Tunable Bio‐Derived Bimetallic Cu–Zn/2‐AA Metal–Organic Framework as an Efficient Electrode Modifier for Detection of Cadmium and Dopamine

To develop multifunctional sensors capable of detecting both cadmium toxicity and dopamine dysregulation, it is essential to use specialized materials that are highly selective and sensitive to these distinct chemical targets. Metal–organic frameworks (MOFs) are well known for their high porosity, large surface area, and tunable structures, which facilitate efficient enrichment and mass transfer of analytes. This, in turn, enhances signal response and improves sensor sensitivity. In this study, we synthesized a bio‐derived bimetallic MOF, referred to as Cu–Zn/2‐AA, and effectively employed it as a modification material for electrochemical sensing applications. To confirm the successful formation of Cu–Zn/2‐AA, we utilized several techniques, including Fourier transform infrared spectroscopy, X‐ray diffraction, scanning electron microscopy coupled with energy‐dispersive X‐ray spectroscopy, and thermogravimetric analysis. The electrochemical sensing results revealed that the Cu–Zn/2‐AA‐modified screen‐printed electrode (SPE) demonstrated an over 2400% improvement in performance compared to the bare SPE for detecting cadmium and dopamine. We achieved a wide linear detection range from 0.7 to 800 femtomolar (fM) for cadmium and 25–600 attomolar (aM) for dopamine. Furthermore, the detection limits were calculated to be 0.11 fM for cadmium and 7 aM for dopamine, showcasing the sensor’s exceptional sensitivity. This MOF also exhibited high selectivity in the presence of interfering species. Overall, Cu–Zn/2‐AA holds great promise for the development of a new class of electrochemical sensing platforms for ultrasensitive and reliable detection.