This suggests rearrangement of the brush structure and condensation of the complex close to the surface, in these more flexible and structurally dynamic coatings. Overall, the thickness of the resulting complexes remained unaltered compared to the pristine low density brush. The architecture of PMETAI RNA-brush complexes was more strikingly impacted compared to PDMAEMA equivalents. Despite comparable levels of RNA oligo absorption (as monitored by SPR ), the SLD of PMETAI brushes increased more significantly upon RNA complexation than for PDMAEMA brushes with comparable grafting density and thickness brushes (Figure ).