Preventing water droplets from transitioning to ice is advantageous for numerous applications. It is demonstrated that the use of certain phase‐change materials, which are in liquid state under ambient conditions and have melting point higher than the freezing point of water, referred herein as phase‐switching liquids (PSLs), can impede condensation–frosting lasting up to 300 and 15 times longer in bulk and surface infused state, respectively, compared to conventional surfaces under identical environmental conditions. The freezing delay is primarily a consequence of the release of trapped latent heat due to condensation, but is also affected by the solidified PSL surface morphology and its miscibility in water. Regardless of surface chemistry, PSL‐infused textured surfaces exhibit low droplet adhesion when operated below the corresponding melting point of the solidified PSLs, engendering ice and frost repellency even on hydrophilic substrates. Additionally, solidified PSL surfaces display varying degrees of optical transparency, can repel a variety of liquids, and self‐heal upon physical damage.
The development of new technologies is key to the continued improvement of medicine, relying on comprehensive materials design strategies that can integrate advanced therapeutic and diagnostic functions with a variety of surface properties such as selective adhesion, dynamic responsiveness, and optical/mechanical tunability. Liquid‐infused surfaces have recently come to the forefront as a unique approach to surface coatings that can resist adhesion of a wide range of contaminants on medical devices. Furthermore, these surfaces are proving highly versatile in enabling the integration of established medical surface treatments alongside the antifouling capabilities, such as drug release or biomolecule organization. Here, the range of research being conducted on liquid‐infused surfaces for medical applications is presented, from an understanding of the basics behind the interactions of physiological fluids, microbes, and mammalian cells with liquid layers to current applications of these materials in point‐of‐care diagnostics, medical tubing, instruments, implants, and tissue engineering. Throughout this exploration, the design parameters of liquid‐infused surfaces and how they can be adapted and tuned to particular applications are discussed, while identifying how the range of controllable factors offered by liquid‐infused surfaces can be used to enable completely new and dynamic approaches to materials and devices for human health.
more » « less- NSF-PAR ID:
- 10073572
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 30
- Issue:
- 50
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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