Adsorptive and responsive hybrid sponge of melamine foam and metal organic frameworks for rapid collection/removal and detection of mycotoxins

Mycotoxins have been regarded as one of the most severe threatens to food safety and environment, however, conventional detection methods are limited by low collection efficiency and tedious detection procedures. In this work, adsorptive and responsive hybrid sponge was prepared by integrating porous fluorescent Zr-LMOF (luminescent metal-organic framework) and robust melamine sponge for simultaneous collection/removal and detection of mycotoxins. The hybrid sponge achieved high load capacity of 15.8 mg g(-1) within 10 min and worked well in a wide range of pH and temperatures. The fluorescence of the hybrid sponge was efficiently quenched by AFB1 in the aqueous water in 10 min due to the hierarchical pore structure enabled absorbent target interaction. This simple, robust and low-cost dual functional hybrid sponge enabled the detection with relatively low LOD of 1.6 ppb and wide linear range of 31.2 ppb-15.6 ppm. Additionally, AFB1 in water was quickly absorbed by the Zr-LMOF crystals on the melamine microfibers with the removal efficiency reached as high as 90%. The removal efficiency towards other mycotoxins including aflatoxin B2, aflatoxin G1, aflatoxin G2, aflatoxin M1 and ochratoxin A also reached 80%. Overall, this low-cost, robust and elastic hybrid sponge has great potential in the construction of novel sensors for practical applications to ensure environmental and agricultural safety.