New Cation Sensors Based on Eugenol-Derived Azo Dyes.

Eugenol-based azo dyes illustrate how bio-sourced compounds like eugenol can be transformed through synthetic processes into functional and colorful compounds. The main purpose of the present work was to develop new responsive colorimetric sensors for metal cations based on eugenol-derived azo compounds. The incorporation of the azo group into the eugenol framework allows for strong electronic interactions with metal cations, leading to distinct color changes observable to the naked eye. These azo-eugenol dyes exhibit shifts in their UV-Vis absorption spectra upon complexation with metal cations such as copper (Cu2+) and lead (Pb2+), making them effective sensors for environmental and analytical applications. The eugenol-based azo dyes were subjected to photophysical studies to understand selectivity, response time, and stability in relation to metal cations, which will be a starting point for the monitoring of toxic metal contaminants in aqueous environments.