Development of a multicomponent immunochromatographic test system for the detection of fluoroquinolone and amphenicol antibiotics in dairy products.

Ciprofloxacin (CIP) and chloramphenicol (CAP) are relevant antibiotics of the fluoroquinolone (FQ) and amphenicol (AP) groups, respectively, widely used in veterinary practice and they contaminate agricultural products. In this study, a rapid and sensitive immunochromatographic assay (ICA) was developed for simultaneous detection of CIP and CAP in dairy products. The ICA was carried out in a direct competitive format using gold nanoparticles as a label. The ICA developed here allowed for the detection of CIP and CAP in Triton X-100-containing buffered saline (PBST) within 15 min with instrumental detection limits of 20 pg mL-1 and 0.5 ng mL-1 , respectively, and with a visual detection limit of 5 ng mL-1 for both antibiotics. The ICA showed cross-reactivity (69-160%) to 19 antibiotics in the FQ group and no cross-reactivity (<0.1%) to 2 antibiotics of the AP group. The ICA allowed detection of CIP and CAP in a panel of dairy products by employing a simple procedure of preliminary sample preparation. The detection limits for the two antibiotics were the same as in PBST. The analytical recoveries of CIP and CAP in dairy products ranged from 83% to 120%. The analytical characteristics of the test system allow its use for the detection of antibiotics in milk and dairy products during all steps of production. © 2019 Society of Chemical Industry.