Performance assessment of a new G12/A1 antibody-based rapid ELISA using commercially available and gluten-spiked food samples

Background Food products with < 20 mg/kg gluten can be labeled ‘gluten-free’ according to international regulations. Several antibodies based ELISAs have been develop to track gluten traces in food products. Among them, R5 and G12 antibody-based ELISAs are the frequently used methods. However, these antibodies have certain limitations. Aims We evaluated the accuracy of G12/A1 antibody-based 'Glutentox ELISA Rapid G12' and compared the results with the current reference method i.e., R5 antibody-based ‘Ridascreen R5 ELISA’. Methods In the first step, performance of Glutentox ELISA Rapid G12 kit was inspected by determination of the threshold value i.e.,> or < 20 mg/kg gluten in different food products. In the second step, quantification accuracy was assessed by quantification of gluten in gluten-free food products spiked with gliadin reference material. Results In total 47 food products (naturally and labeled gluten-free, and food with traces of gluten) were included. Of them, 29 products were quantified with < 20 mg/kg, and 18 with a low level of gluten by both the kits. Six out of 29 gluten-free products were used for the recovery test at different spike levels. Gluten concentration and mean recovery rates of individual kits showed consintency. Conclusions GlutenTox Rapid G12 ELISA could be an appropriate choice for detecting gluten in food products but needs more investigation e.g. more in-house validation and a collaborative test.