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71.
Luana Malacaria Giuseppina Anna Corrente Amerigo Beneduci Emilia Furia Tiziana Marino Gloria Mazzone 《Molecules (Basel, Switzerland)》2021,26(9)
This review focuses on the ability of some natural antioxidant molecules (i.e., hydroxycinnamic acids, coumarin-3-carboxylic acid, quercetin, luteolin and curcumin) to form Al(III)- and Fe(III)-complexes with the aim of evaluating the coordination properties from a combined experimental and theoretical point of view. Despite the contributions of previous studies on the chemical properties and biological activity of these metal complexes involving such natural antioxidants, further detailed relationships between the structure and properties are still required. In this context, the investigation on the coordination properties of Al(III) and Fe(III) toward these natural antioxidant molecules might deserve high interest to design water soluble molecule-based metal carriers that can improve the metal’s intake and/or its removal in living organisms. 相似文献
72.
73.
Quantitative study on La~(3+) influx mediated by sodium-calcium exchanger in human lymphocytes 总被引:2,自引:0,他引:2
Whether La3+ can enter human peripheral blood lymphocytes by the Na+/Ca2+ exchanger or not and the effect of La3+on the Na+/Ca2+ exchanger activity are examined by fura-2 technique. And that whether La3+ is sequestered by intracellular organelles (mainly endoplasmic reticulum and mitochondria) is studied by this method. La3+uptake is obviously stimulated by pre-treating the cells with ouabain and by removing extracellular Na+, and intracellular La3+concentration ([La3+]i) is directly proportional to its extracellular concentration ([La3+]o). But when [La3+]o exceeds 0.4 mmol/L, the 340/380 nm ratio of fluorescence is no longer varied and the maximum [La3+], is 1.5×10-12 mol · L-1. The higher concentration of La3+ (0.1 mmol/L) increases Na+/Ca2+ exchange-mediated calcium influx, but lower concentration (10 μmol/L) appears to block calcium influx. The results also suggest that cytosolic La3+ is transported by the ATP-dependent Ca2+ pump. Intracellular Ca2+ stores are depleted by ionomycin, and then ion 相似文献
74.
C. Martínez R. Cremer D. Neuschütz J. P. Servais D. Loison 《Surface and interface analysis : SIA》2002,34(1):524-526
The formation of oxides at the surface of Fe–1.5%Mn and Fe–0.6%Mn binary alloys was investigated as a function of the conditions of the heat treatments. Both the influence of temperature and the atmosphere under which the experiments were performed were studied. The range of annealing temperatures was adjusted to 800°C. The atmosphere consisted of a mixture of N2–5%H2 and traces of water vapour, with different fixed dew points ranging from −10°C to −30°C. The state of the annealed surfaces was determined using in situ analytical devices attached to the annealing reactor in order to avoid surface contamination or the formation of native oxides after the experiments due to contact with air. The structure and composition of the surfaces were determined by reflection high-energy electron diffraction (RHEED) and electron spectroscopy (XPS, AES). Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
75.
In this study, batch experiments were conducted to investigate the performance of microscale Fe/Cu bimetallic particles-air-persulfate system (mFe/Cu-air-PS) for p-nitrophenol (PNP) treatment in aqueous solution. The results indicate that toxic and refractory PNP in aqueous solution could be decomposed effectively and transformed into lower toxicity intermediates. 相似文献
76.
Metal-organic framework MIL-100(Fe) and g-C3N4 heterojunctions (MG-x, x = 5%, 10%, 20%, and 30%, x is the mass fraction of MIL-100(Fe) in the hybrids) were facilely fabricated through ball-milling and annealing, and characterized by powder X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric analysis, transmission electron microscopy, UV-visible diffuse-reflectance spectrometry, and photoluminescence emission spectrometry. The photocatalytic activities of the series of MG-x heterojunctions toward Cr(VI) reduction and diclofenac sodium degradation were tested upon irradiation with simulated sunlight. The influence of different organic compounds (ethanol, citric acid, oxalic acid, and diclofenac sodium) as hole scavengers and the pH values (2, 3, 4, 6, and 8) on the photocatalytic activities of the series of MG-x heterojunctions was investigated. MG-20% showed superior photocatalytic Cr(VI) reduction and diclofenac sodium degradation performance than did the individual MIL-100(Fe) and g-C3N4 because of the improved separation of photoinduced electron-hole charges, which was clarified via photoluminescence emission and electrochemical data. Moreover, the MG-x exhibited good reusability and stability after several runs. 相似文献
77.
A novel turn-on rhodamine B-based fluorescent chemosensor (RBCS) was designed and synthesized by reacting N-(rhodamine B)lactam-1,2-ethylenediamine and carbon disulfide. Upon addition of Fe3+ in EtOH/H2O solution (2:1, v/v, HEPES buffer, 0.6?mM, pH 7.20), the RBCS displayed a significant fluorescence enhancement at 582?nm and a dramatic color change from colorless to pink, which can be detected by the naked eye. Significantly, the RBCS exhibited a highly selective and sensitive ability toward Fe3+. The detection limit of the probe was 2.05?×?10?7?M. Job's plot indicated the formation of 1:1 complex between the RBCS and Fe3+. Moreover, the practical use of the RBCS is demonstrated by its application in the detection of Fe3+ in HeLa cells. 相似文献
78.
Tejal Barkhade Ambadas Phatangare Shailendra Dahiwale Santosh Kumar Mahapatra Indrani Banerjee 《Surface and interface analysis : SIA》2019,51(9):894-905
The advent of nano-biotechnology has inspired the interface interaction study between engineered nanoparticles (NPs) and biomolecules. The interaction between Fe content titanium dioxide (TiO2) NPs and adenosine triphosphate (ATP) biomolecules has been envisioned. The effect of Fe content in TiO2 matrix was studied using X-ray diffraction (XRD) and transmission electron microscopy (TEM). The increase in Fe content caused a decrease in particle size with change in morphology from spherical to one-dimensional rod structure. The Fe incorporation in the TiO2 matrix reduced the transition temperature from anatase to rutile (A-R) phase along with formation of haematite phase of iron oxide at 400°C. The interaction of Fe content TiO2 NPs with ATP molecule has been studied using spectroscopic method of Raman scattering and infrared vibration spectrum along with TEM. Fe content in TiO2 has enhanced the interaction efficiency of the NPs with ATP biomolecules. Raman spectroscopy confirms that the NPs interact strongly with nitrogen (N7) site in the adenine ring of ATP biomolecule. Engineering of Fe content TiO2 NP could successfully tune the coordination between metal oxide NPs with biomolecules, which could help in designing devices for biomedical applications. 相似文献
79.
Simultaneous determination of Fe(II) and Fe(III) by kinetic spectrophotometric H-point standard addition method 总被引:1,自引:0,他引:1
The H-point standard addition method (HPSAM) for simultaneous determination of Fe(II) and Fe(III) is described. The method is based on the difference in the rate of complex formation of iron in two different oxidation states with Gallic acid (GA) at pH 5. Fe(II) and Fe(III) can be determined in the range of 0.02–4.50 μg ml−1 and 0.05–5.00 μg ml−1, respectively, with satisfactory accuracy and precision in the presence of other metal ions, which rapidly form complexes with GA under working conditions. The proposed method was successfully applied for simultaneous determination of Fe(II) and Fe(III) in several environmental and synthetic samples with different concentration ratios of Fe(II) and Fe(III). 相似文献
80.
S. Colonna S. De Rossi M. Faticanti I. Pettiti P. Porta 《Journal of molecular catalysis. A, Chemical》2002,180(1-2):161-168
ZrO2-supported La, Co oxide catalysts with different La, Co loading (2, 6, 8, 12 and 16 wt.% as LaCoO3) were prepared by impregnation of tetragonal ZrO2 with equimolar amounts of La and Co citrate precursors and calcination at 1073 K. The catalysts were characterized by X-ray diffraction (XRD), X-ray absorption spectroscopy (XAS), and BET specific surface area determination. Catalytic CO oxidation was performed at 298–800 K. XRD revealed the presence of tetragonal zirconia with traces of the monoclinic phase. LaCoO3 perovskite was also detected for loading higher than 6%. XAS experiments suggested that at high loading LaCoO3 and Co3O4 were formed, while at low loading, La, Co oxide species interacting with support, and hard to be structurally defined, prevailed. The catalysis study evidenced that the catalytic activity was due to segregated and highly dispersed cobalt oxide species. 相似文献