In vitro and in vivo biocompatibility assessment of chalcogenide thermoelectrics as implants

The ability of thermoelectric materials to generate electricity in response to local temperature gradients makes them a potentially promising solution for the regulation of cellular functions and reconstruction of tissues. Biocompatibility of implants is a crucial attribute for the successful integration of thermoelectric techniques in biomedical applications. This work focuses on the in vitro and in vivo evaluation of biocompatibility for 12 typical chalcogenide thermoelectrics, which are composed of biocompatible elements. Ag₂Se, SnSe, Bi₂Se₃, Bi₂Te_2.88Se_0.12 and Bi₂Te₃, each with a released ion concentration lower than 10 ppm in extracts, exhibited favorable biocompatibility, including cell viability, adhesion, and hemocompatibility, as observed in initial in vitro assessments. Moreover, in vivo biocompatibility assessment, achieved by hematological and histopathological analyses in the rat subcutaneous model, further substantiated the biocompatibility of Ag₂Se, Bi₂Se₃, and Bi₂Te₃, with each possessing superior thermoelectric performance at room temperature. This work offers robust evidence to promote Ag₂Se, Bi₂Se₃, and Bi₂Te₃ as potential thermoelectric biomaterials, establishing a foundation for their future applications in biomedicine.