Layer-by-Layer Assembled Microgels Can Combine Conflicting Properties: Switchable Stiffness and Wettability without Affecting Permeability

Responsive interfacial architectures of practical interest commonly require the combination of conflicting properties in terms of their demand upon material structure. Switchable stiffness, wettability, and permeability, key features for tissue engineering applications, are in fact known to be exclusively interdependent. Here, we present a nanoarchitectonic approach that decouples these divergent properties by the use of thermoresponsive microgels as building blocks for the construction of three-dimensional arrays of interconnected pores. Layer-by-layer assembled poly(N-isopropylacrylamide-co-methacrylic acid) microgel films were found to exhibit an increase in hydrophobicity, stiffness, and adhesion properties upon switching the temperature from below to above the lower critical solution temperature, whereas the permeability of redox probes through the film remained unchanged. Our findings indicate that the switch in hydrophilicity and nanomechanical properties undergone by the microgels does not comprom...