Researchers have investigated hydrogels as potential materials for biological monitoring. Hydrogel compositions have been designed to respond to changes in temperature, pH, glucose concentration and ionic strength concentration. Hydrogels designed to respond to changes in environmental conditions have demonstrated their ability to respond via a swelling or shrinking action. This swelling behavior can be exploited using a variety of signal transduction methods. While this technology shows promise, the degradation of hydrogel materials has not yet been characterized with respect to the shelf life of hydrogel samples or to their use in continuous testing. A series of experiments were performed to test hydrogels stored for extended periods of time then subjected to oscillatory testing, and the results have been analyzed to determine whether hydrogels can be used for extended periods of time for biological sensing applications.