Immobilization of enzyme with MOF enhances colorimetric performance for fast, sensitive, and economical detection of chloramphenicol.

To ensure the safety of animal-derived foods, rapid and sensitive detection of chloramphenicol (CAP) residues is essential for monitoring antibiotic presence. To address this need, a modulated Metal-organic frameworks (MOFs) named NU-902 was synthesized, immobilizing horseradish peroxidase (HRP) onto its surface. Leveraging its colorimetric properties, the NU-902@HRP (NH) immuno-functionalized carrier was developed as a colorimetric probe. Polydopamine (PDA)-coated magnetic nanoparticles (MNPs) were employed as immunoreaction carriers, enabling rapid separation under an external magnetic field, significantly reducing antibody consumption by 80 % and lowering economic costs. This colorimetric biosensor achieves accurate CAP detection at concentrations as low as 0.0184 ng mL with an assay time of under 38 min. This biosensor can be used to detect CAP in various practical samples such as shrimp, eggs, milk, honey, beef, chicken liver and more. This biosensor represents a rapid, sensitive, and cost-effective approach for CAP determination.