Bile salts form amphipathic lipids, micelles that emulsify fats, aiding in their digestion and absorption. A range of different emulsifiers or surfactants are used to emulsify waxes. These detergents emulsify hydrophobic soils and keep soil from redepositing on garments. Thus, the complex serves to emulsify the fats in extracellular fluids. They can help to emulsify compounds that are not usually soluble in water. This procedure uses ultrasonic energy to emulsify the cataract lens.