Highly sensitive and selective electrochemical determination of curcumin using a polyaniline-based molecularly imprinted polymer

Abstract

A novel and highly selective electrochemical sensor based on a polyaniline molecularly imprinted polymer modified glassy carbon electrode (MIP–PANI/GCE) was developed for the determination of curcumin. The molecularly imprinted polymer was synthesized directly on the electrode surface via electropolymerization of aniline in the presence of curcumin as a template molecule, followed by template extraction to generate specific recognition sites. Cyclic voltammetry was employed to investigate the electrochemical behavior and polymer formation, while differential pulse voltammetry was used for the sensitive and quantitative determination of curcumin. Key experimental parameters affecting the sensor performance, including solution pH, polymerization conditions, and curcumin concentration, were optimized. Under optimal conditions, the MIP–PANI/GCE electrode exhibited a significantly enhanced electrochemical response toward curcumin compared to the corresponding non-imprinted polymer (NIP) electrode, confirming the successful formation of selective binding cavities. The sensor demonstrated a wide linear dynamic range, low detection limit, good repeatability, and satisfactory regeneration capability. Moreover, high selectivity toward curcumin was achieved in the presence of potential interfering substances, highlighting the effectiveness of the molecular imprinting strategy. The proposed MIP-based electrochemical sensor combines simplicity of fabrication, low cost, and excellent analytical performance, making it a promising alternative to conventional analytical techniques for the sensitive and selective determination of curcumin in food, pharmaceutical, and related real samples.