Facile one-pot synthesis of Mn3O4 nanorods and their analytical application

Abstract

One-pot synthesis of Mn₃O₄ nanorods is reported for the first time by the oxidation of manganese metal resulting from reducing Mn²⁺ by NaBH₄ at room temperature. The resultant Mn₃O₄ nanorods were 10–70 nm in width and up to hundreds of nanometers in length, and were very stable in aqueous solution. The Mn₃O₄ nanorods can oxidize H₂O₂ under acidic conditions quickly accompanying their decomposition. Using 3,3′,5,5′-tetramethylbenzidine (TMB) as a competitive chromogenic substance, colorimetric methods were developed for the sensitive detection of H₂O₂ and glucose. The methods exhibited a linear range of 2–100 μM with a limit of detection (LOD) of 1.7 μM for detecting H₂O₂, and a linear range of 5–200 μM with a LOD of 4.4 μM for detecting glucose. The application in analyzing glucose in human serum samples demonstrates its practicability.