Immuno-strip biosensor system to detect enrofloxacin residues

The immuno-strip biosensor was developed by combination of immuno-chromatography assay and sandwich enzyme linked immunosorbent assay (ELISA) techniques to detect enrofloxacin, a widely used broad-spectrum antibiotic. A proposed analytical system, consisted of immuno-reaction step and enzyme reaction step, has several advantages such as a very cheap manufacturing cost, a short analysis time (approximately 20 min), an easy-to-use, a high sensitivity, and a qualitatively confirmation by bare eyes. Enzyme reaction step in a proposed analytical tool could enhance the signal of immunosensor, resulting in the high sensitivity. A proposed system was successfully applied to detect enrofloxacin in a range of 100–10000 ppb. The lower detection limit was 100 ppb, which is the maximum residue limit of enrofloxacin in animal product.