Odijk T
Section Theory of Complex Fluids, Faculty of Applied Sciences, Delft University, Leiden, The Netherlands.
Biophys J. 2000 Nov;79(5):2314-21. doi: 10.1016/S0006-3495(00)76477-0.
We consider the effect of polymer depletion on the transport (diffusion and electrophoresis) of small proteins through semi-dilute solutions of a flexible polymer. A self-consistent field theory may be set up in the important case of quasi-ideal interactions when the protein is small enough. Dynamic depletion, the reorganization of the depletion layer as the protein diffuses, is computed within a free-draining approximation. The transport of the dressed particle (protein + depletion layer) is tackled by extending Ogston's analysis of probe diffusion through fibrous networks to the case of a probe diffusing through a semi-dilute polymer inhomogeneous on the scale of the polymer correlation length. The resulting exponential retardation agrees almost quantitatively with that found in recent electrophoresis experiments of small proteins in polymer solutions that have been ascertained to be semi-dilute (S. P. Radko and A. Chrambach, Electrophoresis, 17:1094-1102, 1996; Biopolymers, 4:183-189, 1997).
我们研究了聚合物耗尽对小蛋白质在柔性聚合物半稀溶液中传输（扩散和电泳）的影响。当蛋白质足够小时，在准理想相互作用的重要情况下，可以建立自洽场理论。动态耗尽，即蛋白质扩散时耗尽层的重组，是在自由排水近似下计算的。通过将奥格斯顿对探针在纤维网络中扩散的分析扩展到探针在聚合物相关长度尺度上不均匀的半稀聚合物中扩散的情况，来处理被包裹粒子（蛋白质+耗尽层）的传输。由此产生的指数延迟几乎与最近在已确定为半稀的聚合物溶液中小蛋白质的电泳实验中发现的结果在数量上一致（S.P.拉德科和A.克兰巴赫，《电泳》，17:1094 - 1102，1996；《生物聚合物》，4:183 - 189，1997）。
