With personal protective equipment, the best defense is going on offense

A DARPA-backed antimicrobial technology that aims to lighten the burden of protective gear is moving from the lab into limited clinical use inside the U.S. military health system, with early deployments underway at Walter Reed National Military Medical Center, according to the Defense Advanced Research Projects Agency.

The system, developed by Seattle-based startup Singletto under DARPA’s Personalized Protective Biosystem (PPB) program, embeds a long-used medical dye, methylene blue, into everyday materials. When exposed to light, the dye produces reactive oxygen species—specifically singlet oxygen—that can inactivate a broad range of viruses and bacteria. DARPA says the company has integrated the approach, branded Oxafence Active Protection, into lightweight, less-encumbering gear, including face masks now being evaluated in select military medical settings.

The effort targets a long-standing tradeoff in personal protective equipment: traditional barrier-based gear can be effective but heavy, hot, and restrictive, potentially undermining operational performance and compliance. PPB set out to flip that equation by developing protective systems that actively neutralize biological threats rather than merely blocking them.

Moving a material that claims to kill or disable pathogens into real-world use is as much a regulatory and market exercise as it is a scientific one. Antimicrobial products can fall under a patchwork of federal oversight, including the Food and Drug Administration for certain medical devices and the Environmental Protection Agency for materials that make pesticidal claims, depending on intended use and labeling. Manufacturing scale, durability under real-world conditions, and user training also factor heavily into adoption.

Those complexities are the focus of a parallel DARPA program, the Embedded Entrepreneur Initiative (EEI), run by the agency’s Commercial Strategy Office. EEI supplies commercialization support to select DARPA performers to help them navigate defense and healthcare markets, align products with urgent operational needs, and engage early evaluators.

“PPB helped validate that there was real potential for this technology, and EEI helped us understand where to take it next, and how,” said John Bjornson, co-founder and CEO of Singletto. “For a startup, navigating federal and healthcare pathways can be complicated. EEI is helping us build awareness, focus on the right opportunities, and connect with people who could evaluate where Oxafence might solve problems they were already trying to address.”

At Walter Reed, DARPA says the Oxafence-enabled masks are being introduced to clinical stakeholders interested in whether an active pathogen-inactivation feature matters in day-to-day practice. Beyond lab performance, the evaluation is intended to probe practical questions that often determine whether new PPE sticks: Does perceived active protection raise user confidence? Does it improve acceptance and adherence where consistent mask use still matters? And does the technology fit into existing workflows without adding burden?

The company is also looking to expand the technology beyond masks into areas such as advanced wound care, protective textiles, bioaerosol filtration, and other next-generation protective systems—each with its own technical validation and regulatory hurdles. Methylene blue–based photodynamic inactivation has a deep scientific literature behind it, but performance can depend on variables like light intensity, exposure time, and material design. Translating that into durable, washable, or field-ready products that work under varied lighting and operational conditions will be a key test.

Singletto’s transition from a high-risk research performer to an early-stage supplier illustrates how DARPA is trying to close the persistent gap between breakthrough development and widespread adoption. The agency has long been known for seeding transformative technologies; in recent years it has added structured commercialization efforts to ensure promising capabilities don’t stall after programs end.

“DARPA’s mission is to create and prevent technological surprise for national security, something we cannot achieve if the breakthrough capabilities we develop fail to thrive after their programs conclude,” said Wil Corvey, senior advisor, DARPA’s Commercial Strategy Office. “Singletto’s journey is a prime example of how EEI support can help a small business turn DARPA-funded research into a capability with commercial traction.”

Neither DARPA nor Singletto disclosed timelines for broader deployment or regulatory milestones. For now, the focus appears to be on targeted evaluations in settings where active antimicrobial features could deliver near-term operational benefits and on mapping the most viable paths through defense and healthcare procurement channels.

If those efforts succeed, Oxafence-enabled products could offer a new class of self-disinfecting gear designed to reduce heat and mobility penalties while providing an additional layer of protection against evolving biological threats—echoing PPB’s original aim to make protection lighter, smarter, and more resilient.