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Anne Tscheliessnig Danny Ong Jeremy Lee Siqi Pan Gernalia Satianegara Kornelia Schriebl Andre Choo Alois Jungbauer 《Journal of chromatography. A》2009,1216(45):7851-7864
A two-step purification strategy comprising of polyethylene glycol (PEG) precipitation and anion-exchange chromatography was developed for a panel of monoclonal immunoglobulin M (IgM) (pI 5.5–7.7) produced from hybridoma cultures. PEG precipitation was optimized with regards to concentration, pH and mixing. For anion-exchange chromatography, different resins were screened of which Fractogel EMD, a polymer grafted porous resin had the highest capacity. Despite its significantly slower mass transfer, the binding capacity was still higher compared to a convection driven resin (monolith). This purification strategy was successfully demonstrated for all 9 IgMs in the panel. In small scale most antibodies could be purified to >95% purity with the exception of two which gave a lower final purity (46% and 85%). The yield was dependent on the different antibodies ranging from 28% to 84%. Further improvement of recovery and purity was obtained by the digestion of DNA present in the hybridoma supernatant using an endonuclease, benzonase. So far this strategy has been applied for the purification of up to 2 l hybridoma supernatants. 相似文献
53.
In the second part a practically important problem, namely the stability of relative equilibria of a dumbell satellite on an orbit around the Earth is treated by means of the reduced energy-momentum method. The dumbell satellite is used to emphasize the advantages of the reduced energy-momentum method which did not become obvious in the simple example of the rotating pendulum treated in Part I, as well as, to discuss some of the finer technical details. 相似文献
54.
Simulated moving bed (SMB) chromatography combines high productivity and high purities with reduced buffer consumption. We have developed a laboratory scale single column SMB (SC-SMB) unit with all four separation zones in one column. Distributors embedded within the chromatographic medium allow introduction and withdrawal of liquid between the zones. This single column unit exhibits homogenous packing in all zones, reduced headspace, less complex tubing, fewer valves, and almost undisturbed plug flow between the separation zones. The separation performance of the column was investigated with two different binary model mixtures. Furthermore, the SC-SMB unit is operated with a modified AKTA Explorer workstation, which has been specifically developed for the handling of biological fluids. 相似文献
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Alois Smolka 《Monatshefte für Chemie / Chemical Monthly》1887,8(1):64-68
Ohne Zusammenfassung 相似文献
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Ohne Zusammenfassung 相似文献
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Würger A 《J Phys Condens Matter》2011,23(50):505103
We study the viscoelastic properties of a film of n layers of spherical molecules confined between two walls. We find that the dynamic response arises from two competing contributions: the effective stiffness of n + 1 springs in series and softening due to strain fluctuations. In particular, the latter are the origin of the oscillatory behavior of the stiffness and the damping coefficient. The dissipation is strongest at the minima of the stiffness; the inverse behavior may occur for a modulated relaxation time. As a corollary we show that confined molecular layers cannot be described as Maxwell fluids. 相似文献
60.
Alois Steindl 《PAMM》2014,14(1):295-296
We investigate the stabilization of the radial equilibrium of a tethered satellite by tension control, if both in-plane and out-of-plane deviations from the vertical position are taken into account. While in-plane perturbations can be eliminated in finite time, the length rate change of the tether acts as parametric control on the out-of-plane deviations. Therefore the control becomes less effective, if the perturbation decreases. In order to improve the convergence we investigate the optimal control problem assuming no costs for the applied tension force but restricting the control force to a finite interval. For tether cconfigurations close to the vertical target position this approach yields a solution with singular control, which leads to a faster decay of the deviations. (© 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献