Surfactants are molecules that contain both hydrophilic and hydrophobic groups, usually in the form of a hydrophilic head and a hydrophobic tail. Surfactants are used in detergents where they can form micelles around hydrophobic dirt molecules and wash them away. Triton X-100 is a surfactant with a hydrophilic polyethylene oxide chain that can be separated on a Primesep D reverse-phase HPLC column based on the number of oxide units in the chain. The mobile phase is water, acetonitrile (MeCN, ACN) and sulfuric acid as buffer. UV detection at 210nm.