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201.
202.
Kok Whye Cheong Hamed Mirhosseini Bahareh Tabatabaee Amid Nazimah Sheikh Abdul Hamid 《Journal of Dispersion Science and Technology》2018,39(7):934-942
The physicochemical properties of soursop beverage emulsion were investigated using mixture design. Results indicated that the regression models were significantly fitted for all response variables studied, except creaming index at 10°C. Interactions between biopolymers and oil phase had the most significant effect on creaming stability; however, modified starch played a much prominent role in maintaining the cloudiness and average droplet size. Meanwhile, WPI contributed significantly to the conductivity of the emulsions. The optimum condition resulted in desirable physicochemical properties could be achieved using 8.70% (w/w) modified starch, 1.02% (w/w) WPI, 10.11% (w/w) flavor oil, and 76.57% (w/w) water. 相似文献
203.
204.
Sonia Sheikh Christophe Blaszykowski Michael Thompson 《Surface and interface analysis : SIA》2013,45(11-12):1781-1784
This follow‐up study describes the implementation of recently developed cross‐linking trichlorosilane surface chemistry with acoustic wave sensing technology for the real‐time and label‐free detection of biotin/avidin interactions. Biosensing platforms consist of unelectroded piezoelectric quartz resonator discs onto which functionalizable mixed organosilane adlayers are prepared using a new trichlorosilane cross‐linker in combination with a shorter monofunctional diluent molecule. Thiolated or aminated biotin probes can next be anchored to the mixed assembly in a single, preactivation‐free step through site‐specific coupling at pentafluorophenyl ester head moieties. Biosensing properties are assessed at ultra‐high frequency (>0.74 GHz) with the highly sensitive electromagnetic piezoelectric acoustic sensor using micromolar buffered solutions of avidin. This biosensor prototype – which generally displays good reproducibility – uses sacrificial bovine serum albumin to block non‐specific adsorption. This preliminary work in buffer constitutes an important step towards the development of real‐world biosensors able to perform with more demanding biological samples. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
205.
Berrin Ozcelik Javed Sheikh Ilkay E. Orhan Harjeet Juneja Brahim Bennani Abdelali Kerbal S. M. T. Cavalcanti Ana C. L. Leite Taibi Ben Hadda 《Research on Chemical Intermediates》2013,39(7):2955-2962
Conformational restriction constitutes a useful strategy of molecular modification for the design of new potential drug candidates. Herein we present the planning, antimicrobial evaluation, and establishment of structure–activity relationship (SAR) data for some isoxazole (3a–k, 8a–c, and 9a–c) and pyrazole (5a–h) derivatives. These derivatives were structurally designed by conformational restriction followed by bioisosteric exchange of previously described antimicrobial isoquinolines (1a–c). Some of these more conformationally restricted derivatives present improved properties as new antibacterial drug candidates. 相似文献
206.
Yeasmin S Kim CH Park HJ Sheikh MI Lee JY Kim JW Back KK Kim SH 《Applied biochemistry and biotechnology》2011,164(3):294-304
Cellulase-free xylanase has potential for its application in the selective removal of hemicellulose from kraft pulp to give
good strength to paper. In this study, a gene (xyn) encoding cellulase activity–free xylanase enzyme (Xyn) was isolated from Paenibacillus polymyxa PPL-3. The xyn gene encoded a protein of 221 amino acids, and the purified Xyn was about 22.5 kDa measured by sodium dodecyl sulfate–polyacrylamide
gel electrophoresis. Moreover, the cellulase activity–free xylanase enzyme (Xyn) was displayed on the cell surface of Saccharomyces cerevisiae EBY100 using Aga2p as an anchor protein. Cell surface display of xylanase enzyme (Xyn) on S. cerevisiae EBY100 was confirmed by immunofluorescence microscopy. Optimum cell surface display of xylanase enzyme (Xyn) was observed
at pH 7 and 40 °C. Therefore, cell surface–displayed xylanase enzyme (Xyn) can be used in the paper industry. 相似文献
207.
Sheikh KH Giordani C Kilpatrick JI Jarvis SP 《Langmuir : the ACS journal of surfaces and colloids》2011,27(7):3749-3753
Supported dipalmitoylphosphatidylcholine (DPPC) bilayers are widely used membrane systems in biophysical and biochemical studies. Previously, short-range positional and orientational order of lipid headgroups of supported DPPC bilayers was observed at room temperature using low deflection noise frequency modulation atomic force microscopy (FM-AFM). While this ordering was supported by X-ray diffraction studies, it conflicted with diffusion coefficient measurements of gel-phase bilayers determined from fluorescence photobleaching experiments. In this work, we have directly imaged mica-supported DPPC bilayers with submolecular resolution over scan ranges up to 146 nm using low deflection noise FM-AFM. Both orientational and positional molecular ordering were observed in the mesoscale, indicative of crystalline order. We discuss these results in relation to previous biophysical studies and propose that the mica support induces mesoscopic crystalline order of the DPPC bilayer at room temperature. This study also demonstrates the recent advance in the scan range of submolecular scale AFM imaging. 相似文献
208.
Mohamed Habila Bushra Alhenaki Adel El‐Marghany Mohamed Sheikh Ayman Ghfar Zeid ALOthman Mustafa Soylak 《Journal of separation science》2020,43(15):3103-3109
Metal organic frameworks are considered as an efficient and promised adsorbent for separation of several ions and compounds from solutions due to its unique geometric structure. Herein, copper‐benzyl tricarboxylic acid based metal organic frameworks have showed a high efficiency in enrichment and microextraction of malathion from food and water samples. The microextraction procedures were followed by determination of malathion by ultra high performance liquid chromatography with tandem mass spectrometry. The optimum recoveries for malathion were obtained at pH 6, and with using 2 mL of ethyl acetate as the eluent. The microextraction procedures showed a detection limits and the quantification limits of 4.0 and 10.0 µg/L, respectively. The intra‐ and interday precision showed a relative standard deviation% less than 10. The feasibility of the proposed procedure was determined by evaluating the addition/recovery studies of malathion from the real samples. The absolute recovery% was ≥92%. Furthermore, some ions were tested as cointerfering ions, and the recovery% was 93‐100%. These results confirm that the developed microextraction procedure based on copper‐benzyl tricarboxylic acid based metal organic frameworks as extractor for dispersive solid phase microextraction is matrix‐independent, and can be applied for various real samples including different matrix or various malathion content. 相似文献
209.
Habibul Arfin Jagjit Kaur Tariq Sheikh Sudip Chakraborty Angshuman Nag 《Angewandte Chemie (International ed. in English)》2020,59(28):11307-11311
Bi3+ and lanthanide ions have been codoped in metal oxides as optical sensitizers and emitters. But such codoping is not known in typical semiconductors such as Si, GaAs, and CdSe. Metal halide perovskite with coordination number 6 provides an opportunity to codope Bi3+ and lanthanide ions. Codoping of Bi3+ and Ln3+ (Ln=Er and Yb) in Cs2AgInCl6 double perovskite is presented. Bi3+‐Er3+ codoped Cs2AgInCl6 shows Er3+ f‐electron emission at 1540 nm (suitable for low‐loss optical communication). Bi3+ codoping decreases the excitation (absorption) energy, such that the samples can be excited with ca. 370 nm light. At that excitation, Bi3+‐Er3+ codoped Cs2AgInCl6 shows ca. 45 times higher emission intensity compared to the Er3+ doped Cs2AgInCl6. Similar results are also observed in Bi3+‐Yb3+ codoped sample emitting at 994 nm. A combination of temperature‐dependent (5.7 K to 423 K) photoluminescence and calculations is used to understand the optical sensitization and emission processes. 相似文献
210.
Research and development in the design, synthesis, modification, evaluation, and characterization of polysaccharide‐based bioactive polymeric materials for guiding and promoting new tissue in‐growth is reviewed. Emphasis is given in this interdisciplinary field of tissue engineering (TE) with particular reference to bone, cartilage, and skin TE. Current strategies in scaffold‐guided TE approaches using polymers of natural origin and their composites are elaborated. Innovative modification techniques in creating functional materials for advanced TE applications are presented. Challenges and possible solutions in the technological innovation in factor molecules incorporation and surface functionalization for improving the fabrication of biomaterials scaffolds for cost‐effective TE are also presented.