Detection Method Evaluation for Abrin Toxin in Food Matrices

Introduction: Abrin is an extremely potent bio-toxin produced from the seed of the tropical plant Abrus precatorius, commonly found in the southern U.S. and the Caribbean. Abrin toxin inhibits the synthesis of proteins in the cells of an exposed individual, causing severe illness and cell death. Due to the lethality and ease of accessibility, a screening method for the detection of abrin toxin in foods is necessary for biodefense purposes.

Purpose: This study’s objective was to provide a method combining an optimized extraction and commercially available ELISA kit for the detection of abrin toxin in foods.

Methods: To determine the LOD, six brands each of hot dogs, liquid infant formula, and liquid eggs were fortified at five levels of abrin in quadruplicate and cold stressed overnight. Samples were homogenized with GBS and toxins were extracted via centrifugation. Following extraction, the aqueous layers were analyzed in accordance with the ELISA manufacturer’s instructions. The full scale validation incorporated replicate sets in three fortification levels analyzed in duplicate.

Results: The limit of detection varied with each matrix tested. Liquid infant formula exhibited a 10 ng/g LOD, liquid eggs at 30 ng/g, and hot dogs at 50 ng/g. The sensitivity for the matrices evaluated ranged from 75% (18/24) to 91.7% (22/24). All matrices examined demonstrated 100% specificity (12/12).

Significance: The data from this study suggests that the optimized extraction procedure, combined with the ELISA detection assay, may offer a suitable method for the detection of abrin toxin in foods.