Modifying of magnetic UiO-66-NH2 as a new nanosorbent by thermo-alkali-hydrolysis technology for highly efficient enrichment and determination of quercetin in apple peel
Ruimiao Chang, Huichun Wang, Shumian Liu, Yijing Dong, Guangbin Zhang, Anjia Chen, Ruiping Zhang, Yong Li
Abstract
For rapid separation of quercetin from apple peel, a novel magnetic nanomaterial was prepared by a simple and economical thermal alkaline hydrolysis method in this work. This magnetic nanomaterial was obtained by mixing magUiO-66-NH2 (magnetic University of Oslo 66-NH2) with 0.05 mol·L-1 KOH aqueous solution and then heated, and was named magUiO-66-NH2-MH0.05 (magUiO-66-NH2-mixed heating0.05), which has better magnetic properties, thermal stability, pore capacity and average pore size than magUiO-66-NH2. The obtained magUiO-66-NH2-MH0.05 had strong adsorption capacity for quercetin, and the maximum adsorption capacity was 65.30 mg·g−1. MagUiO-66-NH2-MH0.05 tends to be monolayer-layer adsorption for quercetin, and electron sharing or transfer may occur during the adsorption process. Compared with naringenin, naringin and gallic acid, magUiO-66-NH2-MH0.05 showed good recognition ability for quercetin, and the recoveries were good. After 7 cycles, the adsorption capacity of magUiO-66-NH2-MH0.05 for quercetin was 96.3 % of the initial adsorption capacity. A magnetic solid-phase extraction method coupled with High-Performance Liquid Chromatography based on magUiO-66-NH2-MH0.05 was successfully used for rapid separation and determination of quercetin in apple peel. This study will help to discover the experimental law of the treatment of UiO-66-NH2 nanomaterials by hot alkaline hydrolysis, reveal the reaction mechanism, and expand the application of UiO-66-NH2 nanomaterials in food analysis.