Key Role of the Oxidized Citrate-Free Radical in the Nucleation Mechanism of the Metal Nanoparticle Turkevich Synthesis

2019 ◽  
Vol 123 (36) ◽  
pp. 22624-22633 ◽  
Author(s):  
Sarah Al Gharib ◽  
Jean-Louis Marignier ◽  
Abdel Karim El Omar ◽  
Adnan Naja ◽  
Sophie Le Caer ◽  
...  
2012 ◽  
Vol 1 (10) ◽  
pp. 79 ◽  
Author(s):  
G. Raja* ◽  
Ivvala Anand Shaker ◽  
Inampudi Sailaja ◽  
R. Swaminathan ◽  
S. Saleem Basha ◽  
...  

Natural antioxidants can protect the human body from free radicals and retard the progress of many chronic diseases as well as lipid oxidative rancidity in foods. The role of antioxidants has protected effect against free radical damage that may cause many diseases including cancer. Primary sources of naturally occurring antioxidants are known as whole grains, fruits, and vegetables. Several studies suggest that regular consumption of nuts, mostly walnuts, may have beneficial effects against oxidative stress mediated diseases such as cardiovascular disease and cancer. The role of antioxidants has attracted much interest with respect to their protective effect against free radical damage that may cause many diseases including cancer. Juglans regia L. (walnut) contains antioxidant compounds, which are thought to contribute to their biological properties. Polyphenols, flavonoids and flavonols concentrations and antioxidant activity of Leaves, Stems and Nuts extract of Juglans regia L. as evaluated using DPPH, ABTS, Nitric acid, hydroxyl and superoxide radical scavenging activity, lipid peroxidation and total oxidation activity were determined. The antioxidant activities of Leaves, Stems and Nuts extract of Juglans regia L. were concentration dependent in different experimental models and it was observed that free radicals were scavenged by the test compounds in all the models.


Polymers ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 2349
Author(s):  
Alain Salvador Conejo-Dávila ◽  
Marco Armando Moya-Quevedo ◽  
David Chávez-Flores ◽  
Alejandro Vega-Rios ◽  
Erasto Armando Zaragoza-Contreras

The development of anilinium 2-acrylamide-2-methyl-1-propanesulfonate (Ani-AMPS) monomer, confirmed by 1H NMR, 13C NMR, and FTIR, is systematically studied. Ani-AMPS contains two polymerizable functional groups, so it was submitted to selective polymerization either by free-radical or oxidative polymerization. Therefore, poly(anilinium 2-acrylamide-2-methyl-1-propanesulfonic) [Poly(Ani-AMPS)] and polyaniline doped with 2-acrylamide-2-methyl-1-propanesulfonic acid [PAni-AMPS] can be obtained. First, the acrylamide polymer, poly(Ani-AMPS), favored the π-stacking of the anilinium group produced by the inter- and intra-molecular interactions and was studied utilizing 1H NMR, 13C NMR, FTIR, and UV-Vis-NIR. Furthermore, poly(Ani-AMPS) fluorescence shows quenching in the presence of Fe2+ and Fe3+ in the emission spectrum at 347 nm. In contrast, the typical behavior of polyaniline is observed in the cyclic voltammetry analysis for PAni-AMPS. The optical properties also show a significant change at pH 4.4. The PAni-AMPS structure was corroborated through FTIR, while the thermal properties and morphology were analyzed utilizing TGA, DSC (except PAni-AMPS), and FESEM.


2021 ◽  
pp. 1-11
Author(s):  
Xin Chen ◽  
Xuan Li ◽  
Xiaodong Xu ◽  
Luxiao Li ◽  
Ningning Liang ◽  
...  

2020 ◽  
Vol 10 (01) ◽  
pp. e104-e109
Author(s):  
Antonio Molina-Carballo ◽  
Antonio Emilio Jerez-Calero ◽  
Antonio Muñoz-Hoyos

AbstractMelatonin, produced in every cell that possesses mitochondria, acts as an endogenous free radical scavenger, and improves energetic metabolism and immune function, by complex molecular crosstalk with other intracellular compounds. There is greatly increasing evidence regarding beneficial effects of acute and chronic administration of high melatonin doses, in infectious, developmental, and degenerative pathologies, as an endothelial cell and every cell protectant.


2014 ◽  
Vol 18 (4 (72)) ◽  
Author(s):  
D. A. Zadyraka ◽  
E. V. Riabokon

The paper shows, that patients with purulent meningitis on the background of severe clinical and laboratory changes had a disturbance of prooxidant-antioxidant regulation with a shift towards activation of free radical oxidation. In the dynamics of the disease, after 7-10 days of conventional treatment, against the background of a reduction of cephalic and meningeal syndromes intensity, a normalization of liquor and hemogram indices, in most patients there was a further decrease in catalase activity and an increase of nitrites, of parameters of spontaneous and induced oxidative modification of blood proteins that remained when the patients were discharged, compared with healthy people.


2018 ◽  
Vol 5 (1) ◽  
pp. 96-102 ◽  
Author(s):  
Carolyn M. Wilke ◽  
Jean-François Gaillard ◽  
Kimberly A. Gray

Light influences chemical interactions of engineered nanomaterials and their toxic effects. Under simulated solar irradiation, we observed that binary mixtures of n-Ag, n-Au, or n-Pt with n-TiO2cause synergistic toxic effects inE. colidue to photochemical interactions governed by metal nanoparticle stability and localized surface plasmon resonance.


2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Ken Shinmura

The biology of aging has not been fully clarified, but the free radical theory of aging is one of the strongest aging theories proposed to date. The free radical theory has been expanded to the oxidative stress theory, in which mitochondria play a central role in the development of the aging process because of their critical roles in bioenergetics, oxidant production, and regulation of cell death. A decline in cardiac mitochondrial function associated with the accumulation of oxidative damage might be responsible, at least in part, for the decline in cardiac performance with age. In contrast, lifelong caloric restriction can attenuate functional decline with age, delay the onset of morbidity, and extend lifespan in various species. The effect of caloric restriction appears to be related to a reduction in cellular damage induced by reactive oxygen species. There is increasing evidence that sirtuins play an essential role in the reduction of mitochondrial oxidative stress during caloric restriction. We speculate that cardiac sirtuins attenuate the accumulation of oxidative damage associated with age by modifying specific mitochondrial proteins posttranscriptionally. Therefore, the distinct role of each sirtuin in the heart subjected to caloric restriction should be clarified to translate sirtuin biology into clinical practice.


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