Instrumentation for SFC systems: Different sampling and restriction designs

Different designs of injection and restriction devices for capillary supercritical fluid chromatography (SFC) have been investigated with respect to their practical applicability and usefulness for reproducible and accurate qualitative and quantitative analyses. In combination with a self‐made instrument a fast switching valve is preferable as an injection device compared to a split‐injector, and an integral restrictor made from the end of the fused silica (FS) separation column was superior to a linear restrictor made by coupling a small diameter FS‐column to the separation column.