Metal-organic framework assisted matrix solid-phase dispersion microextraction of saponins using response surface methodology.

An efficient and simple metal-organic framework (MOF) assisted matrix solid-phase dispersion (MSPD) microextraction was developed for the extraction of the five saponins in P. ginseng leaves. The target analyses were detected by ultra high performance chromatography coupled with time-of-flight MS. Experimental conditions for MSPD microextraction were optimized by the Box-Behnken design of the response surface methodology. The optimal conditions were as follows: 20 mg adsorbent, 80% methanol-water solution for elution, 60 s grinding time, and the MOF-808 as the adsorbent. With the final optimized method, the calibration curves for five saponins showed good linearity (R2 > 0.998) within range of 0.01-100 μg/mL. In addition, analytical recoveries ranged from 87.04 to 103.78%, with the RSD below 5%. The limit of detection and LOQ range from 0.087 to 0.114 μg/mL and 0.292 to 0.379 μg/mL, respectively. Compared with the traditional extraction method and published methods, the newly MOF-assisted MSPD extract exhibited higher extraction efficiency, simpler operation, and provided a cleaner extract with low consumption of organic reagents that was applied for rapid evaluation and quality control of active compounds from plants.