Cashew ELISA

Enzyme immunoassay for the quantitative determination of Cashew in food.

Background: The Cashew tree (Anacardium occidentale) belongs to the family of Anacardiaceae. With about 18% the fraction of proteins in cashew seed is very high. Some of these proteins, like the vicilin Ana o 1, the legumin Ana o 2 or the albumin Ana o 3 are known for being allergenic. Many of them are heat resistant making them stable to different production processes. For this reason cashew represents an important food allergen.
For cashew-allergic persons hidden cashew allergens in food are a critical problem. Already very low amounts of cashew can cause allergic reactions, which may lead to anaphylactic shock in severe cases. Because of this, cashew-allergic persons must strictly avoid the consumption of cashew containing food. Cross-contamination, mostly in consequence of the production process, is often noticed. This explains why in many cases the existence of cashew residues in food cannot be excluded. For this reason sensitive detection systems for cashew residues in foodstuffs are required.
Cashew ELISA represents a highly sensitive detection system for cashew and is particularly capable of the quantification of residues in cookies, cereals, ice-cream and chocolate.

Description: The Cashew quantitative test is based on the principle of the enzyme linked immunosorbent assay. An antibody directed against cashew proteins is bound on the surface of a microtiter plate. Cashew containing samples or standards are given into the wells of the microtiter plate. After 20 minutes incubation at room temperature, the wells are washed with diluted washing solution to remove unbound material. A peroxidase conjugated second antibody directed against cashew proteins is given into the wells and after 20 minutes of incubation the plate is washed again. A substrate solution is added and incubated for 20 minutes, resulting in the development of a blue colour. The colour development is terminated by the addition of a stop solution, and the colour turns yellow. The yellow colour is measured photometrically at 450 nm. The concentration of cashew is directly proportional to the colour intensity of the test sample.

Product Features:
- The kit contains reagents for 96 determinations;
- Microtiter plate consisting of 12 strips with 8 breakable wells;
- Cashew Standards: 0, 2, 6, 20, 60 ppm;
- ELISA reader at 450 nm;
- Standard range: 2 - 60 ppm;
- Sensitivity analytical: 0.2 ppm.