Establishment of fumonisin B₁ detection method for catalytic fluorescence detection of aptamer-regulated carbon dots

Mycotoxin, common in agricultural products, is a small secondary metabolite with strong toxicity. Fumonisin B₁ (FB₁) is the most common and the most toxic. Establishing a rapid detection method is important for preventing and controlling FB₁ pollution. This study prepared carbon dots (CDs) from 2,2'-dithiosalicylic acid (DTSA). Tetramethylbenzidine (TMB) can be catalyzed to produce fluorescence by CDs, while FB₁ can adhere to the surface of CDs, decreasing fluorescence. Aptamer F10 of FB₁ combines with FB₁ attached to the surface of CDs to restore the catalytic ability of CDs and increase the fluorescence value. This method has good linearity in the FB₁ concentration range from 0 to 1.0 μg mL^-1. The standard curve was Y = -0.2512x + 661.4, R² = 0.9903, the limit of detection (LOD) was 17.67 ng mL^-1 and limit of quantitation (LOQ) was 53.55 ng mL^-1. The recovery of the corn sample was 89.83-98.62%, and the detection time was 30 min.