(From left) Daniel Preston, Kai Ye, Yizhi Jane Tao, and Marquise Bell (Image: Gustavo Raskosky/Rice University)

A new material developed by Rice University engineers that packs deadly heat for viruses on its outer surface while staying cool on the reverse side could transform the way we make and use personal protective equipment (PPE), cutting down the pollution and carbon footprint associated with current materials and practices.

The composite, textile-based material uses Joule heating to decontaminate its surface of coronaviruses like SARS-CoV-2 in under 5 seconds, effectively killing at least 99.9 percent of viruses. Wearable items made from the material can handle hundreds of uses with the potential for a single pair of gloves to prevent nearly 20 pounds of waste that would have resulted from discarded single-use nitrile gloves.

“The surge in magnitude of PPE waste and problems caused by supply chain shortages during the pandemic made us realize the need for reusable PPE,” said Lead Author Marquise Bell. “This work paves the way for a systemic shift away from single-use disposable PPE.

“The best part is you don’t even need to take off the gloves or other protective garments to clean them. This material allows you to decontaminate in seconds, so you can get back to the task at hand.”

Using electrical current, the material rapidly heats up its outer surface to temperatures above 100 °C (212 °F), while remaining close to normal body temperature on the reverse side near the user’s skin where it reaches a maximum of about 36 °C (97 °F).

A glove made of a material designed at Rice University that kills coronaviruses with heat without burning users’ skin. (Image: Gustavo Raskosky/Rice University)

“The device has to get hot enough to effectively kill viruses, but not so hot that it causes burns or discomfort for the user,” Bell said. “We included safety mechanisms to make sure the latter doesn’t happen.”

“Our lab has looked a lot at the thermal inactivation of viruses,” said co-author Dan Preston. “We started during the pandemic with support from a National Science Foundation grant, trying to understand the mechanism by which these viruses are inactivated and how it's accelerated at higher temperatures.”

Here is an exclusive Tech Briefs interview — edited for length and clarity — with Bell and Preston.

Tech Briefs: I’m sure there were too many to count, but what was the biggest technical challenge you faced while developing this material?

Bell: The biggest technical challenge we encountered was accurately relating the thermal performance of the material to its intrinsic properties and geometry. We already had a sense for how the temperature of the material relates to virus inactivation, but it took some time to better understand how the geometry of the material, and its inherent thermal properties, relate to the temperature produced on its surface.

Tech Briefs: Can you explain in simple terms how it works?

Preston: Our material converts electricity to heat, which raises the temperature of the surface of the material and effectively renders viral contaminants inactive. We are able to do so without the user having to take garments made from the material off due to the incorporation of a thermally insulating layer that mitigates the flow of heat to the skin.

Tech Briefs: Bell, you’re quoted as saying, “We included safety mechanisms…” What kind of safety mechanisms were included?

Bell: We included a wearable controller in the portable demonstration that limits the duration of the electrical heating applied to the material to a safe, proven dose. Similarly, in another demonstration without a battery, the user wears a garment containing our material and contacts a wall-mounted panel via a magnetic connection.

This system first measures the electrical resistance of the material and then calculates the time necessary for the duration of electrical heating for thermal decontamination under a constant voltage, allowing safe operation even if the electrical resistance of the material were to change over the course of use.

Tech Briefs: How soon could we see this material commercialized?

Bell: We are excited to show how our material can help pave the way toward reusable PPE, especially in a comfortable textile-based architecture. We do not have a current timeline for the commercialization of this material, but we have begun discussing ideas about how to apply this material to other garments besides gloves to help bring this material, and others like it, into the consumer space.

Tech Briefs: What are your next steps?

Preston: We plan to build upon the framework we developed in this study, which relates the electrical properties of the material to its subsequent thermal performance and the resulting reaction kinetics of virus inactivation, to other commonly touched surfaces and materials, like doorknobs or handrails. We are also translating our platform for electrical heating in textiles to thermoregulatory garments, which Marquise investigates through his NASA fellowship (NSTGRO 2021) for spacesuit applications.

Tech Briefs: Do you have any advice for engineers/researchers aiming to bring their ideas to fruition?

Bell: I would say that you just have to try it out. Sometimes it’s hard to bring an idea to life because there is not always a clear starting point. I think it’s then when you just have to go for it because you have to start somewhere. Take the knowledge you know and apply it along the way. You’ll learn more about your material, device, or system as you progress.