The unique ability of piezoelectric materials to generate electricity spontaneously has attracted widespread interest in the medical field. In addition to the ability to convert mechanical stress into electrical energy, piezoelectric materials offer the advantages of high sensitivity, stability, accuracy and low power consumption. Because of these characteristics, they are widely applied in devices such as sensors, controllers and actuators. However, piezoelectric materials also show great potential for the medical manufacturing of artificial organs and for tissue regeneration and repair applications. For example, the use of piezoelectric materials in cochlear implants, cardiac pacemakers and other equipment may help to restore body function. Moreover, recent studies have shown that electrical signals play key roles in promoting tissue regeneration. In this context, the application of electrical signals generated by piezoelectric materials in processes such as bone healing, nerve regeneration and skin repair has become a prospective strategy. By mimicking the natural bioelectrical environment, piezoelectric materials can stimulate cell proliferation, differentiation and connection, thereby accelerating the process of self-repair in the body. However, many challenges remain to be overcome before these concepts can be applied in clinical practice, including material selection, biocompatibility and equipment design. On the basis of the principle of electrical signal regulation, this article reviews the definition, mechanism of action, classification, preparation and current biomedical applications of piezoelectric materials and discusses opportunities and challenges for their future clinical translation.
Vascular transplantation is an effective treatment for severe vascular lesions. The design of the bioactive and mechanical properties of small-caliber vascular grafts is critical for their application in tissue engineering. In this study, we sought to develope a small-caliber vascular graft by electrospinning a mixture of a human acellular amniotic membrane (HAAM) and polycaprolactone (PCL). Mechanical tests showed that the vascular grafts were strong enough to endure stress from adjacent blood vessels and blood pressure. The biocompatibility of the HAAM/PCL vascular grafts was evaluated based on cell proliferation in vitro. The tubular formation test demonstrated that vascular grafts containing HAAM could improve human umbilical vein endothelial cell function, and in vivo implantation was performed by replacing the rat abdominal aorta. The HAAM/PCL vascular graft was found to promote attachment and endothelial cell retention. The regenerated smooth muscle layer was similar to native arteries' smooth muscle layer and the endothelium coverage was complete. These results suggest that our constructs may be promising vascular graft candidates and can potentially be used to develop vascular grafts that can endothelialize rapidly in vivo.