CONFORMATION TRANSITION AND COUNTERION DISTRIBUTION OF SINGLE POLYELECTROLYTE CHAINS

摘要

@@The mysteries of polyelectrolytes have been attracting research attentions for decades, and the complexity lying inside originates from multiple reasons, such as the long-ranged electrostatic interactions, existence of multiple charges, as well as the multiple molecular interactions. The dominant effect of electrostatic interaction controls the repulsion between the charges along the chain backbone, which in turn determines the chain conformation. Electrostatic interaction also attracts the counterions to the chain, which exerts an opposite effect to the entropy maximation. Therefore, the studies on chain conformation and counterion distribution have been two major research topics in polyelecrolyte physics. Here, we adopt single molecule fluorescence techniques to address the inter-play of these two factors with a model system of weak (or annealed) polyelectrolytes.