UiO-66-NH2-Deposited Gold Nanoparticles Enable Enhanced Interference-Resistant Immunochromatographic Assay for Rapid Detection of Gentamicin in Animal-Derived Foods

Gentamicin (GEN) is a broad-spectrum antibiotic widely used in livestock production, and its excessive residues in animal-derived foods pose potential health risks to consumers. However, conventional colloidal gold immunochromatographic assays (AuNPs-ICA) often suffer from low sensitivity and poor tolerance to sample matrices. Herein, a UiO-66-NH₂ framework decorated with gold nanoparticle (UiO-66-NH₂@Au)-based ICA was employed to construct an ICA platform for GEN detection, combining the optical advantages of AuNPs with the protective and stable octahedral framework of the Metal-organic framework (MOF) to enhance antibody stability under extreme conditions. The method achieved limits of detection for GEN of 0.1 µg/kg in four tested matrices, with recoveries of 80.1-112.0% and coefficients of variation below 11.7%. Compared to traditional AuNPs-ICA, the sensitivity was improved by up to 30-fold, the pH tolerance range was expanded from 6-8 to 4-10, and the organic solvent tolerance to organic solvents expanded up to 40%. Verification with 40 real samples demonstrated excellent correlation (R² > 0.99) with results from commercial ELISA kits. This UiO-66-NH₂@Au-ICA platform offers a new technical solution with high sensitivity, strong good anti-interference performance, and robustness for rapid field detection of GEN residues in products of animal origin and holds significant practical importance for advancing rapid food safety detection technologies.