Hydrodynamic Evaluation and Characterization of Capillary Channeled Polymer (C-CP) Fibers as a Stationary Phase in HPLC of Macromolecules

High Performance Liquid Chromatography (HPLC) is the most used analytical technique for the separation of samples in solution. HPLC of has progressed with successive use of new supports such as silica, polysaccharides, monoliths, and organic polymers. Although porous silica phases are very effective in small molecule separations, they suffer from certain drawbacks including pH stability, chemical robustness, high backpressure, and slow mass transfer for macromolecule separations. Thus, the most protein separations are carried out using nonporous, partially porous, and superficially porous phases to overcome mass transfer limitations. As a competing methodology, fiber based polymer support/stationary phases are also developed for protein separations. Capillary-channeled polymer (C-CP) fibers are being developed and characterized in the Marcus laboratory as a platform for variety of separations, predominantly for HPLC separation of macromolecules. C-CP fibers interdigitate to form a network-like structure when they are packed in a column that enables high fluid transport efficiency with low backpressure characteristics. This feature was successfully utilized for macromolecule separations with increased mass transfer characteristics at high linear velocities. In this study polypropylene (PP) C-CP fibers were utilized to evaluate the zone-broadening process of C-CP fiber columns, leading to the optimization of fiber diameter, column dimensions, and packing density (interstitial fraction) for analytical chromatographic separations. The optimized results were applied successfully for the separation of three-protein suite under reversed phase (RP) gradient conditions. Microbore PP C-CP columns were employed for rapid RP HPLC of proteins, evaluating the roles of column length, linear velocity, and radial compression on the separation performance. Nylon-6 C-CP fiber packed columns were characterized as substrates for the downstream processing of bio-macromolecules. An evaluation of adsorption and desorption characteristics of lysozyme on nylon-6 fibers have been investigated with the aim of determining frontal throughput and % yield. The results presented here show lot of promise in developing C-CP fibers as a combined support/stationary phase for bio-macromolecule separations