Plasmonic genosensor for detecting hazelnut Cor a 14-encoding gene for food allergen monitoring

A plasmonic nanostructure was constructed as a biorecognition element coupled to an optical sensing platform in sandwich format, targeting the hazelnut Cor a 14 allergen-encoding gene. The analytical performance of the genosensor presented a linear dynamic range between 100 amol L^-1 and 1 nmol L^-1, a limit of detection (LOD) < 19.9 amol L^-1, and a sensitivity of 13.4 ± 0.6 m°. The genosensor was successfully hybridized with hazelnut PCR products, tested with model foods, and further validated by real-time PCR. It reached a LOD <0.001% (10 mg kg^-1) of hazelnut in wheat material (corresponding to 1.6 mg kg^-1 of protein) and a sensitivity of -17.2 ± 0.5 m° for a linear range of 0.001%-1%. Herein, a new genosensing approach is proposed as a highly sensitive and specific alternative tool with potential application in monitoring hazelnut as an allergenic food, protecting the health of sensitized/allergic individuals.