Augé Sophie, Schmit Pierre-Olivier, Crutchfield Christopher A, Islam Mohammad T, Harris Douglas J, Durand Emmanuelle, Clemancey Martin, Quoineaud Anne-Agathe, Lancelin Jean-Marc, Prigent Yann, Taulelle Francis, Delsuc Marc-André
Centre de Biochimie Structurale, CNRS UMR 5048 - UM 1 - INSERM UMR 554, 29, rue de Navacelles, 34090 Montpellier Cedex, France.
J Phys Chem B. 2009 Feb 19;113(7):1914-8. doi: 10.1021/jp8094424.
Experimental NMR diffusion measure on polymers and on globular proteins are presented. These results, complemented with results found in the literature, enable a general description of effective fractal dimension for objects such as small organic molecules, sugars, polymers, DNA, and proteins. Results are compared to computational simulations as well as to theoretical values. A global picture of the diffusion phenomenon emerges from this description. A power law relating molecular mass with diffusion coefficients is described and found to be valid over 4 orders of magnitude. From this law, the fractal dimension of the molecular family can be measured, with experimental values ranging from 1.41 to 2.56 in full agreement with theoretical approaches. Finally, a method for evaluating the molecular mass of unknown solutes is described and implemented as a Web page.
本文展示了对聚合物和球状蛋白质进行的实验性核磁共振扩散测量。这些结果，再结合文献中的结果，能够对诸如小有机分子、糖类、聚合物、DNA和蛋白质等物体的有效分形维数进行一般性描述。将结果与计算模拟以及理论值进行了比较。从这一描述中浮现出扩散现象的整体图景。描述了一个将分子量与扩散系数相关联的幂律，并发现其在4个数量级范围内有效。根据该定律，可以测量分子家族的分形维数，实验值在1.41至2.56之间，与理论方法完全一致。最后，描述了一种评估未知溶质分子量的方法，并将其实现为一个网页。
