A scalable electrochromic sensor based on molecularly imprinted polymer for electrochemical and visual detection of Ritalin in human biofluids

چکیده مقاله

The medicolegal importance of the assay of ritalin (RIT), a misused central nervous system stimulant, has boosted demand for non-invasive and selective measurements. This study introduces a novel electrochromic sensor based on a molecularly imprinted polymer (MIP) strategy to electrochemically and visually measure RIT in human biofluids. This sensor integrates the advantages of a scalable indium tin oxide (ITO) electrode modified with polyaniline (PANI) and an MIP layer to selectively trap RIT on the embedded cavities on the sensing interface. The fabricated sensor is thoroughly characterized by various nanoscale investigation techniques and electrochemical and optical methods to confirm successful imprinting and favorable surface morphology. A wide linear dynamic range of 1 nM to 700 nM, with a low detection limit of 0.33 nM in this study, demonstrates the potential of the electrochromic platform for rapid and reliable detection of RIT. The proposed sensor exhibits excellent electrochemical stability, high selectivity, and reproducible responses with acceptable recovery and relative standard deviation values in fast salivary and urinary analyses of RIT. By using fewer materials and safe chemicals, low energy consumption, low waste generation, scalable miniaturized capabilities for easy, user-friendly assay RIT, the proposed sensing platform is validated against two international indices of green chemistry principles. The visual assay of the sensor, which is a bonus for rapid, on-site, and selective measurement of RIT, may promise real applications as a home-assay kit. Additionally, the proposed methodology may be applied to detect other targets by changing the corresponding MIP layer formation strategy. © 2026 The Authors.