A Brief Review of Interfacing Supercritical Fluid Chromatography with Mass Spectrometry

In the past decade, supercritical fluid chromatography (SFC) has experienced a steady growth in acceptance, particularly in pharmaceutical and chemical laboratories. Compared to HPLC, SFC offers better selectivity and shorter analysis time because of the low viscosity and high diffusivity inherent to supercritical fluids. Due to the intrinsic universality, sensitivity, and specificity of MS, SFC MS readily lends itself as an attractive complement to RPLC MS. This brief review deals primarily with the applications of SFC MS to show the versatility and broad applicability of this hyphenated technique, with a heavy emphasis on pharmaceutical related applications.

Introduction
In the past decade, supercritical fluid chromatography (SFC) has experienced a steady growth in acceptance, particularly in pharmaceutical and chemical laboratories. In SFC, a “supercritical” fluid, most commonly CO2, in combination with one or more polar organic solvents, such as alcohols, is used as mobile phase. While CO2 itself is relatively non-polar, the addition of polar organic solvents enables the mobile phase to retain the
polarity and solvating power of the polar organics. Compared to HPLC, SFC offers better selectivity and shorter analysis time due to the low viscosity and high diffusivity inherent to supercritical fluids [1]. The ongoing
acetonitrile (ACN) shortage has also stimulated an elevated interest in employing SFC as a possible alternative to the industry-dominating, ACN-reliant reversed phase LC (RPLC).