Abstract
Poly（ethylene glycol）s（PEGs） have been the most widely used polymer, and PEGylation onto proteins, as well as nanoparticles has become a gold standard technique. PEGs have a long history of safe use in humans, however, induction of anti-PEG antibodies was observed in not only patients, who received PEGylated therapeutics, but also healthy subjects. As many more PEGylated therapeutics have been examined in clinical trials, a better understanding of PEG-related interactions, as well as responses is crucial for development of not only PEGylated therapeutics, but also materials in biomedical fields. The current review summarizes PEG-related specific interactions. Two step interactions are suggested to understand why PEG-conjugates exhibit irreversible bindings, whereas PEGs exhibit only rapid/weak interactions. The current review uncovers PEG-related interactions, and understanding of roles of PEGs will be beneficial for further development of biopharmaceutics.
