Assembly of 3D‐ordered metal–organic aerogels for effective dopamine sensing

Abstract Complete collection of target fluids and effective capture of biomolecules are essential when designing and fabricating sensor electrodes. Assembling a conductive metal–organic framework (MOF) film onto a high‐surface‐area porous aerogel to create a three‐dimensional (3D) hierarchically ordered structure represented an effective strategy for fabricating sensor electrodes for body fluid detection. In this study, high‐precision, confined growth of a self‐assembled Cu‐HHTP layer on an aerogel assisted by atomic layer deposition was employed to fabricate a hierarchical 3D‐ordered metal–organic aerogel (MOA) electrode. This structure comprises two components: a conductive MOF thin film with abundant exposed active sites and a flexible 3D aerogel featuring through‐holes with strong adsorption capacity, thereby enhancing liquid confinement and promoting biomolecule adsorption. This approach combines the aerogel’s high flexibility and liquid adsorption ability with the conductive network of the Cu‐HHTP film, thereby enabling an effective dopamine (DA) sensor. The sensor based on the 3D‐ordered MOA electrode exhibits high sensitivity, with a detection limit of 1.19 μM, along with excellent selectivity, stability, reproducibility, and strong anti‐interference capability, as evidenced by negligible deviations in DA measurements across aqueous (H 2 O) and fetal bovine serum (FBS) samples. A proof‐of‐concept test using human urine produces a pronounced response, confirming the sensor’s practical feasibility.