Aptamer based point of care diagnostic for the detection of food allergens

Sarah Stidham,Valerie Villareal,Olivia Alley,Lucas Yoder,Adi Gilboa-Geffen,Hugh Sampson,David Fleischer,Jonathan Spergel,Wayne Shreffler,Vasant Chellappa

doi:10.1038/s41598-022-05265-0

Abstract

Aptamers, due to their small size, strong target affinity, and ease of chemical modification, are ideally suited for molecular detection technologies. Here, we describe successful use of aptamer technology in a consumer device for the detection of peanut antigen in food. The novel aptamer-based protein detection method is robust across a wide variety of food matrices and sensitive to peanut protein at concentrations as low as 12.5 ppm (37.5 µg peanut protein in the sample). Integration of the assay into a sensitive, stable, and consumer friendly portable device will empower users to easily and quickly assess the presence of peanut allergens in foods before eating. With many food reactions occurring outside the home, the type of technology described here has significant potential to improve lives for children and families.

Highlights

Aptamers, due to their small size, strong target affinity, and ease of chemical modification, are ideally suited for molecular detection technologies
To determine the affinity of each optimized aptamer for Ara h 1, a major peanut allergen and the most abundant allergen in peanut (12–16% of the total protein content)[26,27], increasing amounts of purified unlabeled Ara h 1 were incubated with each aptamer and analyzed using fluorescence polarization (FP) to screen for binding affinity (Fig. 1a)
For detection of peanut antigen, an aptamer, P1-16, was identified and binding affinity determined for pure peanut protein Ara h 1 ( Kd ~ 54 ± 5.5 nM) and Ara h 1 in peanut butter and peanut flour ( Kd ~ 141 ± 21.9 ppm, and 144 ± 31.4 ppm, respectively; Fig. 1)

Summary

Introduction

Due to their small size, strong target affinity, and ease of chemical modification, are ideally suited for molecular detection technologies. Since development of the in vitro systematic evolution of ligands by exponential enrichment (SELEX) selection process in 1990, aptamers have been designed to selectively bind diverse targets, including RNA, DNA, and other small molecules and compounds[2,3,4] These use cases have supported their development as valuable tools for fundamental research, therapeutic applications, and as sensors in molecular diagnostic devices[3,5]. Due to their high affinity, small size, and ease of chemical modification, aptamers have been suggested as a superior reagent for molecular target recognition.

Objectives

Methods

Results

Conclusion