Novel strategy for the facile enrichment of isopentenyl pyrophosphate in rat plasma via Ti4+-immobilized polydopamine@Fe3O4 core–shell microspheres

In this paper, a facile extraction strategy is reported for the analysis of isopentenyl pyrophosphate, a key isoprenoid, based on magnetic core–shell microspheres with Ti 4+ ion exterior walls coupled with liquid chromatography and tandem mass spectrometry. Because of their excellent hydrophilicity and biological compatibility, the polydopamine@Fe 3 O 4 -Ti 4+ microspheres display ideal isopentenyl pyrophosphate extraction efficiency. The technique includes three steps: sample loading, nonphosphate washing, and phosphate elution. Moreover, the microspheres can be regenerated by thorough washing with a specific solvent and can be reused multiple times. The liquid chromatography with tandem mass spectrometry separation was performed on a Welch Ultimate® XB-C 18 column with a total chromatographic analysis time of 5 min; the analytical recovery was 98.52%. The proposed method was used to determine the isopentenyl pyrophosphate concentration in rat plasma samples collected from the Shanghai Chest Hospital. The results indicate the prospective value of the as-made microspheres for the sensitive and selective enrichment of phosphate compounds in complicated matrices.