Effect of Phase Ratio and Column Type on Retention in SFC (Supercritical Fluid Chromatography)

摘要

Extensive discussion continues regarding the relative merits of capillary and packed columns for supercritical fluid chromatography (SFC). Columns of interest typically include commercially available 50- mu m i.d. capillaries having an /approximately/0.25- mu m film thickness and packed columns containing 3- mu m or 5- mu m diameter developed for HPLC. It has been demonstrated that packed columns can offer advantages in terms of speed because the properties of fluids high linear velocities to be utilized, but the lower pressure drop with open tubular capillary columns allows a greater number of effective theoretical plates through the use of longer columns. Much discussion has centered about the comparison of columns under various operating conditions of practical interest (e.g., pressure programming for capillaries or isobaric operation for packed columns). It is the purpose of this report to show the importance of column phase ratio (i.e., the ratio of stationary to mobile phase volumes. V(sub s) and V(sub m), respectively in the selection of columns for specific SFC applications. (ERA citation 13:045444)