Magnetic solid-phase extraction and determination of puerarin in rat plasma using C18-functionalized magnetic silica nanoparticles by high performance liquid chromatography

In the paper, we presented a magnetic solid-phase extraction (MSPE) method based on C18-functionalized magnetic silica nanoparticles for the analysis of puerarin in rat plasma. The approach involves two steps including synthesis of magnetic solid-phase sorbents and bioanalysis. The synthesized magnetic silica microspheres modified with chloro(dimethyl)octylsilane (namely Fe3O4@SiO2-C18) can provide an efficient way for the extraction of puerarin through C18 hydrophobic interaction. The puerarin could be easily enriched using milligram-level Fe3O4@SiO2-C18 sorbents with vibration for 10 min. By means of a magnet, puerarin adsorbed with Fe3O4@SiO2-C18 sorbents was easily isolated from the matrix, and desorbed with CAN. No carryover was observed, and the sorbents could be recycled in our study. The method recoveries were obtained from 85.2% to 92.3%. Limits of quantification and limits of detection of 0.1 μg mL−1 and 0.05 μg mL−1, respectively were achieved. The precision was from 8.1 to 13.7% for intra-day measurement, and from 9.4 to 15.2% for inter-day variation. The accuracy ranged from 94.7 to 106.3% for intra-day measurement, and from 93.3 to 107.8% for inter-day measurement. The MSPE method was applied for analysis of puerarin in rat plasma samples. The results indicated that it was convenient and efficient for the determination of puerarin in biosamples.

► Magnetic solid-phase extraction was developed for determination of puerarin in rat plasma.
► Puerarin adsorbed with Fe3O4@SiO2-C18 sorbents could be simply isolated.
► Method validations were studied.
► The novel extraction method is useful for pharmaceutical analysis.