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91.
M. H. Hashmi Abdus Subhan Adil N. A. Chughtai Farhat Rafique Chughtai M. A. Shahid 《Mikrochimica acta》1968,56(2):291-296
Summary A method has been developed for the separation and identification of 20 common amino acids by circular thin-layer chromatography. The amino acids are separated to neutral, acid, and basic groups by electrolysis and then identified by circular TLC. The method is simple and development of a chromatoplate is complete in about 3 minutes. The application of the method is illustrated by the analysis of amino acids in foods and in urine.
Zusammenfassung Zur Trennung und Identifizierung 20 gewöhnlicher Aminosäuren wurde ein chromatographisches Verfahren entwickelt. Die Aminosäuren werden elektrolytisch in neutrale, basische und saure getrennt und dann auf kreisförmiger Dünnschichte chromatographiert. Die Entwicklung des Chromatogramms ist in 3 Minuten beendet. Die Anwendung zur Analyse von Lebensmitteln und Harn wird beschrieben.相似文献
92.
Fused NaFeCl(4) shows a great affinity for moisture, which reacts chemically with it. By passage through a heated column filled with NaFeCl(4) coated on bioglass, gases such as nitrogen are found to have retained some moisture when dried over a molecular sieve. The compound also acts as a self-indicator, as the colour changes from yellow to brown after the reaction. It is more efficient than molecular sieves and is regenerated by passing HCl gas through the column. 相似文献
93.
94.
Munazza Raza Mirza Matthias Rainer Shahid Duran Syed Tarique Moin M. Iqbal Choudhary Günther K. Bonn 《Biomedical chromatography : BMC》2019,33(9)
A poly(dibenzo‐18‐crown‐6) was used as a new solid‐phase extraction material for the selective enrichment of phosphopeptides. Isolation of phosphopeptides was achieved based on specific ionic interactions between poly(dibenzo‐18‐crown‐6) and the phosphate group of phosphopeptides. Thus, a method was developed and optimized, including loading, washing and elution steps, for the selective enrichment of phosphopeptides. To assess this potential, tryptic digest of three proteins (α‐ casein, β‐casein and ovalbumin) was applied on poly(dibenzo‐18‐crown‐6). The nonspecific products were removed by centrifugation and washing. The spectrometric analysis was performed using matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry. Highly selective enrichment of both mono‐ and multiphosphorylated peptides was achieved using poly(dibenzo‐18‐crown‐6) as solid‐phase extraction material with minimum interference from nonspecific compounds. Furthermore, evaluation of the efficiency of the poly(dibenzo‐18‐crown‐6) was performed by applying the digest of egg white. Finally, quantum mechanical calculations were performed to calculate the binding energies to predict the affinity between poly(dibenzo‐18‐crown‐6) and various ligands. The newly identified solid‐phase extraction material was found to be a highly efficient tool for phosphopeptide recovery from tryptic digest of proteins. 相似文献
95.
An efficient synthetic method for the preparation of pyridyl‐pyrimidines as potential inhibitors of protein–protein interactions is described. The key transformation is the reaction of a pyrimidine enaminone with phenyl ethyl acetate and NH4OAc to yield the desired pyridyl‐pyrimidine. 相似文献
96.
97.
Surendra K. Gautam Dhananjai Pandey S.N. Upadhyay Shahid Anwar N.P. Lalla 《Solid State Communications》2008,146(9-10):425-427
The problem of identification of the correct crystalline structure of CdS nanoclusters below 2.5 nm in size is outlined. Structure of thiophenol capped CdS nanoclusters in the size range 1.2–4.3 nm, synthesized using cadmium acetate solution in methanol, is discussed using powder XRD and electron diffraction data. Unambiguous confirmation of the wurtzite phase in CdS nanoclusters below 2.5 nm size is reported. The observation of 102 wurtzite peak in the XRD patterns of such nanoclusters indicates low stacking fault concentration. 相似文献
98.
Lughmani Faiza Nazir Farzana Khan Shahid Ali Iqbal Mudassir 《Cellulose (London, England)》2022,29(3):1911-1928
Cellulose - In this study, microcrystalline cellulose (MCC) was modified to oxidized cellulose (OC), 6-deoxycellulose hydrazide and 6-deoxycellulose (N,N-diethyl)amine (MCC-Hyd and MCC-DEM)... 相似文献
99.
In this work, we report a novel dinuclear Sn (II) complex, [Sn2(Hpdm)2(H2O)6] 2H2O 2Cl ( 1 ) (H2pdm = pyridine‐2,6‐dimethanol), which has been crystallized out and characterized by elemental analysis, FTIR, 1H and 13C NMR, single crystal X‐ray studies and Density Functional Theory (DFT) analysis. X‐ray structure of 1 has confirmed it to be a dinuclear alkoxo‐bridged Sn (II) species where each metal adopts a seven coordinate distorted pentagonal bipyramidal (pbp) geometry. This is the first hepta‐coordinated Sn (II) complex ever isolated apart from already reported stannylenes. Spin density plots from DFT support the +2 oxidation state of each tin metal. Hirshfeld surface analysis reveals the presence of various H‐bonding interactions in the molecule and molecular docking results along with DFT confirm higher binding affinity of the present complex towards DNA. Moreover, the complex exhibits promising anticancer activities against HeLa and A549 cancer cell lines. 相似文献
100.