Reverse-phase chromatography uses a non-polar stationary phase and a polar mobile phase. Hydrophobic compounds adsorb to the stationary phase, while hydrophilic compounds elute first in the polar mobile phase. This method is widely used in HPLC. Common polar solvents are water, methanol, and acetonitrile. Obtaining a non-polar stationary phase is more challenging, as silica adsorbents are inherently polar. The non-polar phase is prepared by coating silanized silica gel with a non-polar liquid. Reverse-phase chromatography is versatile, with applications in pharmaceutical, food, environmental, and forensic analysis for separating complex mixtures.