Pressurised Solvent Extraction is an automated extraction technique that uses organic solvents to extract solid or semi-solid samples under elevated temperature (50–200 °C) and pressure (1000–3000 PSI).
Increased temperature reduces the intermolecular forces (van der Waals forces, hydrogen bonding, dipole interactions between analytes and active sites of the sample matrix), thereby enhancing extraction efficiency.
Since the solubility of liquids is much higher than that of gases, applying pressure allows solvents to be heated above their normal boiling points.