scholarly journals A study on the biological activity of biosynthesized nanoparticles of metal oxides

Author(s):  
A M Korotkova ◽  
O B Polivanova ◽  
I A Gavrish ◽  
M Y Koroleva ◽  
E N Baranova ◽  
...  
Langmuir ◽  
2010 ◽  
Vol 26 (22) ◽  
pp. 16652-16657 ◽  
Author(s):  
K. Y. Niu ◽  
J. Yang ◽  
S. A. Kulinich ◽  
J. Sun ◽  
X. W. Du

2012 ◽  
Vol 66 (5) ◽  
Author(s):  
Mária Omastová ◽  
Matej Mičušík

AbstractPolypyrrole is one of the most frequently studied conducting polymers, having high electrical conductivity and stability, suitable for multi-functionalised applications. Coatings of chemically synthesised polypyrrole applied onto various organic and inorganic materials, such as polymer particles and films, nanoparticles of metal oxides, clay minerals, and carbon nanotubes are reviewed in this paper. Its primary subject is the formation of new materials and their application in which chemical oxidative polymerisation of pyrrole was used. These combined materials are used in antistatic applications, such as anti-corrosion coating, radiation-shielding, but also as new categories of sensors, batteries, and components for organic electronics are created by coating substrates with conducting polymer layers or imprinting technologies.


Metals ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 80
Author(s):  
Mir Sayed Shah Danish ◽  
Liezel L. Estrella ◽  
Ivy Michelle A. Alemaida ◽  
Anton Lisin ◽  
Nikita Moiseev ◽  
...  

Along with industrialization and rapid urbanization, environmental remediation is globally a perpetual concept to deliver a sustainable environment. Various organic and inorganic wastes from industries and domestic homes are released into water systems. These wastes carry contaminants with detrimental effects on the environment. Consequently, there is an urgent need for an appropriate wastewater treatment technology for the effective decontamination of our water systems. One promising approach is employing nanoparticles of metal oxides as photocatalysts for the degradation of these water pollutants. Transition metal oxides and their composites exhibit excellent photocatalytic activities and along show favorable characteristics like non-toxicity and stability that also make them useful in a wide range of applications. This study discusses some characteristics of metal oxides and briefly outlined their various applications. It focuses on the metal oxides TiO2, ZnO, WO3, CuO, and Cu2O, which are the most common and recognized to be cost-effective, stable, efficient, and most of all, environmentally friendly for a sustainable approach for environmental remediation. Meanwhile, this study highlights the photocatalytic activities of these metal oxides, recent developments, challenges, and modifications made on these metal oxides to overcome their limitations and maximize their performance in the photodegradation of pollutants.


2020 ◽  
Vol 158 ◽  
pp. 104715
Author(s):  
Janaina Rodrigues Fernandes ◽  
Lídia Pereira Amaro ◽  
Edvani Curti Muniz ◽  
Silvia Luciana Favaro ◽  
Eduardo Radovanovic

2019 ◽  
Vol 2019 ◽  
pp. 1-31 ◽  
Author(s):  
Tetiana A. Dontsova ◽  
Svitlana V. Nahirniak ◽  
Ihor M. Astrelin

The features of the properties and creation of nanocomposite metal oxide materials, especially TiO2, ZnO, SnO2, ZrO2, and Fe3O4, and their applications for ecology are considered in the article. It is shown that nanomaterials based on them are very promising for use in the ecological direction, especially as sorbents, photocatalysts, and sensitive layers of gas sensors. The crystallochemical characteristics, surface structure, and surface phenomena that occur when they enter the water and air environment are given for these metal oxides, and it is shown that they play a significant role in obtaining the sorption and catalytic characteristics of these nanomaterials. Particular attention is paid to the dispersion and morphology of metal oxide particles by which their physical and chemical properties can be controlled. Synthesis methods of metal oxide nanomaterials and ways for creating of nanocomposites based on them are characterized, and it is noted that there are many methods for obtaining individual nanoparticles of metal oxides with certain properties. The main task is the correct selection and testing of parameters. The prospects for the production of metal oxide nanocomposites and their application for environmental applications are noted, which will lead to a fundamentally new class of materials and new environmental technologies with their participation.


Author(s):  
S.D. Polischuk ◽  
G.I. Churilov ◽  
D.G. Churilov ◽  
V.V. Churilova ◽  
I.S. Arapov ◽  
...  

Биологическая активность наночастиц зависит от физико-химических характеристик частиц. Химическое взаимодействие наночастиц с жидкой средой, по-нашему мнению, является одним из определяющих факторов их биологической активности. Изменение рН среды за счет высокой восстановительной способности наночастиц повышает проницаемость мембран, способствуя биоаккумуляции наночастиц или усилению их биосовместимости. Данная способность зависит от той информации (тех свойств), которой обладают частицы разных размеров, состава и физико-химических характеристик. Высокой биологической активностью обладают наночастицы металлов железа, кобальта, меди размером 35-60 нм в количестве 0,01-10,0 г на тонну семян, полученные низкотемпературной металлизацией нанодисперсных порошков гидроксидов. Наночастицы оксидов металлов размером 20-80 нм снижают рост и развитие растений, и в отличие от наночастиц металлов, они аккумулируются в структурах растений, понижая активность фитогормонов и ферментов. При этом аномальная дозовая зависимость эффекта в области сверхнизких концентраций биологически активных веществ зарегистрирована на уровне ответа не только клетки или целостного организма (растения), но и отдельных биомакромолекул (ферментов). В наших исследованиях мы обнаружили, что всякий раз при введении сверхмалых доз биологически активного вещества в организм животного, клеточную культуру или в модельную систему, содержащую суспензиюмембран, отмечается изменение структурных характеристик мембран. В свою очередь изменения структуры мембран могут приводить к изменению функционального состояния клетки, а наличие полимодальности в ответе можно объяснить сменой механизма действия вещества в том или ином концентрационном интервале на структуру мембраныThe biological activity of nanoparticles depends on the physical-chemical characteristics of the particles. The chemical interaction of nanoparticles with a liquid medium, in our opinion, is one of the determining factors in their biological activity. A change in the pH of the medium due to the high reducing bility of nanoparticles increases the permeability of membranes, promoting bio-accumulation of nanoparticles or enhancing theirbio-compatibility. This ability depends on the information (those properties) of particles of different sizes, their composition and physical-chemical characteristics. Metal nanoparticles of iron, cobalt, copper of 35-60 nm in the amount of 0.01-10.0 g per ton of seeds, obtained by low-temperature metallization of nanodispersed hydroxide powders, possess high biological activity. Nanoparticles of metal oxides with a size of 20-80 nm reduce plant growth and development, and unlike metal nanoparticles, they accumulate in plant structures, reducing the activity of phytohormones and enzymes. In this case, an abnormal dose dependence of the effect of ultra-low concentrations of biologically active substances is recorded at the level of response not only of the cell or the whole organism (plant), but also of individual bio-macromolecules (enzymes). The studies showed that every time an ultra-low dose of a biologically active substance is introduced into an animal, a cell culture, or into a model system containing a suspension of membranes, a change in the structural characteristics of the membranes is noted. In turn, changes in the structure of membranes can lead to a change in the functional state of the cell, and the presence of polymodality in the response can be explained by a change in the mechanism of action of a substance in a particular concentration range on the membrane structure.


2021 ◽  
Vol 12 (4) ◽  
pp. 581-587
Author(s):  
O. V. Tsymbalyuk ◽  
T. L. Davydovska ◽  
A. M. Naumenko ◽  
A. N. Liashevych ◽  
I. S. Lupaina ◽  
...  

The specificities of the structure and blood supply of the uterus facilitate a considerable accumulation of nanosized xenobiotics, including nanoparticles of metal oxides, in its tissues. Numerous in vitro and in vivo experiments demonstrated that nanoparticles of metal oxides (ZnO and TiO2) have significant cytotoxic activity, caused by oxidative stress induction. However, there is no information about the impact of these nanomaterials on the functional state of the myometrium under chronic exposure on the organism. Tenzometric methods and mechanokinetic analysis were used in our work to investigate the contractile activity of the myometrium of non-pregnant rats. The contractile activity was either spontaneous or induced by oxytocin (the uterotonic hormone) and acetylcholine (the agonist of muscarinic choline receptors) under chronic peroral intake of the ZnO and TiO2 aqueous nanocolloids into the organism. It was found that after burdening of rats with ZnO and ТіО2 aqueous nanocolloids there were no changes in the pacemaker-dependent mechanisms forming the frequency of spontaneous contractions in the myometrium, but there was a considerably induced increase in the AU index of contractions. It was shown that during the oxytocin-induced excitation of the myometrium under both chronic and short-term burdening of the rats with ZnO and TiO2 aqueous nanocolloids, the mechanisms that regulate the intracellular concentration of Ca2+ ions are the target for the nanomaterials. When the rats were burdened with ZnO aqueous nanocolloids for 6 months, during cholinergic excitation there was hyperstimulation of both M3-receptor-dependent mechanisms of Са2+ ions intake via the potential-governed Са2+-channels of L-type into the smooth muscles of the myometrium, and M2-receptor-dependent mechanisms, controlling the intracellular concentration of these cations. Thus, the regularities and mechanisms of the change in the functioning of uterine smooth muscles under chronic intake of the ZnO and TiO2 aqueous nanocolloids were determined in this study.


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