Excess Charge in Polyampholytes

Abstract

Polyampholytes (PAs) are polymers composed of (quenched) random sequences of positive and negatively charged monomeric groups. We show that the radius of gyration, $R_g$, of a PA strongly depends on its overall excess charge $Q$, and is very weakly influenced by other aspects of the sequence. For $Q<Q_c\approx q_0\sqrt{N}$, where $N$ is the number of monomers of charge $\pm q_0$, the PA is compact, while for $Q>Q_c$ it is stretched. Some aspects of this behavior can be understood by analogy with the shape instability of a charged drop where the Rayleigh charge plays the role of $Q_c$.

11 pages, TeX, 3 uuencoded postscript figures

Cited by in corpus (24)

• Collapse of Flexible Polyelectrolytes in Multivalent Salt Solutions
• Instabilities of Charged Polyampholytes
• Collapse of Stiff Polyelectrolytes due to Counterion Fluctuations
• Structure of Polyelectrolytes in Poor Solvent
• Electrostatic complexation of spheres and chains under elastic stress
• A variational approach to necklaces formation in polyelectrolytes
• Dynamics of Collapse of flexible Polyelectrolytes and Polyampholytes
• Randomly Charged Polymers: An Exact Enumeration Study
• Hydrophobic Polyelectrolytes in Better Polar Solvent. Structure and Chain Conformation as seen by Saxs and Sans
• Like-Charge Colloid-Polyelectrolyte Complexation
• On the pearl size of hydrophobic polyelectrolytes
• Correlation length of hydrophobic polyelectrolyte solutions
• Collapse of Randomly Self-Interacting Polymers
• Conformational Instability of Rodlike Polyelectrolytes due to Counterion Fluctuations
• Freezing Transition of Compact Polyampholytes
• Phase transitions of a single polyelectrolyte in a poor solvent with explicit counterions
• Randomly Charged Polymers, Random Walks, and Their Extremal Properties
• Self-consistent variational theory for globules
• A Model Ground State of Polyampholytes
• Theta-point universality of polyampholytes with screened interactions
• Freezing in polyampholyte globules: Influence of the long-range nature of the interaction
• Statistics of Largest Loops in a Random Walk
• Ground States of Two-Dimensional Polyampholytes
• Dynamic charge density correlation function in weakly charged polyampholyte globules