Separation of hydrophobic metabolites using monolithic silica column in high-performance liquid chromatography and supercritical fluid chromatography.

Monolithic silica columns have very low back-pressures and offer several advantages over conventional columns packed with spherical particles, such as high separation efficiency and rapid analysis. In this review, we report the applicability of monolithic silica columns for the analysis of complex hydrophobic metabolites. We have used monolithic columns in HPLC and developed a separation technique for the high-speed and high-resolution analysis of the geometric analogs of natural polyprenols. We also used monolithic columns in supercritical fluid chromatography for the successful separation of the structural isomers of carotenoids after deciding the analytical conditions that were suitable for this separation and have developed a method for profiling biological samples containing complex matrices. We have proved that excellent resolution can be obtained by connecting a number of monolithic columns in series.