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991.
Maha M. Abdelrahman Neven M. Habib Aml A. Emam Hamada M. Mahmoud Nada S. Abdelwhab 《Biomedical chromatography : BMC》2020,34(4):e4804
Green TLC-densitometric and RP-HPLC methods were developed and validated for the determination of the active prodrug sulfasalazine (SZ), its active metabolite mesalazine (MZ) and the major active metabolite of mesalazine, N-acetyl-5-aminosalicylic acid (AS). In the developed TLC-densitometric method, chromatographic separation was carried out on TLC silica gel plates 60 F254 using a developing system consisting of ethyl acetate–methanol–ammonia solution 33% (8:2.5:0.3, by volume) and then scanning the separated bands at 215 nm using hydrochlorothiazide as an internal standard with linearity ranges of 0.4–3, 0.4–2.4 and 0.3–2 for SZ, MZ and AS, respectively. The developed RP-HPLC method depended on chromatographic separation using a C18 column with a solvent mixture of methanol–aqueous acetic acid solution (pH 5) as a mobile phase with gradient elution mode and UV scanning at 243 nm using pyrazinamide as internal standard with linearity ranges of 5–50, 5–40, and 3–20 for SZ, MZ and AS, respectively. US Food and Drug Administration guidelines were followed during validation of the methods. The greenness of the developed methods was estimated using the greenness profile and the Eco-Scale approach. Both methods passed the four quadrants of the greenness profile and had Eco-Scale score ˃75, thus they were considered to be green according to these approaches. 相似文献
992.
Physics of Atomic Nuclei - In this work we derive analytically a real $$\alpha+\alpha$$ potential using the JLM effective nucleon–nucleon (NN) interaction. The aim is to obtain analytically... 相似文献
993.
Ezzat Hany G. Bayoumi Ashraf H. Sherbiny Farag F. El-Morsy Ahmed M. Ghiaty Adel Alswah Mohamed Abulkhair Hamada S. 《Molecular diversity》2021,25(1):291-306
Molecular Diversity - Many shreds of evidence have recently correlated A2B receptor antagonism with anticancer activity. Hence, the search for an efficient A2B antagonist may help in the... 相似文献
994.
Hussain Shafqat Öztop Hakan F. Mehmood Khalid Ali Mohamed E. 《Journal of Thermal Analysis and Calorimetry》2019,137(5):1735-1755
Journal of Thermal Analysis and Calorimetry - A computational analysis has been performed to study the impact of magnetic field on entropy generation due to mixed convective nanofluid flow with top... 相似文献
995.
996.
Elsayed Abd El-Rahman Shilkamy Hoda A. El-Shafy Elrouby Mahmoud 《Journal of Solid State Electrochemistry》2021,25(8):2161-2174
Journal of Solid State Electrochemistry - Zinc metal is an important element that can be used for long-life alkaline batteries. In this work, it is found that the addition of minor amounts of... 相似文献
997.
998.
Novel Schiff base ligand based on the condensation of 4,6-diacetyl resorcinol with 2-amino-4-methylthiazole in addition to its metal complexes with Cr (III), Mn (II), Fe (III), Co (II), Ni (II), Cu (II), Zn (II) and Cd (II) ions have been synthesized. The structure, electronic properties, and thermal behaviour of Schiff base and its metal complexes have been studied by elemental analysis, mass, 1H NMR, IR spectra, thermal analysis, and theoretically by density function theory. The ligand acted as mononegative bidentate (NO) ligand and all complexes showed octahedral geometry except Cu (II) showed tetrahedral geometry as indicated from the spectral and magnetic studies. The Cu (II), Zn (II) and Cd (II) complexes were non electrolytes while the rest of the complexes were electrolytes. The antibacterial plus anticancer activities of the parent Schiff base and its metal complexes were screened. In addition, the molecular docking study was performed to explore the possible ways for binding to Crystal Structure of Human Astrovirus capsid protein (5ibv) receptor. 相似文献
999.
Isomotive dielectrophoresis (isoDEP) is a unique DEP geometrical configuration where the gradient of the field-squared () is constant. IsoDEP analyzes polarizable particles based on their magnitude and direction of translation. Particle translation is a function of the polarizability of both the particles and suspending medium, the particles’ size and shape, and the frequency of the electric field. However, other electrokinetics act on the particles simultaneously, including electrothermal hydrodynamics. Hence, to maximize the DEP force relative to over electrokinetic forces, design parameters such as microchannel geometry, fabrication materials, and applied electric field must be properly tuned. In this work, scaling law analyses were developed to derive design rules, relative to particle diameter, to reduce unwanted electrothermal hydrodynamics relative to DEP-induced particle translation. For a particle suspended in 10 mS/m media, if the channel width and height are below ten particle diameters, the electrothermal-driven flow is reduced by ∼500 times compared to a channel that is 250 particles diameters in width and height. Replacing glass with silicon as the device's underlying substrate for an insulative-based isoDEP reduces the electrothermal induced flow approximately 20 times less. 相似文献
1000.
A novel Schiff base namely (E)-3-((2,6-dihydroxypyrimidin-4-ylimino)methyl)-4H-chromen-4-one and its Co (II), N (II)i, Cu (II) and Cd (II) complexes have been synthesized and proved by elemental analysis, molar conductance, thermal analysis (TGA), Inductive Coupled plasma (ICP), magnetic moment measurements, X-ray powder diffraction, IR, EI-mass,1H NMR, 13C NMR,UV–Vis. and ESR spectral studies. On the basis of these data, it is evident that the Schiff base acts as bidentate via oxygen atom of carbonyl group and azomethine nitrogen atom for Co (II) complex; monobasic bidentate ligand for Ni (II), Cu (II) and Cd (II) complexes via oxygen atom of hydroxyl group and nitrogen atom of pyrimidine ring. The results showed all complexes have octahedral geometry. The average particle size of the ligand and its complexes were found to be 1.010–0.343 nm. The pharmacological action (antioxidant, antimicrobial and anticancer) of the prepared compounds is studied. The antitumor activity of the ligand and its metal complexes is evaluated against human liver carcinoma (HEPG2) cell. The data displayed the Co (II) complexes strong cytotoxicity where IC50 values of Co (II) complex and 5-fluorouracil (stander drug) are 9.33 and 7.86 μg/ml respectively. The Co (II) and Cd (II) complexes have antibacterial activity more than ampicillin (stander drug). The interaction of the synthesized compounds with calf-thymus DNA (CT-DNA) has been performed via absorption spectra and viscosity technique. The DNA- binding constants have been determined. 相似文献