3. PEGylated Lipids
PEGylated lipids can be applied to liposomal drug formulations to prolong the plasma half-life of the drugs. Coating of the liposomal surface with polyethylene glycol would suppress the uptake of the drug by the reticuloendothelial system, thereby prolonging the half-life of the drug in the plasma. PEG-modified lipids can also be used as emulsifiers and stabilizers of microspheres in aqueous solutions.