Rapidly detecting major peanut allergen-Ara h2 in edible oils using a new immunomagnetic nanoparticle-based lateral flow assay

Ara h2 is a major peanut allergen that induces rashes, vomiting, diarrhea, and anaphylactic shock. Since peanut is a major source in producing edible oils globally, Ara h2 residues can be present in various edible oils. In this work, an immunomagnetic nanoparticle-based lateral flow assay for identifying Ara h2 in edible oils is developed. This assay exhibits high sensitivity with a visual detection limit of 0.1 mg/kg Ara h2 in oil, and favorable specificity in differentiating peanut from seeds and nuts. The calculated CV values of intra- and inter-assay were 6.73-10.21% and 4.75-8.57%, respectively, indicating high reproducibility. In an analysis of 26 oil products, Ara h2 was detected in two peanut oils as 0.122 ± 0.026 mg/kg and 0.247 ± 0.027 mg/kg. The entire method takes 5 h, including a 3.5-h sample preparation. Hence, this method has the potential to be an effective way to screen edible oils for Ara h2.