High bandwidth optical force clamp for investigation of molecular motor motion

Use of optical tweezers for load force regulation on processive motors has yielded significant insights into intracellular transport mechanisms. The methodology developed in this letter circumvents the limitations of existing active force clamps with the use of experimentally determined models for various components of the optical tweezing system, thus making it possible to probe motor proteins at higher speeds. This paradigm also allows for real-time step estimation for step sizes as small as 8 nm with dwell time of 5 ms or higher without sacrificing force regulation.