The current review presents the advances in PEGylation of drug conjugates based on plentiful literatures up to date. The physiochemical properties of PEG [poly(ethylene glycol)] and advantages of PEGylation for drug conjugates are introduced briefly. The technology of PEGylation of protein and small molecular drug conjugates and application to drug investigation are presented in detail. It is found that PEGylation technology can effectively improve the pharmacokinetic and pharmacodynamic properties of drugs by altering the structures of drug conjugates. It also presents a method to extend the area of clinic application of drug conjugates. The foresight of development and investigation of PEGylation of drug conjugates is also brought forward based on the discussion of advantages and investigation status in quo of PEGylation tech-nology.

Key words: small molecular drug, protein, PEGylation