Ru–W modified graphitic carbon nitride by a monomer complexation synthesis approach from a tailored polyoxometalate: towards electrochemical detection of hydrogen peroxide released by cells

Abstract

Detection of hydrogen peroxide (H₂O₂) from cell cultures is important for monitoring different diseases. Here, g-C₃N₄ (gCN) was incorporated into well-defined clusters of RuW (RuW–gCN) through monomer complexation of Ru-substituted phosphotungstate and melamine for electrochemical detection of H₂O₂. RuW–gCN exhibited enhanced electrochemical sensing properties in comparison to its constituents due to the synergic effects between RuW and gCN. The characterization of RuW–gCN revealed successful complexation to form the composite in addition to the presence of a layered structure of gCN. The electrochemical sensor made of RuW–gCN was able to detect H₂O₂ with a detection limit of 46 nM in the linear ranges from 100 nM to 50 μM and from 50 μM to 1 mM. The developed sensor was employed for the selective detection of H₂O₂ in the presence of analytes like ascorbic acid (AA), dopamine, and glucose in addition to being stable even after a week of storage at room temperature. It has also been verified for real sample application by detecting H₂O₂ produced by cancer cells as a result of an AA trigger.