm animals.

This work is devoted to the electrospinning of biocompatible fibrous matrixes for microbial wound therapy. The problem of treating staphylococcal-infected wounds remains urgent. In this study, we propose a new approach to the use of the chlorophyll (Chl) and poly-3-hydroxybutyrate (PHB) composite system in the treatment of infected wounds. The structure and properties of the electrospun polymer matrix based on PHB modified with various concentrations of Chl was investigated by SEM, confocal microscopy, DSC, EPR. The release rate, fluorescence, and antimicrobial activity of Chl incorporated into PHB were studied. The high efficiency of the developed materials was shown with the participation of laboratory animals.

An Erratum to this paper has been published: https://doi.org/10.1134/S1990793124330029

The possibility of using radiation from a two-frequency pulsed copper vapor laser with wavelengths of 510.6 nm and 578.2 nm with an exposure of 30 to 120 s to stimulate the development of coniferous trees (spruce, pine, larch) with a single seed irradiation is shown. The stimulation effect manifests itself at various early stages of development, such as the awakening of seeds in the aquatic environment in the first hours of the experiment (according to electron absorption spectroscopy data), seed germination, and seedling growth under stressful cultivation conditions. Possible causes of light exposure to plant seeds are discussed.

The possibility of using radiation from a two-frequency pulsed copper vapor laser with wavelengths of 510.6 and 578.2 nm with an exposure of 30 to 120 s to stimulate the development of coniferous trees (spruce, pine, larch) with single seed irradiation is shown. The stimulation effect manifests itself at various early stages of development, such as the awakening of seeds in the aquatic environment in the first hours of the experiment (according to the electron absorption spectroscopy data), seed germination, and seedling growth under stressful cultivation conditions. Possible causes of light exposure to plant seeds are discussed.

Разработана технология получения пектина, включающая стадии экстрагирования пектинсодержащего (яблочного) сырья смесью кислот, фильтрации и выделения пектина из водно-изопропиловой смеси. Установлено, что высушенный пектин имеет массовую долю влаги 4,7 %. С помощью метода ИК-спектроскопии подтверждено наличие метоксилированных карбоксильных групп. Показано, что водный раствор пектина в смеси с сахарозой и лимонной кислотой образует устойчивую гелеобразную систему, а также установлена степень этерификации – 71%, соответствующая высокоэтерифицированному пектину. Раствор микрогеля (6%-ый) эффективно сорбирует ионы Cu2+ в первые секунды после смешения, через 40 мин концентрация Cu2+ в растворе уменьшается в ~3,3 раза. Анализ размеров частиц микрогеля показал образование частиц со средним диаметром около 70 нм, в то время как после сорбции Cu2+ эта величина возросла до 3350 нм. Величина ζ-потенциала изменялась с -20 до +1,56 мВ после сорбции Cu2+. A technology for the production of pectin has been developed, including the stages of extraction of pectin-containing (apple) raw materials with a mixture of acids, filtration and isolation of pectin from an aqueous-isopropyl mixture. It was found that dried pectin has a mass fraction of 4.7% moisture. the presence of methoxylated carboxyl groups was confirmed by IR spectroscopy. An aqueous solution of pectin mixed with sucrose and citric acid forms a stable gel-like system, and the degree of esterification was established – 71%, corresponding to highly esterified pectin. A 6% microgel solution effectively sorbs Cu2+ in the first seconds after mixing, after 40 min the concentration of Cu2+ in the solution decreases ~3.3 times. Microgel particle size analysis showed the formation of particles with an average diameter of about 70 nm, while after Cu2+ sorption this value increased to 3350 nm. The value of the zeta potential changed from -20 to +1.56 mV after Cu2+ sorption.

Показано, что мономолекулярный слой тетрафенилпорфирина в смеси со стеариновой кислотой, перенесенный на модифицированные кварцевые пластины, проявляет флуоресцентные свойства, чувствительные к присутствию катионов европия(III) в водных средах. Предложен сенсорный элемент для количественного определения европия в воде и определены его рабочие параметры. Monomolecular layer of tetraphenylporphyrin mixed with stearic acid transferred onto modified quartz plates is shown to exhibit fluorescent properties sensitive to the presence of europium(III) cations in aqueous media. A principal possibility of producing a sensor element for quantitative determination of europium in water is proposed, and its performance parameters are determined.

Предложена процедура безотходного получения в лабораторных условиях гидроксиапатита (ГАП) медицинского и биологического назначения, предназначенного для изготовления костных имплантатов. Способ состоит из двух стадий: синтеза ГАП в роторно-пульсационном аппарате ионообменным способом, что обеспечивает полноту синтеза и наноразмеры частиц, и стадии последующей очистки продукта. Ключевым моментом разработанной процедуры является дальнейшая утилизация образующихся на стадии очистки промывных вод, которые могут быть использованы как минеральный комплекс, обогащенный азотом, фосфором и кальцием, для подкормки сельскохозяйственных растений. Показано, что полученный минеральный комплекс способствует ускоренному росту растений в агрессивных почвах. A procedure has been proposed for non-waste laboratory-scale production of hydroxyapatite (HAP) which can be applied for medical use, i.e. for manufacturing bone implants. The procedure involves 2 steps: synthesis of HAP in a rotary pulsation apparatus by ion-exchange method providing sufficiently good yields of nano-scale particles followed by subsequent purification of the product. The key point of the developed procedure is further utilization of the wash waters from the purification step with their use as a mineral complex additive enriched with nitrogen, phosphorus, and calcium for feeding agricultural plants. It has been demonstrated that the resulting mineral complex contributes to the accelerated growth of plants in aggressive soils.

The nature of frontier molecular orbitals in complexes of phthalocyanines with p-, d0-, and d10-elements (magnesium, zinc, aluminum, gallium, and silicon) has been established by means of...

Tetrapyrrolic macrocyclic compounds and their metal complexes are an important class of coordination compounds widely applied for development of materials with a broad range of functional properties, for example, highly sensitive redox systems for monitoring potentially toxic objects in solutions, or biocidal agents possessing an activity against pathogenic microorganisms, etc. The paper presents results of studying photocatalytic activity of silica immobilized metal-tetrapyrrole (i.e. tetraphenylporphyrin, phthalocyanine, and chlorophyll) complexes in hydrogen peroxide decomposition reaction. A linear correlation has been established between the photocatalytic activity of a number of p -, d0 -, and d10 -metal complexes of the studied macrocycles in the decomposition of hydrogen peroxide and their ability to generate a photopotential. These photophysical and photochemical characteristics are interrelated and can be used for evaluation and prediction of each other. In addition, the examined systems can be considered as a special treatment tool for destroying hazardous chemical compounds or harmful biological structures. Тетрапиррольные макроциклические соединения и их металлокомплексы являются важным классом координационных соединений, используемых для разработки материалов с широким спектром функциональных свойств, например, высокочувствительных сенсорных редокс-систем для мониторинга потенциально опасных объектов в растворах, или биоцидных материалов, активных в отношении патогенных микроорганизмов и др. В статье представлены результаты исследования фотокаталитической активности иммобилизованных на силикагелевой подложке металлокомплексов тетрафенилпорфирина, фталоцианина и хлорофилла в процессе разложения пероксида водорода. Установлена линейная корреляция между фотокаталитической активностью ряда p -, d0 - и d10 -металлокомплексов изученных макроциклов в разложении пероксида водорода и их способностью генерировать фотопотенциал. Эти свойства взаимосвязаны и могут быть использованы для оценки и предсказания друг друга. Кроме того, изученные системы могут рассматриваться как бинарные агенты для деструкции опасных химических веществ и биологических объектов.