Comparative analysis of trilobal capillary-channeled polymer fiber columns with superficially porous and monolithic phases toward reversed-phase protein separations.

A trilobal capillary-channeled polymer fiber stationary phase is evaluated for its performance for intact protein separations under reversed-phase high-performance liquid chromatography conditions. The separation quality, operational characteristics, and protein dynamic loading capacity on the fiber phases are compared to commercially-available superficially porous and monolithic columns. The trilobal or "y-shaped" polypropylene fiber phase was employed to separate a synthetic mixture of five proteins (having diverse chemistries and molecular weights). The separation quality was evaluated based on the resolution, peak heights/recoveries, peak widths, and peak areas. The present work illustrates the unique ability to operate at higher linear velocities (47.5 mm/s) while maintaining lower back pressures (∼4 MPa), faster separation times (<8 min), and faster gradient rates using the fiber columns while yielding comparable chromatographic performance to the commercial columns. The separations employing the commercial stationary phases operate at lower linear velocities (∼3.0 mm/s), higher back pressures (∼9 MPa), require longer separation times (10 min), and require slightly higher compositions of organic mobile phase to effect protein elution. Likewise, based on breakthrough loading analysis of lysozyme and bovine serum albumin, the trilobal, polypropylene C-CP fiber column stationary phases demonstrate 3-9X greater binding capacities on a bed volume basis versus the commercial columns.