Preparation of molecularly imprinted polymers for the selective extraction and purification of hesperidin from orange peels

Orange peels are a common by-product in the global food processing industry, leading to resource wastage and environmental pollution. They are rich in hesperidin, a flavonoid with multiple pharmacological and biological activities, possessing significant economic value. Based on this, in this study, a one-pot method was developed to create hesperidin MIPs for selective separation and purification of hesperidin from waste orange peels. To obtain the optimal MIPs, the best functional monomer was first determined through computer simulations and spectroscopic scanning, and the synthesis process was optimized. The characterization results demonstrated that the obtained MIPs, due to the presence of the functional monomer 2-vinylpyridine (2-VP), effectively adsorbs hesperidin through hydrophobic interactions and π-π stacking between the benzene ring and pyridine ring, achieving an adsorption capacity of 74.18 mg/g. MIPs exhibited excellent selectivity in the presence of two structural analogs, naringin and neohesperidin, and the imprinting factor reached 2.01. Furthermore, the MIPs exhibited excellent selectivity in the presence of structurally similar compounds within a complex matrix. In practical applications using MIPs as the adsorbent, the maximum extraction efficiency of hesperidin can reach 73.88 %, with the purity of extracted hesperidin reaching 81.24 %. After seven consecutive adsorption-desorption cycles, the adsorption capacity of MIPs for hesperidin decreased by only 1.55 mg/g. This research provides a simple and efficient integrated strategy for the separation and purification of hesperidin from orange peel waste, with great potential for commercial application.