What are the properties of polyethylene glycol (PEG)?

Being uncharged, PEG is highly hydrated and resistant to protein adsorption. This property allows for targeted cell attachment by incorporating specific signaling molecules while preventing the attachment of unwanted cells. The hydroxy end groups of PEG chains enable easy attachment of reactive groups, typically acrylic (PEGDA) or methacrylic (PEGDMA). PEG is not susceptible to hydrolysis, and only ester groups are cleavable. Longer PEG chains result in more flexible materials, while the rate of mass loss decreases with increased hydrophobicity. PEG possesses several defining characteristics: it is non-toxic, colorless, odorless, inert, and non-volatile. Additionally, it exhibits high solubility in organic solvents like benzene and chloroform. Although varying its molecular weight can slightly alter its shape and physical appearance, these properties remain consistent across different forms of PEG.