Two Plateau Moduli for Actin Gels

Conflicting experimental results have been reported for the plateau modulus in actin solutions: Analogies are often made with the viscoelastic behaviour of flexible polymers making use of the idea of entanglement as the source of the macroscopic storage modulus. We resolve apparent experimental and theoretical contradictions by pointing out the possibility of two distinct plateau regimes as a function of frequency in semidilute solutions of semiflexible polymers. We make the point that longitudinal and transverse hindrance can have very different effects at the macroscopic scale.