聚電解質之形狀對其電泳及沉降行為之影響

Abstract

膠體科學在現代科學領域中有相當廣泛的應用，近年來普遍被使用於生物感測、藥物傳輸、與DNA定序等方面。聚電解質為離子與液體可穿透之巨型帶電分子，常被採用於模擬生物粒子的行為，本文特別針對其電泳以及沉降行為進行理論分析。為了使模擬更貼近真實情況，吾人同時考慮了聚電解質的形狀因子、電雙層極化/鬆弛極化效應、電滲透阻流、和反離子凝聚效應。經由分析電力和流力的交互作用，佐以平均局部電場強度和平均淨離子電荷密度，吾人得以在不使用波茲曼分布假設的情況下，定性和定量地合理解釋相關的機制。本論文結果不僅對聚電解質電泳及沉降作用現象進行討論，也提供了實驗研究學者在設計及參數設定時具參考價值的資訊。

Colloidal particles are widely adopted in modern scientific applications, such as biosensing, drug delivering, and DNA sequencing, to name a few. Polyelectrolytes (PEs), ion and liquid penetrable charged macromolecules are often adopted to simulate biomolecules. Its electrophoresis and sedimentation behaviors are analyzed in this study. To be more realistic, the effects of PE shape, double-layer polarization, double-layer relaxation, electroosmosis and counterion condensation are taken into account, and therefore, it is by far the most thorough study. Through considering the interaction of the electric force and the hydrodynamic force acting on a PE, the local induced electric field, and the effective PE charge density, we examined the PE behavior without assuming Boltzmann distribution for mobile ions. In addition to establish theoretical background for describing the behaviors of a PE, the results gathered in this study also provide necessary information for experimental design.