Synthesis of imprinted chitosan/AuNPs/graphene-coated MWCNTs/Nafion film for detection of lead ions

Abstract

A promising electrochemical sensing platform based on imprinting chitosan (CS) nanocomposites integrating multi-walled carbon nanotubes (MWCNTs)/graphene (GR)/gold nanoparticles (AuNPs)/Nafion was developed for the sensitive and selective detection of Pb²⁺. The platform was constructed via drop coating and electrodeposition methods and characterized by using cyclic voltammetry, electrochemical impedance spectroscopy, and differential pulse voltammetry. Under the optimized conditions, the proposed sensor showed good sensitive determination of Pb²⁺ in the range of 1.0 × 10⁻⁹–5.0 × 10⁻⁵ mol L⁻¹ with a detection limit of 2.83 × 10⁻¹⁰ mol L⁻¹. In the presence of interfering metal ions, the fabricated sensor could selectively detect Pb²⁺. Meanwhile, the imprinted sensor exhibited high repeatability, good reproducibility and stability. The successful detection of Pb²⁺ in water and milk samples suggested its potential application for monitoring Pb²⁺ in complex water systems for environmental protection and food safety applications.