Two-dimensional layered nanomaterials for electrochemical dopamine sensing: Recent advances, challenges, and future perspectives

Dopamine (DA) is a vital neurotransmitter involved in numerous physiological functions, and its abnormal levels are directly linked to severe neurological disorders such as Parkinson's disease, schizophrenia, and depression. The accurate and sensitive detection of dopamine in biological fluids remains a major challenge due to its low concentration and interference from structurally similar biomolecules such as ascorbic acid and uric acid. In recent years, two-dimensional (2D) layered nanomaterials have emerged as powerful candidates for enhancing the performance of electrochemical dopamine sensors. Their unique properties including high surface area, tunable bandgap, excellent electrocatalytic activity, and easy functionalization enable improved sensitivity, selectivity, and miniaturization of sensing platforms. This review presents a comprehensive overview of recent advances in the development of 2D nanomaterials such as graphene, MoS₂, WS₂, MXenes, and black phosphorus for electrochemical dopamine sensing. Key parameters such as detection limits, response times, and sensor stability are systematically analyzed. The review also discusses the mechanisms of dopamine oxidation, surface modification strategies, and integration with flexible or wearable systems. Current challenges, including biocompatibility, reproducibility, and multiplexed detection, are critically evaluated. Finally, we highlight future directions for clinical applications and intelligent biosensing platforms using 2D nanomaterials. This work aims to provide researchers with a solid foundation and strategic insights for advancing dopamine sensing technologies based on emerging 2D materials.