Three-Dimensional Ordered Macroporous Magnetic Inverse Photonic Crystal Microsphere-Based Molecularly Imprinted Polymer for Selective Capture of Aflatoxin B1

Development of an efficient detection method to monitor residual mycotoxins in food is very important to ensure food safety, but the complex food matrix seriously affects the detection sensitivity and accuracy. Here, using a three-dimensional ordered macroporous magnetic inverse photonic crystal microsphere (MPCM) as the supporting material, a molecularly imprinted polymer (MIP) that can selectively recognize aflatoxin B1 (AFB1) was synthesized through the dummy template imprinting strategy. The MPCM@MIP prepared by employing 5,7-dimethoxycoumarin as the template and methacrylic acid as the functional monomer displayed selectivity toward AFB1 (imprinting factor of 1.5) and could be used as a solid-phase extraction material. By coupling with high-performance liquid chromatography, an analytical method targeting AFB1 was established and displayed a wide linear range of 5-1000 ng/mL with a low detection limit of 0.4 ng/mL. The method showed a good recovery rate of 73-92% in AFB1-spiked soy sauce and vinegar samples. Moreover, the MPCM@MIP could be separated from the sample solution easily because of its magnetic performance, displaying a promising future not only in the enrichment of AFB1 to improve the detection sensitivity and accuracy but also in the removal of AFB1 from food and environmental samples.