Thermo-regulated synthesis of NiMn layered double hydroxides for real-time determination of hydrogen peroxide in living cells and oxidase activity

Abstract

Hydrogen peroxide (H2O2) is an eminent reactive oxygen species, which induces serious cell damage in living system. Herein, we developed a thermo-regulated hydrothermal preparation of ultrathin two-dimensional (2D) nanopetals embedded NiMn LDH (NMH) microspheres for H2O2 detection. The effects of change temperatures on the surface morphologies and catalytic activities are investigated. The presence of 2D nanopetals on the surface of NMH microspheres offers abundant active sites towards H2O2 reduction and delivered excellent sensing parameters like lowest detection limit (2.5 nM (S/N = 3)) with a wide linear range (16 nM–9.3 mM), rapid response time (<3 s) and high sensitivity of 473.07 μA mM−1 cm−2. In addition, NMH based biosensor has been displayed excellent selectivity, stability, and reproducibility. Further, we extend the excellent analytical parameters of NMH based biosensor towards the real-time tracking and quantification of H2O2 production form various live cells and monitoring the oxidase activity. Interestingly, the developed biosensor delivered outstanding assay performance in all three real world situations with great consistency and reliability. All these results prove the excellent electrocatalytic performance of NMH microspheres, which enables developed assay as an effective point-of-care analytical device for clinical analysis.