Principal Investigator Nikta Fakhri
Active force generation at the molecular scale in cells can result in stochastic non-equilibrium dynamics on mesoscopic scales. Molecular motors such as myosin can drive steady-state stress fluctuations in cytoskeletal networks. We develop a non-invasive technique to probe non-equilibrium fluctuations in an active gel using micron-long SWNTs. SWNTs behave essentially as semiflexible polymers. Both thermal and active motor-induced forces in the network induce transverse fluctuations of SWNTs. Active driven shape fluctuations of the SWNTs exhibit dynamics that reflects the non-equilibrium activity, in particular the emergence of correlations between the bending modes and observation of breaking of detailed balance in this configurational space of the SWNT probes.