An integrated electrochemiluminescence microfluidic device for detecting ultra-low concentration of ceftriaxone

Ceftriaxone sodium, a widely used third-generation cephalosporin antibiotic, poses significant health risks when residues accumulate in clinical or environmental settings. However, conventional detection techniques, including high-performance liquid chromatography and capillary electrophoresis, are limited by complex procedures, poor sensitivity, and a lack of real-time capability. To address these challenges, we report a sensitivity-enhanced electrochemiluminescence (ECL) microfluidic device for the rapid and label-free detection of ultra-low concentrations of ceftriaxone. Au₂₅(Capt)₁₈ gold nanoclusters were served as a novel ECL luminophore to boost detection sensitivity, while a 3D-printed circulating microfluidic channel was designed to enrich ceftriaxone via inertial centrifugation. The device achieved a wide detection range of 4–400 μg/mL, a low detection limit of 0.522 μg/mL, and an average recovery of 99.1 % in real sample tests. This integrated platform offers a promising strategy for simple, sensitive, and on-site monitoring of ceftriaxone contamination.