Effect of Storage Time and Temperature on the Bioactivity of a Chitosan-Derived Epigenetic Modulation Scaffold

The appropriate storage protocol is one of the main limitations of translating tissue engineering technology to commercialized clinical applications. Recently, the development of a chitosan-derived composite scaffold incorporated with bioactive molecules has been reported as an excellent material to repair a critical size bony defect in mice calvaria. This study aims to determine the storage time and appropriate storage temperature of Chitosan/Biphasic Calcium Phosphate/Trichostatin A composite scaffold (CS/BCP/TSA scaffold) in vitro. The mechanical properties and in vitro bioactivity of trichostatin A (TSA) released from CS/BCP/TSA scaffolds in different storage times and temperatures were evaluated. Different storage times (0, 14, and 28 days) and temperatures (-18, 4, and 25 °C) did not affect the porosity, compressive strength, shape memory, and amount of TSA released. However, scaffolds stored at 25 °C and 4 °C were found to lose their bioactivity after 3- and 7-day storage periods, respectively. Thus, the CS/BCP/TSA scaffold should be stored in freezing conditions to preserve the long-term stability of TSA.