Wrinkled hydrogel surfaces with modulated surface chemistry and topography: evaluation as supports for cell growth and transplant

We report a straightforward procedure to simultaneously functionalize hydrophobic PC supports with vinylpyrrolidone (VP)-based hydrogels with both variable ionic load as well as surface topography, forming wrinkles. The strategy involves three consecutive steps, i.e. a) contact of the polymeric support (PC) with a photopolymerizable vinylic solution, b) UV curing of the solution and finally c) surface detachment of the formed polymer network, upon swelling. Interestingly, a wrinkled hybrid PC/hydrogel interface remains after this detachment. Several experimental parameters allowed us to tune the wrinkle characteristics such as amplitude and period. These include the contact time between the support and the photopolymerizable solution, or the solvent (type and amount) included in the monomer mixture. Equally, the nature of the additional ionic methacrylate monomers (M) employed plays a key role on the final topography. According to Confocal Raman Microscopy results, a monomer diffusion into the PC substrat...