A high-performance electrochemical sensor for the determination of Pb(II) based on conductive dopamine polymer doped polypyrrole hydrogel

Lead is one of the most common toxic heavy metals in the environment and it is easily accessible by the human body because there are residues in daily necessities and food. Therefore, it is significant to develop the high-performance detection method of lead ion (Pb(II)) in the environment and food. In this work, a sensitive and selective electrochemical sensing platform of Pb(II) was successfully constructed based on dopamine polymer doped polypyrrole (PDA-PPy) hydrogel modified screen-printed carbon electrode (SPCE) (noted as PDA-PPy/SPCE). PDA-PPy hydrogel was prepared by the hybridization of dopamine hydrochloride and pyrrole through a rapid and eco-friendly one-step synthesis method. Combined the selective adsorption capacity and good conductivity of PDA-PPy hydrogel, it was employed as the modified material for electrodes to achieve signal amplification. The result showed that PDA-PPy/SPCE exhibited excellent sensing performance towards Pb(II) with low detection limit of 0.15 μg L-1 and high sensitivity of 0.17 μg L-1 μA-1. Besides, acceptable recoveries were shown in real sample analysis, indicating that it has application prospects.