Background
Ultraviolet treatment creates water-attracting tracks on a water-repellent silicon-nanowire surface, guiding droplets along chosen paths. Resetting the tracks requires recoating and another UV treatment.
What the study found
Selective ultraviolet exposure breaks down a DTS coating on silicon nanowires, leaving water-wetting tracks that guide droplets.
The route relies on a difference in wettability between the track and its surroundings. Changing the route requires recoating and another UV treatment.
Questions and limits
The study does not establish switching in both directions with UV alone or equivalent transport of biological fluids.
How to compare the results
Compare droplet volume and surface tension, surface tilt, track width, and contact-angle hysteresis.
Related reading
How to Make Water Run Uphill
DOI: 10.1126/science.256.5063.1539 ↗
The related paper’s abstract describes droplet motion driven by a surface-energy gradient. It offers a comparison with the patterned routes used here.
Account for tilt, contact-angle hysteresis and droplet size when comparing motion.
Abstract-based introductionSources used in this summary
This account draws on the abstract and conclusion in the public author-hosted published article. It does not represent a complete review of the article, supplements or raw data. The comparison conditions are suggestions for reading studies together.