Development of a gold nanoparticles-based visual immuno-sensing platform for the rapid detection of gibberellins

As a common class of growth regulators, gibberellins (GAs) are widely used in agricultural production. However, the abuse and misuse of GAs have led to the problem of high residues in crops. The existing detection methods are still mainly instrumental, and rapid and sensitive detection of GAs remains a challenge. In this study, we designed a novel hapten scheme by analyzing the structure of GAs, which enabled the prepared mAb to simultaneously detect common GAs (GA3, GA1, GA4 and GA7) with high sensitivity and homogeneity. Subsequently, a colloidal gold immunochromatographic assay (GICA) for GAs detection was established by combining mAb with synthetic gold nanoparticles, which could simplify the sample pre-treatment step and the calculated limit of detection, visual limit of detection, cut-off values and linear ranges were 0.09 mg/kg, 0.2 mg/kg, 8 mg/kg, 0.13–1.36 mg/kg for rice and 0.11 mg/kg, 0.2 mg/kg, greater than 8 mg/kg, 0.13–2.45 mg/kg for tomatoes. The recovery assays of GA3-spiked samples ranged between 95.1% and 105.1%. The results indicate that our developed method can be used for the rapid, sensitive and efficient on-site detection of GAs in food.