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991.
Nehal F. Farid Ibrahim A. Naguib Nessreen S. Abdelhamid Basma H. Anwar Maimana A. Magdy 《Journal of separation science》2020,43(12):2330-2337
A novel ecofriendly, cost and time saving high‐performance thin‐layer chromatographic method was developed and validated for simultaneous determination of metoclopramide, ergotamine, caffeine, and paracetamol in bulk and pharmaceutical formulation. The separation was carried out on silica gel plates, using ethyl acetate:ethanol:ammonia (9:1:0.1, v/v/v) as a developing system. Ultraviolet detection was carried out at 272 nm. The resulting retention times were 0.15, 0.36, 0.49, and 0.74 min for metoclopramide, ergotamine, caffeine, and paracetamol, respectively. The greenness profile assessment was achieved to the proposed method to evaluate its greenness characters to the environment with acceptable results. Validation parameters were checked according to International Conference of Harmonization guidelines to achieve the international requirements for quality control analysis of the proposed drugs. 相似文献
992.
Xiaoli Liu Michelle M. T. Jansman Peter W. Thulstrup Ana C. Mendes Ioannis S. Chronakis Leticia Hosta‐Rigau 《Macromolecular bioscience》2020,20(2)
Despite all the attempts to create advanced hemoglobin (Hb)‐based oxygen carriers (HBOCs) employing an encapsulation platform, major challenges including attaining a high Hb loading and long circulation times still need to be overcome. Herein, the fabrication, for the first time, of nanoparticles fully made of Hb (Hb‐NPs) employing the electrospray technique is reported. The Hb‐NPs are then coated by antioxidant and self‐polymerized poly(dopamine) (PDA) to minimize the conversion of Hb into nonfunctional methemoglobin (metHb). The PDA shell is further functionalized with poly(ethylene glycol) (PEG) to achieve stealth properties. The results demonstrate that the as‐prepared Hb‐NPs are hemo‐ and biocompatible while offering antioxidant protection and decreasing the formation of metHb. Additionally, decoration with PEG results in decreased protein adsorption onto the Hb‐NPs surface, suggesting a prolonged retention time within the body. Finally, the Hb‐NPs also preserve the reversible oxygen‐binding and releasing properties of Hb. All in all, within this study, a novel HBOCs with high Hb content is fabricated and its potential as an artificial blood substitute is evaluated. 相似文献
993.
Dmitri V. Konarev Aleksey V. Kuzmin Salavat S. Khasanov Alexander F. Shestakov Akihiro Otsuka Hideki Yamochi Hiroshi Kitagawa Rimma N. Lyubovskaya 《化学:亚洲杂志》2020,15(17):2689-2695
Two salts of the aromatic hydrocarbon decacyclene, {cryptand[2.2.2](Cs+)} (decacyclene.?) ( 1 ) and {Bu3MeP+}(decacyclene.?) ( 2 ), were obtained. In both salts, decacyclene.? radical anions formed channels occupied by cations. However, corrugated hexagonal decacyclene.? layers could be outlined in the crystal structure of 1 with several side‐by‐side C???C approaches. The decacyclene.? radical anions showed strong distortion in both salts, deviating from the C3 symmetry owing to the repulsion of closely arranged hydrogen atoms and the Jahn‐Teller effect. Radical anions showed intense unusually low energy absorption in the IR‐range, with maxima at 4800 and 6000 cm?1. According to the carculations, these bands can originate from the SOMO‐LUMO+1 and SOMO‐LUMO+2 transitions, respectively. Radical anions exhibited a S=1/2 spin state, with an effective magnetic moment of 1.72 μB at 300 K. The decacyclene.? spin antiferromagnetically coupled with a Weiss temperature of ?11 K. Spin ordering was not observed down to 1.9 K owing to spin frustration in the hexagonal decacyclene.? layers. 相似文献
994.
Bilkan M. T. Alyar S. Alyar H. 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2020,94(1):143-151
Russian Journal of Physical Chemistry A - In this paper, two new Schiff bases (L1 and L2) derived from substituted salicylaldehyde and sulfamethoxazole/sulfisoxazole were synthesized. The... 相似文献
995.
Kuzina S. I. Bol’shakov A. I. Kulikov A. V. Mikhailov A. I. 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2020,94(1):189-195
Russian Journal of Physical Chemistry A - The photolysis of dry benzoyl peroxide (BP) at 77 K in the 480–236 nm range of wavelengths and an ethanol solution is studied via EPR. It is... 相似文献
996.
997.
Gupta M. Kulriya P. K. Kumar R. Ghumman S. S. 《Journal of Radioanalytical and Nuclear Chemistry》2020,323(3):1413-1418
Journal of Radioanalytical and Nuclear Chemistry - Zirconolite, a potential candidate for the immobilization of actinides was investigated for the induced effects of α-particles simulated... 相似文献
998.
Hristozova G. Marinova S. Svozilík V. Nekhoroshkov P. Frontasyeva M. V. 《Journal of Radioanalytical and Nuclear Chemistry》2020,323(2):839-849
Journal of Radioanalytical and Nuclear Chemistry - In the most recent 2015/2016 campaign of the European-scale moss survey, Bulgaria joined for the fifth consecutive time. To investigate elemental... 相似文献
999.
Dey Chaudhuri S. Banerjee D. Bhattacharjee T. Wasim Raja Sk Acharya R. Pujari P. K. 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(2):829-835
Journal of Radioanalytical and Nuclear Chemistry - Performance of 1″?×?1″ LaBr3 (5% Ce) scintillator coupled to Hamamatsu R2083 PM Tube has been investigated for the... 相似文献
1000.