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71.
A practical approach to screen for authorised and unauthorised genetically modified plants 总被引:4,自引:0,他引:4
Hans-Ulrich Waiblinger Lutz Grohmann Joachim Mankertz Dirk Engelbert Klaus Pietsch 《Analytical and bioanalytical chemistry》2010,396(6):2065-2072
In routine analysis, screening methods based on real-time PCR are most commonly used for the detection of genetically modified
(GM) plant material in food and feed. In this paper, it is shown that the combination of five DNA target sequences can be
used as a universal screening approach for at least 81 GM plant events authorised or unauthorised for placing on the market
and described in publicly available databases. Except for maize event LY038, soybean events DP-305423 and BPS-CV127-9 and
cotton event 281-24-236 × 3006-210-23, at least one of the five genetic elements has been inserted in these GM plants and
is targeted by this screening approach. For the detection of these sequences, fully validated real-time PCR methods have been
selected. A screening table is presented that describes the presence or absence of the target sequences for most of the listed
GM plants. These data have been verified either theoretically according to available databases or experimentally using available
reference materials. The screening table will be updated regularly by a network of German enforcement laboratories. 相似文献
72.
Summary: The effect of sodium dodecyl sulfate (SDS) on the mass transfer rate between styrene and water has been investigated. SDS increases the solubility of styrene in water even below the critical micelle concentration (CMC) and therefore increases the thermodynamic driving force for the mass transfer. The mass transfer coefficient however is not altered by SDS, even if the interface is almost saturated with emulsifier. 相似文献
73.
Aebischer OF Aebischer A Tondo P Alameddine B Dadras M Güdel HU Jenny TA 《Chemical communications (Cambridge, England)》2006,(40):4221-4223
The self-assembled architectures in solution of a new HBC derivative bearing perfluoroalkylated side chains were investigated by optical excitation and emission spectroscopy and correlated to cryo-SEM, a new technique in organic chemistry. 相似文献
74.
Schnitzler MC Mangrich AS Macedo WA Ardisson JD Zarbin AJ 《Inorganic chemistry》2006,45(26):10642-10650
This work reports the incorporation of ferrocene into a porous silica glass under ambient temperature and atmosphere. After or during the ferrocene incorporation, the spontaneous formation of ferricinium ions was observed by electron paramagnetic resonance (EPR), UV-visible, X-ray absorption near-edge structure (XANES), and 57Fe M?ssbauer measurements. It was shown that the oxidation of ferrocene molecules to ferricinium ions was promoted by air and that the Si-O- groups on the surface of the pores act as counteranions. Pyrolysis of the porous glass/ferricinium material under argon atmosphere and variable temperature yields different glass/carbon nanocomposites, which were subsequently treated with an HF solution in order to remove the glassy fraction. The resulting insoluble carbon materials were characterized by transmission electron microscopy (TEM), Raman, and EPR spectroscopy and consisted of amorphous carbon when the pyrolysis was carried out at 900 or 1000 degrees C and of a mixture of carbon nanotubes and carbonaceous materials at a pyrolysis temperature of 1100 degrees C. When the pyrolysis was conducted under air, the incorporated ferricinium forms alpha-Fe2O3, and the resulting material is a transparent and highly homogeneous glass/iron oxide nanocomposite. 相似文献
75.
[reaction: see text] An efficient approach to the azaspirane core of FR 901483 is described employing lithiated methoxyallene as a crucial C3 building block and a suitably protected enantiopure ketimine as the second component. The resulting dihydropyrrole derivative was smoothly converted into a spiro keto aldehyde which under acidic conditions provided a novel azanorbornane derivative 15. Under basic reaction conditions, the desired 5-azatricyclo[6.3.1.0(1,5)]dodecane skeleton 16 was generated. The ratio of diastereomers strongly depends on the reaction conditions employed with l-proline in DMSO providing the highest selectivity in favor of one azaspirane product. 相似文献
76.
Matthias Lotz Benoît Pugin Martin Kesselgruber Marc Thommen Felix Spindler Hans-Ulrich Blaser Andreas Pfaltz Marc Schoenleber 《Tetrahedron: Asymmetry》2010,21(9-10):1199-1202
The bis(2-methoxymethyl pyrrolidine)phosphine moiety is shown to be a very effective chiral auxiliary for the ortho- and diastereoselective lithiation of ferrocene, thereby allowing the highly selective attachment of various electrophiles to the cyclopentadienyl ring of ferrocene. The potential of the methodology is demonstrated by the synthesis of Kephos, a new family of ferrocenyl diphosphines and of OH-Taniaphos derivatives. 相似文献
77.
78.
A surprising samarium diiodide-induced coupling reaction of carbonyl compounds with methoxyallene provided 4-hydroxy 1-enol ethers, which are versatile synthetic building blocks. In this coupling reaction, methoxyallene serves as an acrolein equivalent, which cannot directly be employed. [reaction: see text] 相似文献
79.
Blaser HU 《Chemical communications (Cambridge, England)》2003,(3):293-296
The application of enantioselective catalysis to the fine chemicals industry has great potential both from economic and ecological points of view, but to date has not been widely implemented on a technical scale. The author hopes that the award of the 2001 Chemistry Nobel Prize in this field will give the necessary impetus to future applications. 相似文献
80.