Enhanced electrochemical sensing platform based on porous Co3O4 nanocubes/3D MX-rGO aerogel for sensitive detection of dopamine

Accurate and sensitive detection of the neurotransmitter dopamine (DA) plays a significant role in medical diagnosis and human health assessment. Herein, an electrochemical sensing platform for ultrasensitive determination of DA was constructed based on porous Co 3 O 4 nanocubes anchored to three-dimensional Ti 3 C 2 MXene-reduced graphene oxide aerogel (Co 3 O 4 /3D MX-rGO). The 3D MX-rGO aerogel with a high specific surface prevents aggregation of Co 3 O 4 nanocubes and exposes more active sites, resulting in excellent electrocatalytic activity and outstanding sensing properties. The electrochemical reaction kinetic was investigated in detail, a possible sensing mechanism was proposed, and the interaction mechanism between the composites and DA was revealed combined with density functional theory (DFT) calculations. Under optimized experimental conditions, the sensor developed using Co 3 O 4 /3D MX-rGO modified glassy carbon electrodes (GCE) exhibited low detection limits (40 nM) in the range of 0.1–300 μM for DA with good selectivity, reproducibility, and stability. The sensor has been successfully use to detect DA in human serum and urine samples with recoveries of 95.3 %-103.7 %, which has great potential for practical applications.