Enhanced Nonenzymatic Sensing of Hydrogen Peroxide Released from Living Cells Based on Graphene Aerogel/Platinum Nanoparticle

The high levels of H2O2 are closely associated with cancer and progressive neurodegenerative diseases. Therefore, the accurate and sensitive detection of hydrogen peroxide is of great importance. In this study, we report a facile hydrothermal fabrication of graphene aerogel/platinum nanoparticle (GA/Pt NPs) nanocomposites with three-dimensional (3D) interconnected pores. The GA/Pt NPs product were first characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). Cyclic voltammetry (CV) measurements reveal that GA/Pt NPs can directly catalyze the reduction of H2O2 and display enhanced current responses. The biosensor exhibits remarkable sensitivity (138.23 mu A mM(-1) cm(-2)), an approximate linear detection range of H2O2 concentration (1 mu mol . L-1 to 2785 mu mol . L-1), and a detection limit of 0.33 mu mol . L-1. Moreover, good anti-interference property, reproducibility, and long-term stability of the enzymeless sensor were achieved. These results indicate that GA/Pt NPs is a good candidate for H2O2 detection. Due to these remarkable analytical advantages, the as-made sensor was applied to determine the H2O2 released from PC12 cells with satisfactory results. These results demonstrate that this new nanocomposite with the high surface area and electrocatalytic activity is a promising candidate for use as an enhanced electrochemical sensing platform in the design of nonenzymatic biosensors.