Abstract
Wheat is a global staple, but its main protein, "gluten," can trigger severe reactions in people with celiac disease, an autoimmune disorder affecting around 1% of the population. The only treatment is a lifelong gluten-free diet. Gliadin, a gluten component, is the primary trigger and is difficult to detect due to its low solubility. This makes it challenging for celiac patients to safely eat out or to enjoy diverse foods. To address this, we developed LEO (Lateral flow Enhanced by Optical imaging), a portable gluten detection system combining lateral flow assays with smartphone-based image analysis. LEO uses IoT-enhanced technology to deliver results in under 3 min, accurately quantifying gliadin with over 98% accuracy and sensitivity below the FDA's 20 ppm threshold. In real-world trials, LEO successfully detected hidden gluten in mislabeled "gluten-free" restaurant dishes. With its fast, accurate results and user-friendly design, LEO supports safer food choices for individuals with celiac disease and is suitable for personal, clinical, industrial, and regulatory use.