Trace determination and characterization of ginsenosides in rat plasma through magnetic dispersive solid-phase extraction based on core-shell polydopamine-coated magnetic nanoparticles

Enrichment of trace bioactive constituents and metabolites from complex biological samples is challenging. This study presented a one-pot synthesis of magnetic polydopamine nanoparticles (Fe(3)O(4)@SiO(2)@PDA NPs) with multiple recognition sites for the magnetic dispersive solid-phase extraction (MDSPE) of ginsenosides from rat plasma treated with white ginseng. The extracted ginsenosides were characterized by combining an ultra-high-performance liquid chromatography coupled to a high-resolution mass spectrometry with supplemental UNIFI libraries. Response surface methodology was statistically used to optimize the extraction procedure of the ginsenosides. The reusability of Fe(3)O(4)@SiO(2)@PDA NPs was also examined and the results showed that the recovery rate exceeded 80% after recycling 6 times. Furthermore, the proposed method showed greater enrichment efficiency and could rapidly determine and characterize 23 ginsenoside prototypes and metabolites from plasma. In comparison, conventional methanol method can only detect 8 ginsenosides from the same plasma samples. The proposed approach can provide methodological reference for the trace determination and characterization of different bioactive ingredients and metabolites of traditional Chinese medicines and food.