An effective and simple strategy for highly selective and anti-interference detection of dopamine based on the carbon quantum dots-molecularly imprinted polymers modified electrode

Dopamine (DA) dysfunction is known to cause neurological and physiological disorders, such as schizophrenia, Parkinson's disease, and addictive behavior. Therefore, dopamine detection is essential for both diagnosis and disease prevention. In this study, a novel and effective electrochemical sensor was fabricated based on a carbon quantum dots (CQDs)@molecularly imprinted polymers (MIPs) modified electrode for dopamine detection. The CQDs were obtained by an eco-friendly hydrothermal carbonization method, using sycamore leaves as a natural carbon source. The structure of the prepared CQDs@MIPs composite was confirmed through techniques including Ultraviolet–visible absorption spectroscopy, dynamic light scattering technique, scanning electron microscopy, and transmission electron microscopy. By combining the rapid electron transfer rate of the CQDs with the selective activity of the MIPs, the prepared CQDs@MIPs composite-modified electrode demonstrated greatly enhanced electrochemical performance. The developed sensor exhibited a good response towards dopamine detection, with a considerably lower detection limit (5 × 10⁻⁹ M) and a wider linear range (5 × 10⁻⁹–5 × 10⁻⁴ M) compared to current publications. In addition to the outstanding reproducibility and anti-interference ability, this ‘green sourced’ sensor showed great potential for practical applications, as validated by the satisfactory recovery analysis of dopamine from goat blood serum.