Impact of Size Heterogeneity of Core-Shell Packing Materials on Chromatographic Separation of Large Biomolecules

The effect of particle size heterogeneity of core-shell stationary phases on the efficiency of chromatographic separation of large biomolecules was studied. It was shown that the column efficiency was affected significantly by the breadth of particle size distribution. The chromatographic efficiency decreased as the heterogeneity of particle sizes increased. Although the absolute decrease of separation efficiency was affected by the linear velocity, u, of the eluent, the relative change of HETP was independent of u in the practical range of eluent velocities. The results showed that the affect of particle size distribution was the highest in case of fully porous phases, and it decreased as the diameter of the inner core decreased. It was shown that, in the usual range of particle size heterogeneity of core-shell phase, the peak capacities did not change significantly even at high eluent velocities.