Atomically dispersed palladium supported on graphene oxide for advanced electrochemical biosensing of dopamine

The rational design and construction of electrochemical sensing platforms with high sensitivity and selectivity remain a significant challenge. In this work, atomically dispersed palladium anchored on graphene oxide (ADC Pd/GO) was successfully fabricated through a simple wet impregnation method at room temperature, followed by inert ambient annealing. High-angle annular dark field scanning transmission electron microscopy (HAADFSTEM) confirmed the uniform distribution of single Pd atoms and sub-nanometric clusters of Pd across the surface graphene oxide. ADC Pd/GO demonstrated excellent catalytic performance in electrochemical dopamine sensing, achieving superior sensitivity and selectivity compared to both Pd nanoparticles-loaded graphene oxide and pure graphene oxide. Furthermore, the material maintained high performance in dopamine detection in the presence of interfering agents, uric acid and ascorbic acid. This work establishes a robust and versatile avenue for the rational design of atomically dispersed catalysts for electrochemical sensing with broad applications in biomedical research, healthcare, environmental monitoring, biotechnology, and food safety.