Bacterial Nanocellulose Functionalization for Smart Bioelectronics: Integration into Biosensing, Neural Interfaces, and Tissue Engineering

Bacterial nanocellulose (BNC), a renewable biopolymer biosynthesized by specific bacterial strains, exhibits exceptional mechanical strength, water retention, and biocompatibility due to its nanofibrillar 3D architecture and high purity. Functionalizing BNC with conductive polymers, metal nanoparticles, enzymes, and peptides unlocks its potential for diverse applications in smart bioelectronics, including biosensors, neural interfaces, and tissue engineering. This review presents a comprehensive analysis of recent strategies for tuning BNC's electrical, optical, biological, and mechanical properties to meet the evolving demands of next-generation biomedical and wearable devices. We discuss a broad range of functionalization methodsfrom in situ nanoparticle synthesis and electrostatic assembly to cross-linking and doping with ionic liquidsand explore their role in enhancing conductivity, stimuli-responsiveness, and cellular interactions. Furthermore, we examine BNC-based nanocomposites designed for biosensing, wound healing, optoelectronic sensing, and flexible implantable systems. The review concludes by outlining current key hurdles including scalability, device integration, long-term stability, and stringent regulatory requirements for safe production, use, and clinical translation, while uniquely positioning BNC through a cross-domain comparison of biomedical and electronic applications, complemented by techno-economic insights into scale-up, cost, and regulatory challenges.