Bioinspired platform with reversibly switchable wettability for transfer and storage of droplets

Inspired by rose petals, a novel and facile method to prepare smart surface with controllable wettability for transfer and patterned storage of droplets was presented. The smart surface was obtained by alternately depositing PDDA and PSS on a copper substrate with mastoid structure prepared by laser processing. It was found that the wettability of the as-prepared copper surface can switch reversibly between superhydrophobic and superhydrophilic state. In addition, the as-prepared surface had excellent physical and chemical stability. In theory, our droplet storage platform can be processed into any size and shape to achieve different requirements for droplet storage. This study provides a simple route to fabricate bioinspired rewritable platform with reversibly switchable wettability for lossless transfer and patterned storage of droplets. It may be helpful for the development of the devices for droplet transfer and functionalized droplet storage. This method can also be applied to biodetection, microfluidic switching, and chemical microreaction.