Comparable trends were also reported for poly(diethylaminoethyl methacrylate) (PDEAEMA) brushes, although associated with overall reduced swelling considering their increased hydrophobicity . Interestingly, correlation with in situ attenuated total internal reflection FTIR enabled to directly evidence changes in brush protonation as a function of pH. Similarly, Geoghegan et al. reported the pH responsive behaviour of PDEAEMA brushes, associated with moderate swelling compared to PDMAEMA and a sharp swelling upon protonation, below the pKb of this polyelectrolyte brush .