A fluorescence aptasensor based on controlled zirconium-based MOFs for the highly sensitive detection of T-2 toxin

T-2 toxin is one of class A trichothecene mycotoxins produced by Fusarium, presenting genotoxic, cytotoxicity, and immunotoxicity for animals and humans. Therefore, It is urgent to establish a rapid test method with high sensitivity, good selectivity and reliability. In this research, by adjusting the synthesis conditions, a kind of NH₂-UiO-66 with high quenching efficiency was screened out. On this basis, we constructed a novel fluorescence sensor via Cy3-labeled aptamer (Cy3-aptamer). With the help of π-π interaction, hydrogen bond and coordination, NH₂-UiO-66 could adsorb and quench the fluorescence of Cy3-aptamer based on FRET and PET. In the presence of T-2 toxin, it recognized and bound to Cy3-aptamer, leading to the disintegration of the NH₂-UiO-66/Cy3-aptamer compound. As the energy transfer process was blocked, the fluorescence intensity was restored, enabling a highly sensitive response to T-2 toxin. There was a good linear correlation between fluorescence intensity and T-2 toxin concentration in the range of 0.5-100 ng ml ^-1. The LOD of this fluorescence aptasensor was 0.239 ng ml^-1 (S/N = 3). Besides, the recoveries of milk and beer were 89.86-108.99% (RSD = 2.0-2.6%) and 92.31-111.51% (RSD = 2.3-2.9%), respectively. The fluorescence aptasensor exhibited advantages of excellent analytical performance, convenient operation procedure and good selectivity. Predictably, the aptasensor was supposed to detect antibiotics and other pollutants, describing an intriguing blueprint and potential application prospect in food safety, biochemical sensing and environmental conservation.