Double affinity based molecularly imprinted polymers for selective extraction of luteolin: A combination of synergistic metal chelating and boronate affinity

This study addresses opportunities for large-scale extraction of health-beneficial compounds from agricultural waste peanut shell samples. We focus on preparing a novel metal-chelating and boronate-affinity double affinity molecular imprinted polymers (MB-DMIPs) adsorbent and developing a new method to resolve current problems in enrichment of luteolin (LTL) from peanut shell samples. Boronate-affinity technique can produce a synergistic effect with metal oxide to effectively improve the adsorption capacity for LTL. Compared to the single affinity molecular imprinted polymers (M-SMIPs and B-SMIPs), the MB-DMIPs possessed stronger specificity, higher sensitivity, and better efficiency. The enrichment capacities and selectivities for LTL with the MB-DMIPs were studied in detail, after enriched, LTL was detected by HPLC. Under the optimal conditions, the maximum adsorption capacity reaches 12.42 mg g(-1), and the imprinted factor is 2.89. The detection limit is 0.021 mg L-1, quantitative limit is 0.067 mg L-1, and the recoveries are between 85.5 and 103.1% (the relative standard deviations are less than 3.2%, n = 3). This work will provide a new research scheme for extraction and purification of bioactive components from agricultural wastes.