Polyoxyethylene castor oil derivatives are complex mixtures of various hydrophobic and hydrophilic components.
In castor oil the hydrophobic constituents comprise about 83% of the total mixture, the main component being glycerol polyethylene glycol ricinoleate. Other hydrophobic constituents include fatty acid esters of polyethylene glycol along with some unchanged castor oil. The hydrophilic part (17%) consists of polyethylene glycols and glycerol ethoxylates.
In approximately 75% of the components of the mixture are hydrophobic. These comprise mainly fatty acid esters of glycerol polyethylene glycol and fatty acid esters of polyethylene glycol. The hydrophilic portion consists of polyethylene glycols and glycerol ethoxylates.
Polyoxyethylene castor oil derivatives are used in a variety of oral, topical and parenteral pharmaceutical formulations.