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101.
Kyle W. Hukari Kamlesh D. Patel Ronald F. Renzi Jay A. A. West 《Electrophoresis》2010,31(16):2804-2812
Rapid and specific characterization of bacterial endospores is dependent on the ability to rupture the cell wall to enable analysis of the intracellular components. In particular, bacterial spores from the bacillus genus are inherently robust and very difficult to lyze or solubilize. Standard protocols for spore inactivation include chemical treatment, sonication, pressure, and thermal lysis. Although these protocols are effective for the inactivation of these agents, they are less well suited for sample preparation for analysis using proteomic and genomic approaches. To overcome this difficulty, we have designed a simple capillary device to perform thermal lysis of bacterial spores. Using this device, we were able to super heat (195°C) an ethylene glycol lysis buffer to perform rapid flow‐through rupture and solubilization of bacterial endospores. We demonstrated that the lysates from this preparation method are compatible with CGE as well as DNA amplification analysis. We further demonstrated the flow‐through lysing device could be directly coupled to a miniaturized electrophoresis instrument for integrated sample preparation and analysis. In this arrangement, we were enabled to perform sample lysis, fluorescent dye labeling, and protein electrophoresis analysis of bacterial spores in less than 10 min. The described sample preparation device is rapid, simple, inexpensive, and easily integratable with various microfluidic devices. 相似文献
102.
Marta Sanz-Solé 《Journal of Functional Analysis》2008,255(1):255-281
We consider a stochastic wave equation in space dimension three driven by a noise white in time and with an absolutely continuous correlation measure given by the product of a smooth function and a Riesz kernel. Let pt,x(y) be the density of the law of the solution u(t,x) of such an equation at points (t,x)∈]0,T]×R3. We prove that the mapping (t,x)?pt,x(y) owns the same regularity as the sample paths of the process {u(t,x),(t,x)∈]0,T]×R3} established in [R.C. Dalang, M. Sanz-Solé, Hölder-Sobolev regularity of the solution to the stochastic wave equation in dimension three, Mem. Amer. Math. Soc., in press]. The proof relies on Malliavin calculus and more explicitly, the integration by parts formula of [S. Watanabe, Lectures on Stochastic Differential Equations and Malliavin Calculus, Tata Inst. Fund. Res./Springer-Verlag, Bombay, 1984] and estimates derived from it. 相似文献
103.
A. Viña Orjales M. I. Turnes Carou M. C. Prieto Blanco P. López Mahía S. Muniategui Lorenzo D. Prada Rodríguez 《Chromatographia》2000,51(1-2):77-82
Summary A systematic investigation of operational buffer systems, sample preparation and instrument parameters for achieving the best
possible performance for determinating an homologous series of N-benzyl-N-alkyl-N,N-dimethylammonium chloride compounds by
capillary zone electrophoresis with direct UV detection. The most effective separation was achieved within 3.5 min with the
addition of acetonitrile (40%) in a phosphate buffer (20 mM pH 5.2) using a 40 cm fused-silica capillary operating at 25 KV
and 20°C. Degassing of all electrolyte solutions and samples was very important. The linearity and repeatability for each
compounds were satisfactory. To improve detection limits, on-column sample preconcentration, sample stacking, was investigated
achieving a tenfold enrichment factor and quantitation limits about 10−7M. 相似文献
104.
Improvements in the Multiplex Sample NMR method are investigated to explore its capabilities of analyzing multiple samples simultaneously. Issues of quantitation and resolution in the multiple-coil probe are examined in one- and two-dimensional experiments. Improvements in quantitation are shown to result from the use of reference deconvolution for one-dimensional experiments, while the use of two-dimensional methods has much improved resolution and shows the potential for significantly increased parallelism. A multiplicative scheme is shown to be an easily implemented, effective method for generating individual sub-spectra from individual samples. 相似文献
105.
Equations have been derived to predict the extent to which the sample size may be increased, without decreasing the column performance, by stationary-phase focusing at sub-ambient temperatures. Under favorable circumstances the sample size may be enhanced several hundredfold. 相似文献
106.
In this work the Couette cell is compared with a more recently constructed disk shear cell. There are distinct advantages
of the disk over the Couette cell, in particular, when it comes to the determination of the intensity along certain Bragg
rods.
Received: 12 December 2000 Accepted: 31 January 2001 相似文献
107.
Stavroula Rozou Panayiotis Raftopoulos Sophia Hatziantoniou Ekaterini Antoniadou‐Vyza 《Journal of separation science》2009,32(20):3521-3528
Molecular inclusion of guest molecules within CDs is known to alter guest molecule spectrophotometric absorptivity, making their determination, based on spectrophotometric data, inaccurate. Therefore specific analytical methods capable of quantifying the drugs as free molecules must be developed and validated. SPE was selected to simplify sample and avoid more time‐consuming alternatives. A new solid phase was synthesized and characterized by infrared spectrometry, differential scanning calorimetry and elemental analysis. The competitive complexation of adamantane groups immobilized on the silica substrate facilitates drug:CD complex dissociation and elimination of CD from samples. The drug molecules, now free from CD, can be easily analysed by an already available HPLC method. This new SPE loading material was employed in the determination of ketoprofen in its CD complex as a representative example of the utility of this novel material. The calculated analytical errors were reduced from a maximum of 20.79% (without SPE) to a minimum of 3.99%. 相似文献
108.
109.
The effect of the solute sample size on the measurement of temperature-programmed retention indices (ITP) has been studied on glass capillary columns with different stationary phases, film thicknesses, and temperature programs. The sample capacity of a solute is little affected by the parameters of temperature program, i. e. initial temperature and heating rate. However, it has been found that in a temperature programmed run, allowable sample sizes for high ITP values are lower than for low ITP values. About 10 ng of each compound is recommended as the sample size for accurate measurement of ITP values on commonly used capillary columns. 相似文献
110.
Wei Wang 《Operations Research Letters》2008,36(5):515-519
We propose a sample average approximation (SAA) method for stochastic programming problems with expected value constraints. Such problems arise, for example, in portfolio selection with constraints on conditional value-at-risk (CVaR). We provide a convergence analysis and a statistical validation scheme for the proposed method. 相似文献