Needle−tip effect promoted flexible electrochemical sensor for detecting chloride ions in food by in−situ deposited silver dendrimers

Salt plays a crucial role in food processing and consumption, and the rapid detection of chloride ions in food and feed has great significance for practical applications. In this work, Ag−based nanomaterials were deposited on the surface of a flexible integrated electrochemical sensor for the detection of Cl⁻ in food. In order to enhance the detection performance, a unique needle−tip structure was formed by manipulating the electro−engraving process during the electrodeposition growth. Theoretical calculations and electrochemical investigations have demonstrated that the dendrimer’s rich tip structure significantly enhanced its electrochemical performance. A sensitive and flexible integrated electrochemical sensor was creatively developed for the detection of Cl⁻ using needle−tip effect−promoted Ag micro dendrimers. The sensor achieved quantitative detection of Cl⁻ over a dynamic range of 10.0 μM–100.0 mM, with a low limit of detection of 0.148 μM. The flexible electrochemical sensor proposed in this work exhibited good repeatability, selectivity and recoveries in real food samples.