The large blue-ringed octopus can change the size and color of the eponymous patterns on its skin for deception, camouflage and signaling, thanks to muscle contractions within seconds. Researchers at the University of California, Irvine were inspired by this natural wonder to develop a technology platform with similar capabilities for use in a variety of industries, including the military, medicine, robotics and sustainable energy.

According to its inventors, the new devices enabled by this innovation benefit from dynamically tunable fluorescence and spectroscopic properties, ease of fabrication, and the ability to scale to areas large enough to cover vehicles, billboards, and even buildings. Biological creation is the subject of a study published in the journal Science. Nature Communication.

Hapalochlaena lunulata is a species of octopus native to the Western Pacific and Indian Oceans. It uses its neurotoxin poison to stun its prey and can scare predators with its blue rings. It was these iridescent rings on the brown background of the creature’s skin that caught the UCI researchers’ attention.

“We were fascinated by the mechanisms underlying the blue-ringed octopus’ ability to rapidly switch skin tags between hidden and exposed states,” said senior co-author Alon Horodetskyi, UCI professor of chemical and biomolecular engineering.

“For this project, we sought to mimic the natural abilities of an octopus using devices made from unique materials we synthesized in our laboratory, and the result is an octopus-inspired trap and alarm system that is easy to fabricate and functions for a long operating time. It is continuous and can even regenerate itself when damaged.” .”

The innovation’s architecture calls for a thin film of wrinkled blue rings (similar to those in octopuses) surrounding brown rings, sandwiched between the top transparent proton-conducting electrode and an underlying acrylic membrane with another identical electrode underneath.

More technical creativity from researchers is at the molecular level as they explore the use of acenes, organic compounds composed of linearly fused benzene rings. According to Horodetskyi, the designer molecules the team used (nine rings fused linearly) help give the platform some extraordinary capabilities.

“For our devices, we conceptualized and designed a neacene-like molecule with a unique architecture,” said co-author Preeta Pratakshya, a recent Ph.D. in the UCI Department of Chemistry.

“Acenes are organic hydrocarbon molecules with many advantages, including ease of synthesis, tunable electronic properties, and controllable optical properties.”

He added: “Our noasene-like molecules are unique among acenes because they can survive years of storage in air and continuous exposure to bright light in the air over a day. No other elongated acene exhibits such combined long-term stability under such harsh conditions.”

According to Horodetsky, the type of molecules used to form the colored blue ring layer is what gives the devices the most advantageous properties, including tunable spectroscopic properties, facilitating simple benchtop fabrication, and environmental and atmospheric stability during illumination.

“Our co-author Sahar Sharifzadeh, a professor of electrical and computer engineering at Boston University, demonstrated that the properties of stimuli-responsive molecules can be computationally predicted, paving the way for the in silico design of other camouflage technologies,” Horodetskyi said. said. .

During laboratory tests, many of which were conducted at UCI’s California Telecommunications and Information Technology Institute, the team found that the biological devices could change their appearance more than 500 times with little or no degradation and self-heal without any degradation. user. intervene.

According to Horodetskyi, the invention has been shown to have the desired combination of capabilities in the ultraviolet, visible light and near-infrared portions of the electromagnetic spectrum. This will allow devices to hide other objects from detection or secretly send signals to observers.

“The photophysical stability and overall processability of our Neacene-like molecule (and possibly its variants) opens opportunities for future investigations of these compounds in the context of conventional optoelectronic systems such as light-emitting diodes and solar cells,” Horodetskyi said. he added. Source