Green Synthesis of ZIF-8 Combined with Ruthenium Nanoparticles for Enhanced Electrochemical Detection of Dopamine

A green synthesis approach was employed to develop ZIF-8, a Metal-Organic Framework (MOF) with high porosity and stability. To enhance its functionality for sensor applications, ZIF-8 was doped with ruthenium (Ru) nanoparticles, yielding Ru@ZIF-8. The structural and morphological characteristics of both ZIF-8 and Ru@ZIF-8 were systematically evaluated using X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET) surface area analysis, and infrared (IR) spectroscopy. Electrochemical studies revealed the excellent sensitivity and selectivity of Ru@ZIF-8 compared to pristine ZIF-8. Specifically, the sensitivity of the ZIF-8-based sensor was evaluated at 0.0035 μA·μM −1 , with a limit of detection (LOD) of 2 μM, whereas Ru@ZIF-8 exhibited significantly enhanced sensitivity of 0.141 μA·μM −1 and a detection limit of 0.05 μM. Both materials were further validated in real sample analyses using serum, demonstrating their applicability in complex biological matrices. The novelty of our work introduces a novel Ru@ZIF-8 sensor for dopamine detection, combining Ru nanoparticles and the ZIF-8 matrix to achieve superior performance. The sensor demonstrates exceptional sensitivity, a lower detection limit, a broader linear range and high selectivity against common biological interferences, surpassing conventional systems. This work underscores an environmentally friendly strategy for synthesizing advanced composites based on MOFs with enhanced detection capabilities for real-world applications.