RESUMEN
A method for quantitative detection of florfenicol by colloidal gold lateral flow immunoassay was developed.The experimental conditions including pH value, concentrations of antibody in the process of conjugation between the colloidal gold and antibody, amount of gold-labeled antibody, concentration of the antigen sprayed on test lines (T line), and detection time were optimized.With a colloidal gold strip reader, the signal intensity of T lines and control lines (C line) on lateral flow strips was recorded.The T/C ratio of negative control and positive samples was defined as B0 and Bx, and the standard curve was established by plotting the Bx/B0 ratio against the concentration of florfenicol.This assay showed a good linear range from 0.1 to 1.5 ng/mL with the limit of detection of 0.08 ng/mL, while the result could be obtained within 15 min.The result showed that this quantitative method was convenient and rapid, and could be used in screening a large amount of samples on site.