Co-reporter:Huami Ming, Manli Wang, Hongzong Yin
Analytical Biochemistry 2015 Volume 468() pp:59-65
Publication Date(Web):1 January 2015
DOI:10.1016/j.ab.2014.09.014
Abstract
Two novel surface plasmon resonance immunosensors were fabricated for detection of the Bacillus thuringiensis Cry1Ab protein and to demonstrate their performance in analyzing Cry1Ab protein in crop samples. Sensor 2 was modified by 1,6-hexanedithiol, Au/Ag alloy nanoparticles, 3-mercaptopropionic acid, and protein A (or not [sensor 1]), with Cry1Ab monoclonal antibody. As a result, both of the immunosensors exhibited satisfactory linear responses in the Cry1Ab protein concentration ranges of 10 to 500 ng ml−1 and 8 to 1000 ng ml−1, and the detection limits were 5.0 and 4.8 ng ml−1, respectively. The immunosensors possessed good specificity and acceptable reproducibility. In addition, crop samples could be analyzed after a simple treatment. The transgenic crops could be easily identified from the conventional ones by the two immunosensors.
Co-reporter:Qingxi Meng;Fen Wang
Journal of Physical Organic Chemistry 2015 Volume 28( Issue 6) pp:431-436
Publication Date(Web):
DOI:10.1002/poc.3432
Density functional theory (DFT) was used to investigate computationally cobalt(I)-catalyzed hydroacylation of vinylsilanes and alkyl aldehydes to give ketones. Calculation indicated that cobalt(I)-catalyzed hydroacylation had eight possible reaction pathways. In the cobalt-hydride complexes IM2a and IM2b, the hydrogen migration occurred prior to the carbon–carbon bond-forming reaction. In the complexes IM3a1 and IM3b1, the carbonyl elimination reaction occurred prior to the direct reductive elimination reaction. In the cobalt–carbonyl complexes IM4a and IM4b, the carbonyl insertion reaction was much easier to achieve than the decarbonylation reaction. The dominant reaction pathway was the reaction channel IM1a TS1a IM2a TS2a1 IM3a1 TS4a IM4a TS5a IM5a TS6a IM6a, and the reductive elimination reaction was the rate-determining step for this channel, so the dominant product predicted theoretically was the linear ketone. Furthermore, the solvation effect was remarkable, and it decreased generally the free energies of the species. Copyright © 2015 John Wiley & Sons, Ltd.
Co-reporter:Fen Wang;Shuhua Zhu;Qingxi Meng
Journal of Molecular Modeling 2015 Volume 21( Issue 8) pp:
Publication Date(Web):2015 August
DOI:10.1007/s00894-015-2754-6
Density functional theory (DFT) was used to investigate nickel-catalyzed ring-opening hydroacylation of methylenecyclopropanes and benzaldehydes. The results indicated that the Ni-P(n-Bu)3 complex exhibited much more excellent catalysis than the other two complexes (Ni-PMe3 and Ni-P(t-Bu)3). The hydrogen migration was the rate-determining step, and the β-carbon elimination was the chirality-limiting step. The dominant product was a (S,S)- cis ketone. The phosphine ligand P(n-Bu)3 changed the rate-determining step, and greatly decreased the free energies of the rate-determining step and chirality-limiting step. The use of P(n-Bu)3 generally decreased the free energies of the intermediates and transition states. The possible role of P(n-Bu)3 was the transformation of the electron and geometry structures of those intermediates and transition states.
Co-reporter:Chao Zhang, Yong-Hua Qi, Ping Qian, Ming-Jing Zhong, Liang Wang, Hong-Zong Yin
Computational and Theoretical Chemistry 2014 Volume 1046() pp:10-19
Publication Date(Web):15 October 2014
DOI:10.1016/j.comptc.2014.07.004
•Cluster models Si6O18H12 and Al6O24H30 for kaolinite surfaces are constructed.•Various gas state properties of all systems are systematically explored.•The Al–O/water system is more stable than the Si–O/water system.•The order of intensity of H-bonds is Water/Water > Water/Al–O > Water/Si–O.Kaolinite is a kind of layered aluminosilicate showing a large variety of physicochemical properties. In this research, various gas phase properties of interactions between the Si–O layer (Si6O18H12) or Al–O layer (Al6O24H30) cluster model of kaolinite and n water molecules (n = 1–3) have been systematically explored at the B3LYP [Becke’s three-parameter hybrid exchange functional (B3) and the correlation functional of Lee, Yang, and Parr (LYP)] level using the 6-31G(d) basis set. These gas phase properties include optimal structures, structural parameters, hydrogen bonds, interaction energies, natural bond orbital charge distributions, vibration frequencies, electron density characteristics and maps of electronic potential. The most stable structures of each system have been obtained when one, two and three water molecules are adsorbed on each surface. With an increasing number of water molecules, there are also hydrogen bonds between water molecules besides the hydrogen bonds between water and the kaolinite surface. The results show that the stabilization of hydrogen bonds is closely connected with the kaolinite surface type, surface structure, and position and orientation towards the surface of water molecules. Moreover, the Al–O/water system is more stable than the Si–O/water system. Simultaneously, the hydrogen bonds formed between water molecules are the strongest, followed by those between water and the Al–O layer and lastly those between water and the Si–O layer.
Co-reporter:Kunyou Zhan, Kun Xu, Hongzong Yin
Food Chemistry 2011 Volume 126(Issue 4) pp:1959-1963
Publication Date(Web):15 June 2011
DOI:10.1016/j.foodchem.2010.12.052
A novel method for purifying gingerols from ginger was developed using a high-speed counter-current chromatography (HSCCC). The two-phase solvent system such as light petroleum (bp 60–90 °C)–ethyl acetate–methanol–water (5:5:6.5:3.5, v/v/v/v) was applied to the separation and purification of 6-, 8- and 10-gingerol from a crude extract of ginger. The experiment yielded 30.2 mg of 6-gingerol, 40.5 mg of 8-gingerol, 50.5 mg of 10-gingerol from 200 mg of crude extract in one-step separation. And the purity of these compounds was 99.9%, 99.9% and 99.2%, respectively, as determined by high-performance liquid chromatography (HPLC). Their structures were identified by gas chromatography–mass spectrometry (GC/MS) and 1H, 13C nuclear magnetic resonance (NMR).Research highlights► The conventional procedure for purifying gingerols from ginger was time-consuming, expensive and low efficient. ► Therefore, some alternative strategies were needed urgently. ► A novel method for purifying gingerols from ginger was developed using a high-speed counter-current chromatography (HSCCC). ► Gingerols with high purity may be used for in vitro and in vivo studies and as reference substances for analytical purposes.
Co-reporter:Weihong SONG;Xiaoxiao ZHANG;Panpan SA ;Xiaoyan LIU
Chinese Journal of Chemistry 2009 Volume 27( Issue 4) pp:717-721
Publication Date(Web):
DOI:10.1002/cjoc.200990118
Abstract
Silver nanoparticles were obtained by a chemical reduction method using aqueous polymers as dispersant and characterized by UV-Vis spectroscopy, transmission electron microscopy (TEM) and light-scattering spectroscopy. Solid polymer films containing the silver nanoparticles were also prepared after evaporating the solvent, and then dried with existing polymer. The stability of the silver nanoparticles was compared between primary fresh silver nanoparticle solution and redissolved solid polymer films by UV-Vis spectroscopy. The particle size ranged from 5 to 10 nm, and no obvious differences were found. Therefore, preparing solid nano-Ag/polymer was a novel and useful method in storage of silver nanoparticles.
