A fluorescent immunochromatographic strip test using Quantum Dots for fumonisins detection

Abstract

A fluorescent immunochromatographic strip test (ICST) based on the use of Quantum Dots (QD) was developed and applied to detect fumonisins in maize samples. A limit of detection for fumonisin B1 of 2.8µgL−1 was achieved, with an analytical working range of 3–350µgL−1, corresponding to 30–3500µgkg−1 in maize flour samples, according with the extraction procedure. The time required to perform the analysis was 22min, including sample preparation. Recovery values in the range from 91.4% to 105.4% with coefficients of variation not exceeding 5% were obtained for fortified and naturally contaminated maize flour samples. To evaluate the possible improvements due to the use of QD for ICST technology, we performed a direct comparison of the proposed QD-ICST to a gold nanoparticles- and a chemiluminescent-ICST previously developed for fumonisins detection, in which the same immunoreagents were employed.