Comparison of Laboratory-Developed and Commercial Monoclonal Antibody-Based Sandwich Enzyme-Linked Immunosorbent Assays for Almond (Prunus dulcis) Detection and Quantification

J Food Sci. 2017 Oct;82(10):2504-2515. doi: 10.1111/1750-3841.13829. Epub 2017 Sep 4.

Abstract

A commercially available monoclonal antibody (mAb)-based direct sandwich enzyme-linked immunosorbent assay (ELISA) kit (BioFront Technologies, Tallahassee, Fla., U.S.A.) was compared with an in-house developed mAb 4C10-based ELISA for almond detection. The assays were comparable in sensitivity (limit of detection < 1 ppm full fat almond, limit of quantification < 5 ppm full fat almond), specificity (no cross-reactivity with 156 tested foods at a concentration of 100000 ppm whole sample), and reproducibility (intra- and interassay variability < 15% CV). The target antigens were stable and detectable in whole almond seeds subjected to autoclaving, blanching, frying, microwaving, and dry roasting. The almond recovery ranges for spiked food matrices were 84.3% to 124.6% for 4C10 ELISA and 81.2% to 127.4% for MonoTrace ELISA. The almond recovery ranges for commercial and laboratory prepared foods with declared/known almond amount were 30.9% to 161.2% for 4C10 ELISA and 38.1% to 207.6% for MonoTrace ELISA. Neither assay registered any false-positive or negative results among the tested commercial and laboratory prepared samples.

Practical application: Ability to detect and quantify trace amounts of almonds is important for improving safety of almond sensitive consumers. Two monoclonal antibody-based ELISAs were compared for almond detection. The information is useful to food industry, regulatory agencies, scientific community, and almond consumers.

Keywords: 4C10; ELISA; MonoTrace; almond; mAb.

Publication types

  • Comparative Study

MeSH terms

  • Allergens / analysis
  • Antibodies, Monoclonal / analysis
  • Cross Reactions
  • Enzyme-Linked Immunosorbent Assay / economics
  • Enzyme-Linked Immunosorbent Assay / methods*
  • Prunus dulcis / chemistry*
  • Reproducibility of Results
  • Seeds / chemistry
  • Sensitivity and Specificity

Substances

  • Allergens
  • Antibodies, Monoclonal