RESUMO
Polyethylene glycol(PEG) with good hydrophilicity and flexibility can improve pharmacokinetic and pharmacodynamic properties of the nano-preparation,so PEG modification in the surface of nano-preparation can increase the in vivo residence time and concentration of drugs.At present,the targeted nano-preparation with PEG modification has become a research hotspot in the field of pharmaceutics.In this paper,the physical and chemical methods of PEG modification in targeted nano-preparation was summarized,which includes physically inserting PEG-lipid derivatives in nanostructure of targeted nano-preparation or modifying PEG with targeted nano-preparation.In addition,the influence of PEG parameters (molecular mass,modified density and spatial conformation) on properties of targeted nano-preparation was also discussed,which is important to preferably structure PEGylated targeted nano-preparation.