Determination of cow's milk β-lactoglobulin allergens in foods based on a rapid and sensitive immunochromatographic test strip method

The presence of β-lactoglobulin (β-Lg), one of the major food allergens, poses a significant health risk to allergic populations. Therefore, the development of a method for the rapid detection of β-Lg is particularly urgent, aiming at the effective prevention of adverse reactions in allergic patients after exposure to or ingestion of foods containing this allergen. In this study, a lateral flow colloidal gold immunoassay strip test was constructed using colloidal gold-labeled mouse anti-β-Lg monoclonal antibody (mAb1) and goat anti-mouse polyclonal antibody by double antibody sandwich immunochromatography. After optimizing the signal probe preparation method and the preparation conditions of colloidal gold immunoassay strip test, the test has the advantages of high specificity, high sensitivity (0.5 µg/mL), simple operation and easy to carry, which can quickly and sensitively detect milk β-Lg allergens in food within 5 minutes. By using β-Lg extraction solution and immunochromatographic test strip, a rapid test kit suitable for the detection of β-Lg allergen in bread, cookies, candies, rice infant formula and other foodstuffs was developed, which provides a rapid and simple method for the semi-quantitative detection of β-Lg in foodstuffs.