SUPER CRITICAL FLUID CHROMATOGRAPHY: AN OVERVIEW

Supercritical Fluid Chromatography (SFC) is a form of normal phase chromatography, first used in 1962.SFC typically utilizes carbon dioxide as the mobile phase; therefore the entire chromatographic flow path must be pressurized. Because the supercritical phase represents a state in which liquid and gas properties converge, supercritical fluid chromatography is sometimes called convergence chromatography. Supercritical fluid chromatography is one of the most important column chromatography methods after gas chromatography (GC) and high-performance liquid chromatography (HPLC). Supercritical fluids combine useful properties of gas and liquid phases. The characteristic properties of a supercritical fluid are density, diffusivity and viscosity.SFC, the sample is carried through a separating column by a supercritical fluid where the mixture is divided into unique bands based on the amount of interaction between the individual analytes and the stationary phase in the column. As these bands leave the column, their identities and quantities are determined by a detector SFC is a hybrid of gas and liquid chromatography because when the mobile phase is below its critical temperature and above its critical pressure, it acts as a liquid, so the technique is liquid chromatography (LC) and when the mobile phase is above its critical temperature and below its critical pressure, The instrumentation that is required for supercritical fluid chromatography is versatile because of its multi-detector compatibility.SFC has been applied to wide variety of materials including natural products, drugs, foods, pesticides, herbicides, surfactants, polymers and polymer additives, fossils fuels, petroleum, explosives and propellants.