Electrochemical Biofilms Enable Bioeffect-Informed Biofunctional Response Classification

Conventional concentration-based environmental assessment does not directly capture pollutant-induced biological responses, whereas existing bioassays often lack rapid, continuous, and biologically interpretable readouts. Here, we developed a bioeffect-informed response classification framework based on electrochemical biofilms (ECBs), which translates electrochemical signals into biofunctionally anchored classifications of biofilm impairment within approximately 7 min. ECB responses quantitatively tracked independently measured biofunctional perturbations and exhibited a strong dose–response relationship (R2 = 0.9987). A three-level classification was established using IC20 (0.830 μg L–1) and IC50 (3.939 μg L–1) response landmarks, whose biological significance was validated through structural, functional, and molecular analyses. Although the assays reflect different end points, ECB detected U(VI)-induced perturbations at concentrations over 3 orders of magnitude lower than the conventional Vibrio fischeri assay. Natural seawater validation demonstrated agreement with ICP–MS and enabled biofunctionally anchored classification, providing a rapid and interpretable strategy for effect-based water-quality screening.