Macromolecular Doping of Polyaniline Toward All-in-One Supercapacitors with Enhanced Electrochemical Performance and Biocompatibility.

Limitations of conventional small molecule protonic acids used for doping polyaniline (PANI) including rapid performance degradation, potential cytotoxic effects, and the risk of provoking tissue inflammation; these pose significant challenges for biomedical applications. To overcome these issues, the use of poly(4-styrenesulfonic acid) (PSS) as a macromolecular dopant is proposed in this work; a stable PANI: PSS is synthesized and employed as an electrode material. This electrode material is integrated with a gel electrolyte formulated from gelatin and carboxylated chitosan to construct an all-in-one supercapacitor. This integrated design effectively eliminates interfacial resistance between the electrode and the electrolyte while simultaneously enhancing the mechanical integrity and operational stability of the device under physiological conditions. The all-in-one supercapacitor constructed by PANI: PSS as the electrode material demonstrates notable electrochemical performance, characterized by high specific capacitance, excellent long-term cycling stability, and reliable rate capability. Furthermore, comprehensive in vitro biocompatibility evaluations of the all-in-one supercapacitor are conducted, which reveal minimal cytotoxicity, no significant induction of inflammatory responses, and high blood compatibility, especially anticoagulant properties. These findings confirm the material suitability for use in implantable biomedical devices, and this study establishes a practical and reliable strategy for the development of safe, efficient, and biocompatible power sources.