Walnut Allergen ELISA kitrequest-ifu

Competitive Enzyme immunoassay

Product Code
WJ4-EK-96    96 tests
WJ4-EK-48    48 tests

Total Assay time
30 Minutes


Incubation Times:
10-minute steps for sample incubation, conjugate incubation, and substrate incubation.

Limit of Detection:
0.22 ppm

Range of Quantification:
1 to 40 ppm

Make an Enquiry regarding Walnut Allergen ELISA kits

Walnut Allergen ELISA kit

Walnuts are used extensively in foods, especially in baked goods, and are the leading cause of allergic reactions to Tree nuts in the US. Walnut and Pecan are cross-reactive in many allergic individuals, but, compared to other detection methods, BioFront’s MonoTrace ELISA kit shows a higher degree of specificity to Walnut.

BioFront Technologies has developed the first comprehensive line of monoclonal antibody-based ELISA assay kits (MonoTrace ELISAs) for the detection of food allergen contamination in various food samples and environmental surfaces. The MonoTrace Walnut ELISA incorporates the use of a precisely defined set of handpicked monoclonal antibodies selected after a rigorous screening process for their ability to:
Target a highly stable Walnut allergen resistant to food processing effects
Recognize a carefully selected target protein to eliminate cross-reactivity and reduce the possibility of ‘false positive’ results
Perform well in a wide variety of food products with negligible food matrix interference


The assay exhibits strong reactivity to walnut (Juglans regia). Pecan (0.0023%), adzuki bean (0.002%), rapeseed (0.0014%),and nutmeg (0.0018%) were minimally reactive in the assay. At concentrations as high as 100,000 ppm, no cross-reactivity was observed within the other matrices(including tree nuts, legumes, seeds, flour, meats and spices) tested using the MonoTrace Walnut ELISA kit.


The MonoTrace Walnut ELISA kit is suitable for the qualitative or quantitative detection of walnut within cereal, cake, ice cream, chocolate and cookies. Chocolate and ice cream extractions required the addition of 5% (w/v) non-fat dry milk (NFDM) to the extraction buffer. This extraction additive is needed for samples containing polyphenols, which include: chocolate, fruits, teas, coffee, red wine and soybean as well as others not listed here. Recoveries were acceptable, according to current AOAC guidelines (J. AOAC Int. 2012). In summary, walnut protein was efficiently extracted and detected from diverse food matrices.

Other matrices may also be suitable for the MonoTrace Walnut ELISA kit. Contact BioFront Technologies technical support (support@biofronttech.com) for assistance to determine whether your matrix-of-interest has been validated (cross reactivity & recovery). An internal validation using a walnut-spiked sample is recommended to ensure that walnut protein is efficiently recovered before qualitative or quantitative results are obtained from the kit.

Walnut Allergen ELISA kit