In-situ synthesis of Ti-MOF@rGO composite for ultrasensitive and selective electrochemical sensing of dopamine

In-situ growth of Ti-MOF@rGO improves dispersion, reduces agglomeration, and facilitates electron transport. • 0.3–400 μM linear range, 0.114 μM LOD (S/N=3), selective vs UA/AA, stable/reproducible. • Synergistic Ti-MOF@rGO boosts DA adsorption and electron transfer via 2e - /2H + redox. Electrochemical detection of dopamine (DA) is critically important for the diagnosis and monitoring of neurological disorders. In this study, we present a novel composite material, Ti-MOF@rGO, synthesized in-situ through the integration of titanium-based metal-organic frameworks (Ti-MOFs) with reduced graphene oxide (rGO). This hybrid material effectively combines the abundant redox-active sites of Ti-MOF with the excellent electrical conductivity and large specific surface area of rGO, thereby facilitating efficient charge transfer and enhanced DA adsorption. The Ti-MOF@10%rGO-modified glassy carbon electrode demonstrated outstanding electrocatalytic performance for DA oxidation, exhibiting a wide linear detection range of 0.3–400 μM and a low detection limit of 0.114 μM (S/N = 3). The sensor exhibited high selectivity against common interferents such as uric acid and ascorbic acid, along with excellent repeatability, reproducibility, and cycling stability. This work presents a promising strategy for the rational design of MOF-based composites and offers a robust platform for ultrasensitive and selective electrochemical biosensing applications.