Development and application of fluorescent immunoassay lateral flow Technology for the Detection of Prolamins in food

Lateral flow immunoassays (LFIAs) are well-suited for large-scale screening and on-site testing due to their simplicity and low cost. However, most current prolamin LFIAs primarily detect gliadins, exhibit limited broad-spectrum detection of hordeins and secalins, and lack validation in processed barley and rye foods, raising concerns about their practical reliability. To address these issues, thermally stable prolamin fractions were screened under simulated thermal processing conditions for antibody production. Using quantum dot carbodiimide random labelling, a sandwich LFIA was established with visual detection limits of 0.5, 1, and 0.5 μg/mL for gliadins, hordeins, and secalins, respectively. The LFIA detected flour contamination as low as 5 mg/kg in all three model food matrices. These findings demonstrate that the developed LFIA serves as a practical tool for rapid on-site detection of gluten prolamins in processed and commercial food products.