ABSTRACT
High mobile phase flow rates, large internal detector volumes, and low exit pressures contributed to the early technical challenges of interfacing Supercritical Fluid Chromatography (SFC) to sensitive chromatographic detection systems. The chromatographic effluent is introduced directly into the flow cell from the fused silica column and exits the column through a fused silica transfer line, which also serves as a flow restrictor. The primary objective of the FTIR technique is to obtain on-the-fly spectra of the separated mixture. More important, however, is the ease with which supercritical fluid chromatography can be interfaced to gas chromatographic detection systems (SFC). Silanol groups on the fused silica surface become active sites in the capillary column if they are not deactivated. Sample solutes that are sensitive to hydrogen bonding interact with these sites, resulting in reversible and/or irreversible adsorption and poor chromatographic peak shape.
