The use of supercritical fluid chromatography is a green alternative to traditional HPLC, with the use of CO2 taking the place of organic solvent as the mobile phase. CO2 has benefits for cost, and health & safety, as well as faster, cleaner sample recovery during sample purification. Other advantages of supercritical fluids include low viscosity with liquid-like densities, for higher solubility and increased column loading. The low viscosity and high diffusion lead to faster separations and faster extractions.