FeMOF-based nanostructured platforms for T-2 toxin detection in beer by a "fence-type" aptasensing principle

In this work, a label-free electrochemical aptasensor for the detection of T-2 toxin was constructed, using gold nanoparticles/Fe-based metal organic framework@graphene oxide (AuNPs/FeMOF@GO) nanocomposites, exonuclease (RecJf), and the "fence-type" structure of aptamer-single stranded DNA (Apt-sDNA) complex as the signal amplification element. Wherein, AuNPs/FeMOF@GO nanocomposite effectively improves the aptasensor performance by improving the electron transfer capacity of the electrode and providing a larger specific surface area to load a large number of Apt-sDNA structures. Meanwhile, the shear effect of RecJf, which was induced by T-2 toxin, further improves the analytical performance of the aptasensor. Under the optimum conditions, the constructed aptasensor shown excellent performance for T-2 toxin detection, with a wide linear range (5.0 × 10^-1 pg·mL^-1-5.0 × 10⁶ pg·mL^-1) and a low limit of detection of 0.19 pg mL^-1. Also, the aptasensor showed high specificity, excellent stability, and available repeatability. What's more, the prepared aptasensor was explored for its application in actual samples and showed good detection results, which provided a new strategy for detecting T-2 toxin in the food and feed. A label-free electrochemical aptasensor for the detection of T-2 toxin was constructed using gold nanoparticles/Fe-metal organic framework@graphene oxide (AuNPs/FeMOF@GO) nanocomposites, exonuclease (RecJf), and the "fence-type" structure of aptamer-single stranded DNA (Apt-sDNA) complex as the signal amplification element.