Design of Biocompatible Liquid Cristal Elastomers Reproducing the Mechanical Properties of Human Cardiac Muscle

Advanced materials, able to work as integrated actuators for the treatment of muscle injuries, could combine rapid and long-lasting intervention, which is the main goal in regenerative medicine. Among them, Liquid Crystalline Elastomers (LCEs) are biocompatible polymers able to reversibly deform in response to a given stimulus by generating movement. Once stimulated, LCEs can mimic muscle force production. However, so far their application in biology was limited by the slow response times and the reduced possibility to modulate tension levels during activation. Thanks to a screening of different monomeric formulations, a palette of biocompatible LCEs is prepared and precisely characterized in isometric conditions in terms of passive and active mechanical properties, showing improved muscle-like characteristic. Light responsive LCEs stimulated with increasing laser powers, develop progressively increasing active tensions with fast kinetics of activation and relaxation. Tension levels and contraction time course can be modulate to reproduce twitch contractions of cardiac samples from patients affected by specific diseases. As a proof of concept, a LCE-based device able to develop concentric pressure, as in cardiac chambers, was demonstrated opening for their use in the preparation of contraction assist devices.