A smartphone integrated finger-actuated microfluidic sensing platform based on dual-excitation N, Cl-doped carbon dots for detection of rifampicin

Dual-excitation N, Cl-CDs are synthesized for ratiometric RIF sensing. • Ratiometric detection of RIF is achieved with a detection limit of 58 nM. • The sensing mechanism involves synergistic IFE and FRET. • A smartphone integrated finger-actuated microfluidic device enables on-site visual RIF detection. • The platform exhibits satisfactory recovery in aquatic product samples. The increasing environmental prevalence of the antibiotic rifampicin (RIF) poses potential hazards to public health and ecological stability. Herein, a novel ratiometric assay is established by utilizing the dual-excitation nitrogen and chlorine co-doped carbon dots (N, Cl-CDs) for the quantification of trace amounts of RIF. Benefiting from the synergistic effects of the inner filter effect and Förster resonance energy transfer, the N, Cl-CDs act as a sensitive nanoprobe for RIF detection over a concentration range of 0.058–35 μM, with a detection limit of 58 nM. Furthermore, a novel finger-actuated microfluidic sensing platform has been developed through the integration of N, Cl-CDs. By combining the dual-excitation property of the probe with a smartphone-based RGB readout, the platform achieves on-site and visual quantification of RIF in real samples, as validated by high recovery rates ranging from 98.8% to 101.0%. Therefore, this work offers an innovative strategy for RIF sensing and establishes a versatile platform boasting prominent prospects for on-site food safety monitoring. Download: Download high-res image (150KB) Download: Download full-size image