Rapid on-site detection of shrimp allergen tropomyosin using a novel ultrafast PCR system

Shrimp is seafood that can commonly trigger allergic reactions. In this study, the ultrafast real-time PCR assay with portable device was developed to detect a shrimp-derived major allergen, tropomyosin, without complicated DNA extraction. For shrimp allergen detection, a specific primer pair was designed based on the shrimp tropomyosin gene and 18S ribosomal RNA gene as internal control. Primer specificity was assessed using 8 common seafood species. Serially diluted shrimp DNA was used to determine the limit of detection of the ultrafast PCR system, which was approximately 3.2 pg. Twenty-three food samples containing shrimp were evaluated to verify the applicability of a direct ultrafast PCR method for detecting shrimp allergens without DNA isolation. It took less than 30 min from sample preparation-to-result analysis to detect shrimp DNA in raw and processed samples. Therefore, this PCR system can be effectively and conveniently utilized in the field to detect shrimp in various food products.