Although the creation of human plastrons would have many possible uses in human underwater exploration, size restraints and the high metabolic needs of humans would make the use of a human plastron respiration apparatus impossible (Flynn and Bush 2008). However, that does not mean that biomimicry of plastrons does not have numerous technological implications.

It is first important to point out that it is indeed to create an artificial plastron surface. In fact, Shirtcliffe et al demonstrated in 2006 that the highly water-repellant foam that they created acted just as an arthropod's plastron by extracting oxygen from water. Water-repellant surfaces already play a large role for many technological and industrial purposes, including reducing frictional drag in water, creating stain-resistant textiles, developing self-cleaning windows, and many others common applications (Shirtcliffe et al 2006). Other possible technological applications of plastron surfaces include other aquatic possibilities, including unwettable swimwear or drag reduction for the hulls of boats and ships. Such drag reduction would be possible because without the superhydrophobic surface there exists a solid-water contact, but when a water-repellant surface is present, it replaces the solid-water interaction with air-water interactions (Balmert et al 2011).

However, another aspect of plastrons, besides their superhydrophobic properties, is their ability to absorb oxygen from the aerated water surrounding it. Thus, in order for a surface to truly mimic a plastron surface, it must have the ability to absorb oxygen from the water surrounding it. Investigations in this area began when it was observed that the silvery surface reflection that is found on arthropod plastrons was also observed on a man-made water-repellant surface.

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The silvery nature of the plastron surface referred to by Shirtcliffe et al (Credit: Norbert Schuller Baupi / Wikimedia Commons)

This qualitative similarity between artificial water-repellant surfaces and the natural plastron surface led to investigations to discover if man-made surfaces could mimic the actions of plastrons.

The investigation was carried out by creating an artificial, superhydrophobic foam material (methyltriethoxysilane and a phase separation process). A cylinder of this material was then hollowed out to create a cavity comparable to the plastron bubble. The foam was then placed in an aerated water bath, in which the oxygen levels were monitored. The results demonstrated that the oxygen concentration within the foam mimicked the oxygen concentration of the water as it changed. This demonstrates that the superhydrophobic material does in fact have the ability to act as a plastron (Shirtcliffe et al 2006).

One possible technological implication of this investigation and the fact that this artificial superhydrophobic surface allows the diffusion of oxygen could be in relation to fuel cells.

A simplified model of a fuel cell. An input of oxygen is required. Diagram synthesized using information from "Types of Fuel Cells" by the U.S. Department of Energy

Because this superhydrophobic foam has the ability to absorb oxygen from its surrounding water (just as an insect or spider plastron does), this indicates that fuel cells contained in the artificial material could be used to run miniature machines underwater without having to store oxygen supplies (Shirtcliffe et al 2006). However, this technology would be limited to miniature machines only, due to the size constraints explained earlier. One other possible constraint to this technological application could include bio-fouling by algae, barnacles, etc. (Flynn and Bush 2008).