淺介軟物質中不尋常的靜電作用

Introduction to the unusual electrostatic effects in soft matter

陸駿逸(C.-Y. David Lu)

《化學》 62卷3期 (2004/09) Pp. 371-376

https://doi.org/10.6623/chem.2004030

摘要

本文簡單介紹近年來軟物質研究中幾個不尋常的靜電現象。膠體懸浮液中的巨離子在恰當的條件下顯現出吸引力並能聚集成高密度凝聚相。目前的研究逐漸認定這個吸引力源自於多體效應。類似的同電性相吸引的現象也在DNA溶液中被觀察到。在低鹽濃度下，多價陽離子能引起DNA間的吸引力並形成DNA bundle。DNA彼此間的吸引力來自於凝聚在DNA附近眾多的陽離子的熱涨落與其關聯分佈。最後並介紹DNA與histone蛋白複合結構的電荷反演現象，與DNA及人工合成的正電脂質形成的自組裝結構。

關鍵字

卜松波茲曼理論 ； 去氧核糖核酸 ； 正電脂質 ； 電荷反演

並列摘要

We introduce a few electrostatic effects which attract the researchers in soft matter during the last ten years. Under the suitable condition, charged colloid particles of the same charge seem to attract each other to form condensed phases. The attraction is now identified as the many body interaction. The like charge attraction also arises in the DNA bundle which forms under the low ionic strength and the presence of the multivalent cations. The DNA charge condensation plays an important role here, where the fluctuation and the correlation of the condensed cations are responsible for the attraction between DNA. We also discuss the charge reversal of the DNA-histone complex, which is the fundamental building block of the chromosome. Finally the structure and the formation kinetics of the DNA-cationic lipid complex is briefly mentioned.

並列關鍵字

Poisson-Boltzmann theory ； DNA ； histone ； nucleosome ； cationic lipid ； charge reversal