High affinity aptamers for ultra-sensitive detection of aflatoxin B1 in milk and groundnut samples with label-free photo-electrochemical aptasensor

Abstract

Aflatoxin B₁ is a potent liver toxin and easily accumulated in foodstuff and environment via the food chain, subjecting high hazards to human health. Rapid initial diagnosis is one of the most impressive monitoring procedures to overcome the potential hazards. Nevertheless, the classical approaches confront many limitations, like low specificity and sensitivity and complicated procedures. Herein, a photo-electrochemical aptasensor based on sensitized poly(dopamine)@functionalized multiwall carbon nanotube/titanium dioxide (PDA@f-MWCNTs/TiO₂ NTs) was designed to detect aflatoxin B₁ in real samples (e.g. groundnut and milk). The mentioned label-free biosensing platform not only needed simple operations but also presented outstanding reusability, storage stability, reproducibility, and specificity simultaneously. This suggested strategy could sensitively and selectively detect aflatoxin B₁ with dynamic range of 0.005-50 ng/mL and a low limit of detection 1 pg/mL. This procedure could provide the bright prospect for detection of aflatoxin B₁ residues in foodstuff.

Keywords: Aflatoxin B(1); Aptasensor; Foodstuff; Label-free; Photo-electrochemical.