The Technology: I am developing a new kind of piezoresistive strain sensor capable of sustaining strains up to at least 25% and with a gauge factor far greater than that found in traditional resistive gauges. The sensor is designed as an elastomer-nanotube composite that deliberately avoids the major failure modes of traditional resistive strain gauges. In addition to improved elasticity and sensitivity, this type of sensor can be shaped into nearly any configuration and embedded in a variety of polymers. These attributes are particular important given that the application is to monitor forces in engineered muscle. The Application: I am designing my sensors to be integrated into engineered sheets of cardiac muscle. We have long been able to grow sheets of cardiac muscle, and the eventual goal is to implant these as 'patches' over damaged regions of the heart in order to improve function. However, despite extensive animal work having been performed, there are major difficulties, one of which is addressed by my sensor. Specifically, there are currently no reliable methods for testing the contractility of engineered muscle. The result is that there is absolutely no standardization in terms of the properties of the implants, nor is there any way of even evaluating different engineering approaches in terms of performance. By incorporating my sensors into a material commonly used as a support structure for engineered muscle, I am hoping to be able to monitor 'vital signs' (contractile force, in this case) during the development of the tissue.
Project end date: 08/16/11