A Flexile Electrochemical Sensor via Interface-Engineered La ₂ O ₃ -Co Metallene Hybrids for High-Sensitive Dopamine Detection

Dopamine (DA), an important neurotransmitter, is closely related to neurological disorders, including Parkinson’s disease. Developing high-efficiency catalysts for ultrasensitive electrochemical sensors to detect trace DA still remains a key challenge. Herein, a La 2 O 3 -Co MAs hybrid was fabricated via the in situ growth of La 2 O 3 on Co metallene (Co MAs) by using a two-step strategy of microwave−ultrasonic and hydrothermal processes, showing a high sensitivity of 0.57 μA·μM −1 ·cm −2, a low limit of detection (LOD) of 6.9 nM and outstanding interference resistance for DA detection with high selectivity and long-term stability, which can be contributed to the built-in electric field at the heterointerface that can optimize the band structure and redistribute charge transition, significantly boosting catalytic oxidation behavior of DA. Further, this La 2 O 3 -Co MAs hybrid-derived flexible electrochemical sensor was prepared by low-cost screen-printing technology, exhibiting a wide linear range of 1−500 μM, a high sensitivity of 0.8 μA·μM −1 ·cm −2, and a low LOD of 4.97 nM for intracellular DA detection, with excellent flexibility, long-term stability, and biocompatibility. This work provides a strategy for improving the electrochemical sensing performance of the metallene-based hybrids via interface engineering and will expand its application in flexible electrochemical sensors for the detection of biomolecules.