Polyethylene glycol (PEG), also referred to as polyethylene oxide (PEO) or polyoxyethylene (POE), is a synthetic polyether compound that has a wide range of applications in various fields, such as industrial manufacturing and medicine. PEG is derived from petroleum and its structure is typically represented as H−(O−CH2−CH2)n−OH, where n represents the number of repeating units of the ethylene glycol backbone. The molecular weight of PEG determines whether it is referred to as PEG, PEO, or POE.PEG is a water-soluble polymer that can also dissolve in methanol, ethanol, acetonitrile, benzene, and dichloromethane, while it is insoluble in diethyl ether and hexane. PEG can be attached to hydrophobic molecules to produce non-ionic surfactants.PEG is a widely used material in drug delivery systems and tissue engineering scaffold formation due to its excellent biocompatibility. It can be degraded by hydrolysis and enzymatic processes. Moreover, PEG exists in various structures, including linear, branched, comb-like, and star macromolecules.Polyethylene glycol (PEG) is a versatile polyether that finds applications in various fields, especially in medicine. PEG is also known as polyethylene oxide (PEO), with the distinction being that PEG refers to ethylene oxide macromolecules with molecular weights less than 20,000 g/mol, while PEO is used for those with values above 20,000 g/mol.