Abstract: In this paper, using mesoporous silica nanoparticles (MSN) to enrich the signal probe and using the T-2 toxin aptamer as a recognition probe and a switch to control the signal probe, a rapid label-free technique for the quantitative detection of T-2 toxin was proposed based on the relationship between the signal intensity and the content of the target toxin. In the detection system, the target T-2 toxin could specifically bind to its aptamer, releasing the signal probe. The results showed that when this method was applied to corn, barley and wheat samples, the spiked recoveries of T-2 toxin were in the range between 85.8% and 111.4% with relative standard deviation (RSD) less than 4.6%, indicating that this method has good accuracy and repeatability. The method was sensitive with a limit of detection of 1.25 ng/mL and showed a good linearity in the concentration range of 0–50 and 50–250 ng/mL. Compared with the traditional method, this novel method was more rapid, simpler and cheaper and allowed sensitive and quantitative detection of T-2 toxin with a wider linear range.

Key words: T-2 toxin; aptamer; mesoporous silica nanoparticles; label-free; fluorescence spectroscopy