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911.
912.
913.
914.
A novel, highly sensitive technology for the detection, enrichment, and separation of trace amounts of target DNA was developed
on the basis of amino-modified fluorescent magnetic composite nanoparticles (AFMN). In this study, the positively charged
amino-modified composite nanoparticles conjugate with the negatively charged capture DNA through electrostatic binding. The
optimal combination of AFMN and capture DNA was measured by dynamic light scattering (DLS) and UV–vis absorption spectroscopy.
The highly sensitive detection of trace amounts of target DNA was achieved through enrichment by means of AFMN. The detection
limit for target DNA is 0.4 pM, which could be further improved by using a more powerful magnet. Because of their different
melting temperatures, single-base mismatched target DNA could be separated from perfectly complementary target DNA. In addition,
the photoluminescence (PL) signals of perfectly complementary target DNA and single-base mismatched DNA as well as the hybridization
kinetics of different concentrations of target DNA at different reaction times have also been studied. Most importantly, the
detection, enrichment, and separation ability of AFMN was further verified with milk. Simple and satisfactory results were
obtained, which show the great potential in the fields of mutation identification and clinical diagnosis. 相似文献
915.
A novel molecular switch, 7-(N,N-diethylamino)-2-oxo-2H-chromen-4-yl ferrocene carboxylate (FCC), was synthesized and fully
characterized by 1H NMR, 13C NMR, and HRMS. Taking advantage of the properties of ferrocene as an electron donor active unit and the coumarin as a fluorescent
unit, the dyad FCC shows a fast and reversible redox-switchable fluorescence emission. In sharp contrast to most photoluminescent
chromophores, FCC has a unique enhanced emission through aggregation. The change of electrochemical signals (CV and DPV) indicated
that the ferrocene (Fc) unit of FCC could form inclusion complex with Me-β-cyclodextrin (CD). This inclusion complex could further weaken the aggregation-induced emission (AIE) effect remarkably.
This advance paves the way to introduce AIE property into molecular devices applications. 相似文献
916.
E. J. Gao Y. X. Zhang M. C. Zhu H. Y. Liu Y. Huang M. Zhang M. Su M. J. Guo F. Guan X. N. Gao M. L. Wang 《Russian Journal of Coordination Chemistry》2010,36(11):853-858
The complex [Pd(Bipy)2](Bpcc) · 11H2O has been synthesized and characterized (Bipy = 2,2′-bipyridyl, H2Bpcc = 4,4′-biphenylcarboxylic acid). The supramolecular architecture was constructed through hydrogen bonding and π-π-stacking. The Pd atom is four-coordinated and forms a distorted square geometry. The free H2O molecules form 1D infinite zigzag chains of water cluster, while the water cluster and Bpcc2? form an organic-water framework. 相似文献
917.
Dapsens PY Hakim SH Su BL Shanks BH 《Chemical communications (Cambridge, England)》2010,46(47):8980-8982
The current work presents an unprecedented direct observation of macropore formation in the spontaneous self-assembly process to obtain hierarchical meso/macroporous metal oxides made possible with the help of an unusual titanium alkoxide. 相似文献
918.
Su‐Kyung Lee Kyong‐Soon Shin Dr. Dong‐Youn Noh Prof. Dr. Olivier Jeannin Dr. Frédéric Barrière Dr. Jean‐François Bergamini Dr. Marc Fourmigué Dr. 《化学:亚洲杂志》2010,5(1):169-176
The redox‐active and chelating diphosphine, 3,4‐dimethyl‐3′,4′‐bis(diphenylphosphino)‐tetrathiafulvalene, denoted as P2 , is engaged in a series of platinum complexes, [(P2)Pt(dithiolene)], with different dithiolate ligands, such as 1,2‐benzenedithiolate (bdt), 1,3‐dithiole‐2‐thione‐4,5‐dithiolate (dmit), and 5,6‐dihydro‐1,4‐dithiin‐2,3‐dithiolate (dddt). The complexes are structurally characterized by X‐ray diffraction, together with a model compound derived from bis(diphenylphosphino)ethane, namely, [(dppe)Pt(dddt)] . Four successive reversible electron‐transfer processes are found for the [(P2)Pt(dddt)] complex, associated with the two covalently linked but electronically uncoupled electrophores, that is, the TTF core and the platinum dithiolene moiety. The assignments of the different redox processes to either one or the other electrophore is made thanks to the electrochemical properties of the model compound [(dppe)Pt(dddt)] lacking the TTF redox core, and with the help of theoretical calculations (DFT) to understand the nature and energy of the frontier orbitals of the [(P2)Pt(dithiolene)] complexes in their different oxidation states. The first oxidation of the highly electron‐rich [(P2)Pt(dddt)] complex can be unambiguously assigned to the redox process affecting the Pt(dddt) moiety rather than the TTF core, a rare example in the coordination chemistry of tetrathiafulvalenes acting as ligands. 相似文献
919.
Lei H Wang Y Su C Liang F Su W Hui M Shaw P Luo Y 《Natural product communications》2010,5(10):1673-1676
The essential oils from leaves, twigs and stems of large trees and shrub-like trees of Thuja sutchuenensis were extracted by hydrodistillation and supercritical fluid extraction, and analyzed by GC and GC-MS. The essential oil composition differed significantly among the three organs, as well as between large trees and shrub-like trees. Furthermore, consistent with the eastern Asia-North American disjunct distribution of the genus, many differences in the essential oil composition between T. sutchuenensis and other Thuja species were apparent. The essential oils exhibited a certain degree of antifungal activity against six strains of human pathogenic fungi. 相似文献
920.
T. Y. Wu M. H. Tsao F. L. Chen S. G. Su C. W. Chang H. P. Wang Y. C. Lin I. W. Sun 《Journal of the Iranian Chemical Society》2010,7(3):707-720
A series of new organic dyes comprising carbazole, iminodibenzyl, and phenothiazine moieties as the electron donors and rhodanine ring as the electron acceptor/anchoring groups were designed and developed for use in dye-sensitized solar cells. HOMO and LUMO energy level tuning was achieved by varying the carbazole, iminodibenzyls and phenothiazine donors. This was evidenced by spectral and electrochemical experiments and density functional theory calculations. Electrochemical studies indicated that the phenothiazine unit was much more effective in lowering the ionization potential than were the iminodibenzyl and carbazole units. The phenothiazine dye shows a solar-energy-to-electricity conversion efficiency (η) of 4.87%; the carbazole and iminodibenzyl dyes show η of 2.54% and 3.52%, respectively. These findings reveal that using carbazole, iminodibenzyl and phenothiazine donors as light-harvesting sensitizers are promising candidates for dye-sensitized solar cells. 相似文献