Acetate-assisted in situ electrodeposited β-MnO2 for the fabrication of nano-architectonics for non-enzymatic glucose detection

Abstract

Highly sensitive and low-cost electrocatalytic materials are of great importance for the commercial application of non-enzymatic glucose sensors. Herein, we fabricated a novel one-pot enzyme- and indicator-free method for the colorimetric sensing of blood glucose levels based on the direct redox reaction of β-MnO₂/glucose. Owing to the introduction of ammonium acetate and the enhanced oxygen evolution reaction, the higher conductive β-MnO₂ nanosheets with the larger surface area were directly grown in situ on the conductive substrate by a linear sweep voltammetry (LSV) electrodeposition method. Besides, owing to the unique tunnel-type pyrolusite MnO₂, the electrolyte diffusion was facilitated and reduced the response time in the glucose detection process. Hence, the acetate-assisted MnO₂ electrode exhibited a high sensitivity of 461.87 μA M⁻¹ cm⁻² toward glucose, a wide detection range from 1.0 μM to 1 mM, and a low detection limit of 0.47 μM while the electrode also maintained excellent selectivity and stability. These results clearly indicate that the new strategy we developed has great potential for practical applications.