Introducing Distinctly Different Chemical Functionalities onto the Internal and External Surfaces of Mesoporous Materials

The ins and outs of it: The external and internal surfaces of mesoporous materials can be modified independently by exploiting the wetting behavior of the pores modified with a hydrophobic activated monolayer. To demonstrate the principle, porous silicon photonic crystals were modified with ligands promoting cell adhesion on the top of the crystal and with different functionalities on the inside of the crystal.