Biocompatible and stretchable chitosan piezoelectric gel with antibacterial capability and motion monitoring function for Achilles tendon rupture treatment.

Achilles tendon rupture is a common and serious condition that remains a challenge in the restoration of tendon structure and function. The design and use of high-performance piezoelectric materials serve as an effective solution to enhance repair outcomes, shorten recovery times, and reduce the risk of recurrence. In this study, we prepared a chitosan piezoelectric gel (CSPG) as an organic polymer with excellent biocompatibility, stretchability, and piezoelectric properties as well as excellent antibacterial properties. In vitro experiments showed that CSPG, which induces a piezoelectric effect, can inhibit bacterial growth, promote cell proliferation and migration, upregulate the expression of tendon-related genes, and inhibit the expression of inflammation-related genes. In vivo experiments showed improved outcomes for Achilles tendon repair following CSPG intervention, as evidenced by enhanced animal mobility and improved mechanical test results. In addition, the CSPG exhibited sensory functions capable of monitoring temperature and motion, providing timely feedback on repair efficacy. In summary, this study not only successfully prepared a multifunctional piezoelectric material that can effectively promote Achilles tendon rupture repair and regeneration and control inflammatory response, it also possesses antibacterial and sensing functions, thus offering a new strategy for Achilles tendon rupture repair.