A Y-Shaped Peptide-Based Antifouling Electrochemical Aptasensor for Sensitive Aflatoxin B1 Detection in Food

Conquering surface fouling of sensors caused by nonspecific adsorption and accumulation of foulants in a food matrix is of significance in accurate food safety analysis. Herein, an antifouling electrochemical aptasensor based on a Y-shaped peptide and nanoporous gold (NPG) for aflatoxin B1 detection in milk, tofu, and rice flour was proposed. The self-designed Y-shaped peptide involves an anchoring segment (-C), a support structure (-PPPP-), and an antifouling domain with two branches (-EK(KSRE)DER-) inspired by two bioactive peptides. NPG offers not only good electroconductibility but also anchor sites for peptides and aptamers. The antifouling surface can effectively resist fouling from single protein and carbohydrate solutions and even real food. The proposed aptasensor achieves sensitive detection with a low limit of detection of 0.26 pg mL^-1 (linear range: 0.001-10 ng mL^-1) and accurate analysis with minimal sample pretreatment (recoveries: 91.0-110.8%), offering a potential sensing platform to lower matrix interference.