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981.
Muhammad Najam‐ul‐Haq Adeela Saeed Fahmida Jabeen Dilshad Hussain Naseem Khan Maryam Shabir Nadeem Raza Muhammad Naeem Ashiq Muhammad Aslam Malana Zafar Iqbal Zafar 《Biomedical chromatography : BMC》2015,29(7):981-989
Determination of the availability of phases for specific separations is an important task achieved by a separation chemist. This becomes vital when the complex samples like biofluids are dealt with in proteome science. The work presented here involves the synthesis and application of terpolymeric sorbent with different functionalizations adopted for the selective enrichment of biomolecules of interest from biological fluids. Synthesis of terpolymer was carried out by the radical polymerization of monomers: methyl acrylate, acrylic acid and vinyl acetate with diethylene glycol dimethacrylate as cross‐linking agent, benzoyl peroxide as initiator and chloroform as a porogenic solvent. Characterization was done through Fourier transform infrared spectroscopy, scanning electron microscopy and nitrogen adsorption porosimetry. The polymer was further modified to immobilized metal ion affinity chromatographic material, with immobilized Fe3+/La3+ ions that allowed phosphopeptide enrichment from tryptic digests of standard proteins as well as milk, egg yolk and human serum. Sensitivity of enrichment down to 50 fmol was achieved in the presence of complex protein background as bovine serum albumin. Hydrophobicity was introduced through octadecyl amine, which provides comparable results to ZipTip C18/C4 for desalting of complex mixtures of all caseins. Analysis of the enriched content was performed by Matrix Assisted Laser Desorption Ionization Mass Spectrometry (MALDI‐MS). Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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984.
Purusottam-Reddy B. Sivajee-Ganesh K. Jayanth-Babu K. Hussain O. M. Julien C. M. 《Ionics》2015,21(8):2319-2328
Ionics - We prepared copper oxide thin films as electrode of supercapacitors. Films of Cu–O were grown by rf-magnetron sputtering on stainless steel substrates maintained at... 相似文献
985.
Ismail B. Onajobi Shabbir Hussain Kulsoom Javaid Obasola E. Fagade I. A. Oladosu 《Natural product research》2016,30(22):2507-2513
Two new 10-hydroxy-9(10H)-anthracenone, madagascenone A (1) and B (2), were isolated from the barks of Harungana madagascariensis Lam. The structures of the compounds were determined using 1D- and 2D-NMR and mass spectroscopic techniques. Both of the compounds showed an in vitro α-glucosidase inhibition with IC50 = 69.9 ± 4.21 and 122.3 ± 1.13 μM, respectively, more potent than the standard acarbose (IC50 = 840 ± 1.23 μM). 相似文献
986.
Ferrocene conjugated copper(II) complexes of terpyridine and traditional Chinese medicine (TCM) anticancer ligands showing selective toxicity towards cancer cells 下载免费PDF全文
Banashree Deka Arnab Bhattacharyya Sanjoy Mukherjee Tukki Sarkar Kiran Soni Samya Banerjee Kandarpa K. Saikia Sasanka Deka Akhtar Hussain 《应用有机金属化学》2018,32(4)
Six novel mixed‐ligand copper(II) complexes, namely, [Cu(R‐tpy)(L)]NO3 ( 1–6 ), where R‐tpy is 4′‐phenyl‐2,2′:6′,2′′‐terpyridine (Ph‐tpy; 1–3 ) and 4′‐ferrocenyl‐2,2′:6′,2′′‐terpyridine (Fc‐tpy; 4–6 ), L is the bidentate O,O donor monoanion of plumbagin (5‐hydroxy‐2‐methyl‐1,4‐naphthoquinone; plum in 1 , 4 ), chrysin (5,7‐dihydroxyflavone; chry in 2 , 5 ) and curcumin (bis(4‐hydroxy‐3‐methoxyphenyl)‐1,6‐diene‐3,5‐dione; curc in 3 , 6 ) have been synthesized and characterized and their in vitro cytotoxicity against cancer cells is evaluated. The energy optimized structures and the frontier orbitals of the complexes have been obtained from the DFT calculations. Complexes 4–6 with a conjugated ferrocenyl moiety and TCM anticancer ligands, namely, plum (in 4 ), chry (in 5 ) and curc (in 6 ) showed potent cytotoxicity giving respective IC50 values of 1.2 μM, 0.62 μM and 0.21 μM in HeLa and 2.0 μM and 1.0 μM and 0.34 μM in MCF‐7 cancer cells while being much less toxic to MCF‐10A normal cells (IC50: 8.3‐17.1 μM). In contrast, complexes 1–3 with a conjugated phenyl moiety were appreciably less toxic to HeLa cells with respective IC50 values of 10.4 μM, 8.1 μM and 5.5 μM when compared with their ferrocenyl analogues 4–6 . Mechanistic studies using Hoechst staining and Annexin‐V‐FITC assays on cancer cells revealed an apoptotic pathway of cell death induced by the complexes. Fluorescence imaging study showed that complex 6 having curcumin as ligand localized primarily in the mitochondria of HeLa cells. Thus, we demonstrate in this study that ferrocene conjugation to copper(II) complexes of TCM anticancer ligands significantly increases the selectivity and cytotoxicity of the resulting complexes towards cancer cells over normal cells. 相似文献
987.
G. Hussain A. Hameed J. G. Hetherington A. Q. Malik K. Sanaullah 《Journal of Applied Mechanics and Technical Physics》2013,54(1):10-20
Hydrocode simulations are carried out using Ansys Autodyn (version 11.0) to study the effects of the liner material (mild steel, copper, armco iron, tantalum, and aluminum) on the shape, velocity, traveled distance, pressure, internal energy, temperature, divergence or stability, density, compression, and length-to-diameter ratio of explosively formed projectiles. These parameters are determined at the instants of the maximum as well as stable velocity during the flight towards the target. The results of these parameters present the potential capability of each liner material used to fabricate explosively formed projectiles. An experimental analysis is performed to study the velocity status and the length-to-diameter ratio of explosively formed projectiles. 相似文献
988.
Fazli Khuda Zafar Iqbal Yasar Shah Muhammad Abbas Zakiullah Muhammad Hassan 《Chromatographia》2016,79(9-10):655-655
989.
M. Naveen Ch. Upendar Reddy Md. Manzoor Hussain M. Chaitanya Golla Narayanaswamy 《Journal of heterocyclic chemistry》2013,50(5):1064-1066
Efficient method for the total synthesis of egonol in five steps via Sonogashira coupling reaction is reported. 相似文献
990.
M. Zafar Iqbal M. Abdul Qadir 《International journal of environmental analytical chemistry》2013,93(4):533-538
Abstract The determination of Pb and Cd in three different kinds of biological tissues, namely Sapindus mukorossis, Alstonia scholaris and Diospyros embryopteris collected from a national city park were carried out using atomic absorption spectrophotometry. The various tissues contain different concentrations of Pb and Cd. This phenomenon and changes in concentration with the distance to the sampling sites are discussed and compared with values reported in literature. Significant pollution is mainly due to vehicle exhaust. 相似文献