Carbon-Rich Monolayers on ITO as Highly Sensitive Platforms for Detecting Polycyclic Aromatic Hydrocarbons in Water: The Case of Pyrene

The determination of polycyclic aromatic hydrocarbons (PAHs) in water at low levels is a current challenge given their great impact on the health and safety of the public. Here, a novel pyrene-based self-assembled monolayer (SAM) platform is exploited as an electrochemical sensing recognition device. Interestingly, the formation of π–π sandwich complexes between PAHs and the recognition element switches the surface electron transfer capability. The unique supramolecular interaction between identical aromatic molecules provides a highly sensitive and selective sensor for pyrene in the order of part per trillion. Accordingly, and using pyrene as a proof-of-concept, this work presents the basis for an “at-point-of-use” impedimetric sensor focused on a highly sensitive carbon-rich SAM for PAHs determination in water at ultra-trace levels.