A novel multimode biosensor for sensitive detection of AFB1 in food based on Mxenes nano enzymes

In this work, Ti 3 C 2 nano-enzymes (Ti 3 C 2 NEs) materials with simulated peroxidase activity and fluorescence quenching properties were prepared. Then Ti 3 C 2 NEs was functionalized using 6-carboxyfluorescein (FAM) labeled Aflatoxin B 1 (AFB 1 ) aptamers to construct a novel multimode nano enzyme biosensor for the detection of AFB 1 in peanuts. Based on the fluorescence quenching characteristics and the superior simulated peroxidase activity of Ti 3 C 2 NE S and the specific binding of the aptamer to AFB 1 , the sensitive and rapid fluorescence/colorimetric/smart phone detection of AFB 1 have been achieved, with detection limits of 0.09 ng mL −1 , 0.61 ng mL −1 and 0.96 ng mL −1 , respectively. The analytical method provided can not only detect AFB 1 in multiple modes, but also has a wider detection range, lower limit of detection (LOD) and better recovery rate, and can achieve on-site accurate detection of AFB 1 content in peanuts, which has great application potential in the field of food quality testing.