ZIF-8@SiO2 based novel dispersive solid-phase filter extraction technique for the purification of laminarin and fucoidan from undaria pinnatifida.

[Display omitted] • Developed a novel dispersive solid phase filtration extraction pretreatment technique. • A large particle size of ZIF-8@SiO 2 was prepared as the adsorbent. • Rapidly and accurately analysis of seaweed polysaccharides in undaria pinnatifida. Laminarin and fucoidan belong to seaweed polysaccharides, which are abundant in kelp, such as undaria pinnatifida, and have a variety of beneficial pharmacological activities. This study developed a dispersive solid-phase filter extraction (DSPFE) method by combining the high mass transfer efficiency of traditional dispersive solid-phase extraction (DSPE) with the timesaving and convenient advantages of filter solid-phase extraction (FSPE). Although the surface interactions enable ZIF-8 to separate large molecules, the small particle size of ZIF-8 generates ultrahigh pressures during solid-phase extraction (SPE). Hence, a large particle size of ZIF-8@SiO 2 can be obtained by growing ZIF-8 on SiO 2. Using ZIF-8@SiO 2 as the adsorbent for DSPFE combined with high-performance size exclusion chromatography (HPSEC), the conditions of vortex-assisted DSPFE were optimized to realize the economic (adsorbent amount: 5 mg), rapid (extraction time: 10 min), and efficient (recovery: 88.5–91.1%) extraction and analysis of laminarin and fucoidan in undaria pinnatifida. The adsorption process followed Freundlich isotherm (R2 ≥ 0.9792) and pseudo-second-order kinetics (R2 ≥ 0.9870). The proposed method showed good linearity (0.01–2 mg/mL, R2 ≥ 0.9990), limit of detection (0.027–0.114 mg/mL), limit of quantitation (0.089–0.379 mg/mL), accuracy (93.4–104.7%), and precision (2.2–5.6%). [ABSTRACT FROM AUTHOR]