Applications of Triboelectric Nanogenerators in Bone Tissue Engineering

Bioelectricity has been a fundamental property of all living organisms. With electrical stimulation, living cells can interact with their microenvironments, which makes electrical stimulation highly beneficial for various biomedical applications. However, traditional electrical stimulation mainly relies on bulky and complex equipment, which may not be ideal due to the restriction of movement, limited battery lifetime, uncomfortable wearing, and potential unfriendly to the environment. The advent of triboelectric nanogenerators (TENGs) has helped to resolve the existing limitations. TENGs are effective energy harvesting systems that use a mix of triboelectrification and electrostatic induction to create electrical energy from kinetic energy. TENGs deliver self-powered electrical stimulation to bone cells for functional regulation or bone regeneration, serve as sensors to detect biological signals or movements, or act as a power source for other biomedical devices. TENGs can be employed in various applications, including enhancing bone regeneration, providing sensing function, slowing bone aging, and curing implant-related infections. The recent applications of TENGs in bone tissue engineering are reviewed, and the drawbacks of the TENGs are discussed. Finally, the existing challenges and future roadmap for developing TENGs are presented.