Convenient and highly efficient adsorption of diosmetin from lemon peel by magnetic surface molecularly imprinted polymers

As a typical bioflavonoid, diosmetin is desirable in the field of natural medicine, healthy food, and cosmetics by anti-cancer, antibacterial, antioxidant, estrogen-like and anti-inflammatory activities, and it comes from a wide range of sources in traditional Chinese medicine like spider fragrance, spearmint and chrysanthemum, as well as in Citrus fruit. However, traditional analytical methods such as silica gel column chromatography face multiple challenges in the selective extraction of diosmetin from biological materials and traditional Chinese medicinal materials. Therefore, it is urgent to develop a new type of absorbent with high efficiency, recyclability and good specificity to diosmetin. In this investigation, a magnetic surface molecularly imprinted polymer (labeled as Diosmetin/SMIPs) was synthesized employing magnetic nanoparticles as the carrier and 4-vinylpyridinyl (4-VP) as the functional monomer by surface imprinting technology. The functional monomer was screened by the binding energy (ΔE) between functional monomers and template molecules via computational simulation. The Diosmetin/SMIPs had a high level of specific recognition and adsorption capability towards diosmetin with a 20.25 mg g-1 adsorption capacity and an imprinting factor (IF) of 2.28. Additionally, it demonstrated excellent regeneration performance with 8 adsorption/desorption cycles. In addition, 91.20%–94.16% of spiked diosmetin was recovered from the lemon peel samples. The strategy of constructing Diosmetin/SMIPs based on computational simulation can effectively enhance the specific adsorption performance of diosmetin. Meanwhile, Diosmetin/SMIPs synthesized by imprinting polymerization showed excellent anti-interference and reusability, and realized efficient targeted extraction of diosmetin from lemon peel samples. The results of this investigation provide a promising adsorbent for selective enrichment of diosmetin from Citrus fruit and complicated materials.