The rapid and accurate detection of peanuts and soybeans allergen is important to the food safety. In this study, Cu-TCPP nanosheet, a kind of ultra-thin metal-organic framework (MOF) was synthesized and applied in loop-mediated isothermal amplification (named Cu-TCPP@LAMP), which can inhibit the non-specific amplification by absorbing and precise temperature releasing of single primer. As thus, Cu-TCPP@LAMP can achieve high sensitivity and specific amplification of the target gene. As a result, peanut and soybean allergens genes contained in food were successfully detected with a favorable detection sensitivity (5 ng/μL for peanuts and 10 ng/μL for soybeans) and reliable repeatability (The coefficient of variation was 3.38% for peanuts and 3.33% for soybeans). Moreover, the established method was utilized for detection of several commercial products, and had a high consistency with the standard method. Apart from food allergens, this novel assay can be widely used in other areas, such as pathogen detection, tumor nucleic acid detection and so on.

Little information was so far available about allergenic mechanism of the roasted peanut allergens during initial stages of allergy. The purpose of this study was to determine the influence of roasting (150 °C, 20 min) on biochemical and biological properties of Ara h 3, a major peanut allergen. Allergenicity of roasted peanut emulsion to mice, differences in uptakes between Ara h 3 purified from raw peanuts (named as Ara h 3-Raw) and that purified from roasted peanuts (named as Ara h 3-Roasted) by bone marrow-derived dendritic cells (BMDCs) and the implication of cell surface receptors involving in uptake, and changes in glycosylation and structure of Ara h 3 after roasting were analyzed in this study. This study suggested that roasting increased allergenicity of peanut to BALB/c mice. Maillard reaction and structural changes of Ara h 3 induced by roasting significantly altered the uptake of Ara h 3-Roasted by BMDCs, and modified Ara h 3 fate in processes involved in immunogenicity and hyper allergenicity, indicating that food processing pattern can change food allergenicity.