Veratox® VIP for Walnut

• Features an optimized antibody combination and extraction procedure for high specificity to all types of walnut protein, particularly further-processed walnut.
• Highly sensitive, quantifying walnut protein down to 0.15 ppm, aligned with most up-to-date industry guidelines.
• Rapid and easy to use, with a 30-minute time to result; a simple testing procedure consistent across sample types; and ready-to-use, non-hazardous reagents.

The Veratox VIP for Walnut test is a sandwich enzyme-linked immunosorbent assay (S-ELISA). This assay is validated to detect three primary allergenic proteins in walnuts. Walnut protein is extracted from samples with a buffer solution by shaking in a heated water bath, followed by centrifugation or filtration. Extracted walnut protein is sampled and added to antibody-coated wells (capture antibody), where it binds to the antibody during an incubation. Any unbound walnut protein is washed away and a second antibody (detector antibody), which is enzyme labeled, is added. The detector antibody binds to the already bound walnut protein. After a second wash, substrate is added. Color develops as a result of the presence of bound detector antibody. Red Stop Solution reagent is added and the color of the resulting solution is observed. The test is read in a microwell reader to yield optical densities (OD). The OD of the controls form a standard curve, and the sample OD are plotted against the curve to calculate the concentration of walnut protein.