Reactive strip for quick and easy detection and quantification of allergens in food

A team from Universitat Politècnica de València (UPV), Universitat de València (UV) and Centro de Investigación Biomédica en Red sobre Enfermedades Raras (CIBERER) has developed a lateral flow test that reliably identifies and quantifies the level of allergens Eating with the help of a smartphone. The work was published in the journal biosensors.

“It is estimated that around 520 million people worldwide are affected by food allergies or sensitivities. These reactions mainly occur from eating foods that contain trace allergens. It is therefore important to identify and quantify them before eating the food, and that is what the test we have developed stands for,” says Sergi Morais, Professor in the Department of Chemistry at the Universitat Politècnica de València and researcher at the Inter -University Institute of Molecular Recognition and Technological Development (IDM).

The prototype was developed as a proof-of-concept for the simultaneous detection of almond and peanut allergens and has been validated with everyday commercial foods such as cookies and energy bars.

Among the benefits, the researchers highlight the reliability of the test, which includes multiple internal controls and calibrators integrated into a miniaturized 36-point array.

“With microarray technology, we perform 36 assays in a single step. Based on the information derived, we can determine whether the result is truly positive or negative. In addition, with the internal calibrators and the smartphone, we can quantify traces of allergen in the food with high precision,” says Ángel Maquieira, full professor at the Department of Chemistry at the Universitat Politècnica de València.

Regarding the extraction method, the UPV, UV and CIBERER team emphasizes simplicity, which means anyone can do it at any time.

“Current extraction methods consist of multiple steps and require sophisticated equipment to grind, degrease, extract and purify allergens. Therefore, the analysis is carried out in qualified laboratories. The aim is to decentralize the analysis, as happened with the COVID -19 test. We want everyone to be able to analyze a food just before eating it,” adds Sergi Morais.

The extraction method developed is based on the use of a portable mill, which grinds and filters the sample in a single step; 5ml of a solution is then added to extract the allergen and once the sample is prepared the test strip is immersed in the solution. And in just 5 minutes the result is obtained, which can be read with a mobile phone.

“At an estimated cost of €1 per strip, the developed test has great commercial potential, for example in the food sector for the rapid identification of allergens in situ and in the pharmaceutical sector for quantifying the effectiveness of allergen extracts used in allergy tests”, says Amadeo Sena , postdoc at the Interuniversity Institute for Molecular Recognition and Technological Development (IDM).

Future development

Looking ahead, the UPV, UV and CIBERER team point out that the test strip’s properties could easily be adapted for other allergens, as the group has specific antibodies for a wide range of allergens and biomarkers.

“Our challenge is to develop a test to simultaneously quantify the 14 allergens that must be declared according to Royal Decree 126/2015,” concludes Patricia Casino, researcher at the Instituto Universitario de Biotecnología i Biomedicina (BIOTECMED) – Universitat de València and the CIBERER.