PETN reductase–coupled alcohol-selective enzymes for dual-mode PETN amperometric sensing and power generation

. The AOx-coupled designs expanded operational flexibility, while mechanistic studies revealed that HQ can promote the formation of insulating polymeric deposits during PETN conversion; vibrational and solid-state NMR analyses supported a heterogeneous aromatic-aliphatic network formation pathway. The developed biosensor was validated on post-explosion soil extracts against HPLC, yielding PETN levels around 1.6 μM with deviations ≤7% and RSD <7%. In addition, a one-compartment Zn/PETNR-ADH-HQ hybrid biofuel cell generated PETN-dependent electrical output (OCV up to 0.878 V at 50 μM PETN in model solutions) and operated directly in contaminated soil, supporting the feasibility of a proof-of-concept self-powered configuration complementary to the primary amperometric sensing mode. Overall, the proposed PETNR-centered cascade strategy provides a versatile proof-of-concept platform for PETN detection with potential for future adaptation toward portable electrochemical devices.