Supercritical HPLC is high-performance liquid chromatography adapted to use supercritical fluids, usually carbon dioxide with modifiers, as the mobile phase, bridging HPLC and supercritical fluid chromatography. It is applied to compounds that are difficult to separate by conventional reversed-phase HPLC or too thermally labile for gas chromatography, such as complex lipids, carotenoids, and chiral flavour compounds. The low viscosity of supercritical fluids permits faster separations at lower pressure drops than liquid mobile phases. In food analysis it is a specialist tool for lipid profiling and natural-product characterization.