Nygren H
Department of Anatomy and Cell Biology, University of Göteborg, Sweden.
Biophys J. 1993 Oct;65(4):1508-12. doi: 10.1016/S0006-3495(93)81221-9.
The adsorption of ferritin at a methylized quartz surface was measured with off-null ellipsometry and transmission electron microscopy. An initial lag-phase was seen, followed by an accelerating adsorption leading to mass transport limitation of the reaction. The rate of adsorption then decreased at a surface concentration far below monolayer coverage, and a continuously decreasing rate of binding was seen. The slope of the binding rate was linear with the logarithm of time (fractal kinetics). The adsorbed ferritin molecules were distributed in clusters as seen by transmission electron microscopy. Clusters grown during the mass transport limited adsorption had crystalline structure at short range and low fractal dimensions (df = 0.89) over long range. Clusters grown during adsorption with fractal kinetics showed random structure at short range and a high fractal dimension df = 1.86 over all ranges. These findings indicate some new important mechanisms responsible for the complex kinetics of macromolecular reactions at solid-liquid interfaces. The results are discussed in relation to recently developed theories of self-organized criticality.
利用偏零椭偏仪和透射电子显微镜测量了铁蛋白在甲基化石英表面的吸附情况。观察到一个初始延迟期，随后是加速吸附，导致反应出现传质限制。然后，在表面浓度远低于单层覆盖时，吸附速率下降，并且观察到结合速率持续降低。结合速率的斜率与时间的对数呈线性关系（分形动力学）。如透射电子显微镜所见，吸附的铁蛋白分子呈簇状分布。在传质限制吸附过程中生长的簇在短程具有晶体结构，在长程具有低分形维数（df = 0.89）。在分形动力学吸附过程中生长的簇在短程显示出随机结构，在所有范围内都具有高分形维数df = 1.86。这些发现表明了一些新的重要机制，这些机制导致了固液界面大分子反应的复杂动力学。结合最近发展的自组织临界性理论对结果进行了讨论。
