Actin gels

Solutions and gels of the filamentous protein F-actin have not only been the subject of numerous recent biophysical studies, but have also proven to be quite fruitful model systems for fundamental polymer science. They are particularly good models of ‘semiflexible’ polymers, because they have an enormous ratio of persistence length to molecular diameter with characteristic mesh sizes of the order of one micron, which has permitted both a direct optical visualization of these networks and a number of recent experimental techniques for local viscoelastic characterization.