Novel Enzyme-Linked Aptamer Assay for the Determination of Aflatoxin B1 in Peanuts

Abstract

A novel enzyme-linked aptamer assay is reported for the determination of aflatoxin B₁ (AFB₁). AFB₁ can competitively bind with the immobilized biotin-aptamer and release biotin complementary DNA, leading to the gradual fading of the detection system color with increasing of AFB₁ concentration. In the absence of AFB₁, the biotinylated complementary DNA is not be released from the fixed aptamer. Therefore, the enzyme reaction occurs in the detection system. Under the optimized experimental conditions, the proposed method possessed a wide linear range for AFB₁ from 1 to 80?ng/mL (R² of 0.990) with a low detection limit of 0.36?ng/mL. The method was then applied to detect uncontaminated peanuts fortified with different concentrations of AFB₁. The recovery values were from 82.60% to 94.43%, which indicated the proposed method may be used to detect AFB₁ in food and has potential for the development of test kits.