Innovative nanostructured aptasensor for the electrochemical detection of gluten in food samples

Gluten is a protein found in a wide variety of cereals, such as wheat, rye and barley. While important for the food fabrication process, the presence of gluten in these cereals can be dangerous for patients suffering from celiac disease or gluten allergy. Moreover, gluten can be found in trace amounts even in food products that should not theoretically contain it. For this reason, it is important to develop new, fast, and reliable methods for the detection of gluten in food samples. In this work, a nanostructured platform based on graphite and gold was developed, optimized and characterized. The platform was used for the construction of an aptasensor for the selective detection of gliadin, the component of gluten responsible for triggering celiac disease. The aptasensor was able to detect this analyte in a domain of 10-50000 ng/L with a limit of detection of 3.4 ng/L. The aptasensor proved to be sensitive and selective for the target analyte, even in wheat flour samples containing gluten, allowing the detection of gluten up to 10 & mu;g/kg of flour, but also in products from the category of gluten-free products such as gluten-free flour substitute comprised of a mixture of rice flour, carob flour, soy flour and starch and gluten-free breakfast cereals (muesli and breakfast cereals filled with hazelnut cream). Thus, the aptasensor proved useful for applications in food quality control, including for products from the gluten-free category, for which a maximum gluten content of 20 ppm (20 mg gluten/kg of product) is accepted.