Encapsulation of enzyme by metal-organic framework for single-enzymatic biofuel cell-based self-powered biosensor

Self-powered biosensor, as a new sensing platform, utilizes biofuel cells as synchronous power source and biosensor system, with the advantages of no external power source , simple instrumentation and easy miniaturization. Meanwhile, inspired by biomimics for the encapsulation of soft tissue within protective exteriors in nature, encapsulation of biological macromolecules by metal organic-frameworks (MOFs) have been proved to be an effective strategy for enhancing the biocatalytic activity in maintaining biological functions. Herein, we successfully encapsulated laccase (LAC) in zeolitic imidazolate framework-8 (ZIF-8) and combined it with bacterial cellulose (BC)/carboxylated multi-walled carbon nanotubes (c-MWCNTs) skeleton to prepare highly flexible BC/c-MWCNTs/ZIF-8@LAC electrode. Subsequently, we ingeniously designed an highly flexible self-powered sensing platform based on biofuel-cell driven by single-enzyme, harvesting bisphenol A (BPA) as a model analyte. The maximum power density (P max ) of single-enzymatic biofuel cell (EBFC) exhibited an excellent linear dynamic range from 0.01 to 0.4 mM with a lower detection limit of 1.95 × 10 −3  mM for BPA concentrations. Therefore, the designed single-EBFC-based self-powered sensor is feasible in BPA detection and has a broad application prospect in the field of water pollutants detection.