Wide Linear Detection Range Glucose Biosensor Based on Composite Bioactive Films

This study presents an electrochemical glucose sensor featuring a nanoscale biointerface constructed from heat-denatured bovine serum albumin (dBSA)/Prussian blue (PB) complexes on indium tin oxide (ITO) electrodes. The sensing platform employs a novel modification strategy, where dBSA films activated by EDC/sulfo-NHS chemistry serve as a stable matrix for immobilizing glucose oxidase (GOx), enabling covalent conjugation of the enzyme. The enzymatic reaction between GOx and glucose induces electron transfer processes that modulate electrochemical currents, achieving signal transduction from biochemical reactions to electrical responses. The sensor demonstrates a linear detection range for glucose concentrations from 0 to 62.5 mmol <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathrm{L}^{-1}$</tex>, while the novel fabrication strategy offers valuable insights for developing other PB-based biosensors.