Patterning and impregnation of superhydrophobic surfaces using aqueous solutions

We report a solvent-assisted approach to the patterning and impregnation of porous superhydrophobic coatings that permits the use of entirely aqueous solutions. This approach permits immobilization of proteins and enzymes, creating opportunities to decorate superhydrophobic surfaces with hydrophilic domains and channels that can capture aliquots of aqueous media, guide and mix aqueous solutions, and chemically process streams of organic molecules. Because this approach does not require destruction of non-wetting features, it can also be used to transfer highly water-soluble polymers and small molecules without compromising superhydrophobicity, providing methods for post-fabrication loading of water-soluble agents into protective non-wetting coatings that are difficult to achieve using other approaches.