Fig. 40. (A) Copper-free click reaction carried out between azidobutyl-Q7 and PEG polymer with dibenzocyclooctyne-modified PEG chains. (B) Supramolecular PEGylation of insulin via the Phe^B1 residue (yellow). CB[7] is Q7.¹⁶⁹ Reproduced with permission from ref. 169. Copyright 2016 National Academy of Sciences.