An Electrochemical Sensor Based on Chalcogenide Molybdenum Disulfide-Gold-Silver Nanocomposite for Detection of Hydrogen Peroxide Released by Cancer Cells.

Hydrogen peroxide (H2O2) as a crucial signal molecule plays a vital part in the growth and development of various cells under normal physiological conditions. The development of H2O2 sensors has received great research interest because of the importance of H2O2 in biological systems and its practical applications in other fields. In this study, a H2O2 electrochemical sensor was constructed based on chalcogenide molybdenum disulfide-gold-silver nanocomposite (MoS2-Au-Ag). Transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and energy dispersive spectroscopy (EDS) were utilized to characterize the nanocomposites, and the electrochemical performances of the obtained sensor were assessed by two electrochemical detection methods: cyclic voltammetry and chronoamperometry. The results showed that the MoS2-Au-Ag-modified glassy carbon electrode (GCE) has higher sensitivity (405.24 µA mM-1 cm-2), wider linear detection range (0.05-20 mM) and satisfactory repeatability and stability. Moreover, the prepared sensor was able to detect the H2O2 discharge from living tumor cells. Therefore, this study offers a platform for the early diagnosis of cancer and other applications in the fields of biology and biomedicine.