Soltes et al. have reported that treating HA with copper(II) salts and ascorbate can result in some degradation of HA, and we also observed that the size of these glycopolymers (as analysed by size exclusion chromatography multi angle light scattering (SEC-MALS)) decreased during the CuAAC reaction, albeit to varying degrees. Starting from a number average molecular mass Mn of 137 kDa for HA-g-propargyl (Table ), the CuAAc reactions provided glycopolymers with Mn = 22 kDa for HAg-Le x , 60 kDa for HA-g-Gb3, 40 kDa for HA-g-Lac L and 84 kDa for HA-g-Lac H (Figure and Table ).