Precise control of a biological droplet's adhesive force on a liquid-repellent surface for smart antifouling systems is critical and fundamental to scientific research and industrial applications. Although slippery surfaces with stimuli-responsive wetting behaviors have been reported, challenge still remains in designing responsive biological droplets to achieve controllable adhesion and antifouling property. Here, we developed a thermoresponsive biological droplet adhesion system to precisely control its adhesion on the lubricant-infused slippery surface. Single-stranded DNA (ssDNA) in the biological droplet displays molecular configuration reversible deformation under external thermal stimuli. This property ascribes to the changing amount of exposed hydrophobic moieties of ssDNA, which strongly affects the interfacial hydrophobic interaction with the lubricant. This work may improve the understanding of the principles underlying liquid-lubricant interfacial adhesion, open up opportunities for a new class of antifouling systems, and provide a promising system for controllable manipulation of liquids' motion in biochips and microreactor devices.
Keywords: controllable droplet motion; hydrophobic interaction; interfacial adhesion; slippery surface; temperature-responsive.