Low-cost technology could be employed in hand-held devices and ventilation systems

Irvine, Calif., May 19, 2020 – A new weapon in the arsenal against the coronavirus may be sitting in your home entertainment console. A team led by physicist Chris Barty of the University of California, Irvine is researching the use of diodes from Blu-ray digital video disc devices as deep-ultraviolet laser photon sources to rapidly disinfect surfaces and the indoor air that swirls around us.

Barty, UCI Distinguished Professor of physics & astronomy, said that such UV light sterilizers would be cheap compared to current medical- and scientific-grade systems and that it’d be possible to deploy them almost anywhere.

“If these sources are successful, I think you could build them into a mask and clean the air that’s coming in and out of you,” he said. “Or you could set these things up in the air circulation ducts of major buildings, and the airflow that goes through could be sterilized.”

They could also function in hand-held wand devices, Barty said, or as a “light curtain” through which people walk as they enter a room, exposing them to UV-C radiation. He noted that at this wavelength – between 200 and 260 nanometers – UV radiation will destroy viruses and other pathogens but poses minimal risk to humans.

“There is evidence to suggest that the UV-C band is actually not an issue for us, especially at the shorter wavelengths, because it gets absorbed by dead skin cells or by a teardrop on your eye,” said Barty, head of UCI’s Convergent Optical Sciences Initiative.

“Hospitals use UV-emitting robots that are about the size of a dorm room refrigerator. They just wheel them in and plug them into the wall to sterilize the place, but everybody has to leave because in addition to UV-C, they make a lot of UV-A and UV-B, which can cause harm to humans.”

The cost of these roaming hospital sterilizers – that are based on high-current mercury discharge lamps – is too high for deployment at the scale that may be needed to combat the coronavirus, present everywhere from cruise ships to meatpacking plants. Barty said that Blu-ray diode lasers offer a potential path to a compact, economical solution, since the technology is ubiquitous and priced in the range of tens of dollars per unit.

His team is developing a way to halve the wavelength of photons emitted by Blu-ray diodes – which is around 405 nanometers – to the germicidal UV-C band.

“This is really more of an applied physics versus a pure physics view of the world,” he said. “The issue is not whether you can make UV-C light. It’s whether you can fundamentally reduce the dollar-per-watt output of a device to a place that it becomes compelling to use UV-C light.”

According to Barty, Blu-ray sterilizers could be made in the “same kind of quantities as you can make other telecommunications components, so you could really change the game.”

Looking at the current landscape, in which there’s an all-hands-on-deck effort to develop vaccines to prevent COVID-19 infections and drugs to treat people sick with the virus, Barty observed: “I would prefer that we just destroy it.”

This project and many other currently active UCI-based initiatives to confront the coronavirus are being tracked at https://oc-covid19.org.

Read the full UCI press release.

“I had an appreciation for how complex and sophisticated these devices are,” Radulescu said. “We were immediately aware that we would not be able to recreate or replace them.”

So, Virgin Orbit decided to design its own.

Radulescu notes that there is some overlap in the engineering of ventilators and rockets. The same math and physics apply to pressure — whether it’s the pressure of a rocket fuel combustion chamber or the pressure ventilators use to push oxygen into a patient’s lungs. But the scale is radically different: Rocket engineers think about pressure in terms of pounds per square inch, a unit 70 times larger than the one used in the medica equipment world.

“In some ways, the level of testing and verification we have to meet for aerospace are much more stringent than what I had seen in [the medical device field],” Radulescu added. After all, “our electronics have to work in the vacuum of space, being bombarded by solar and cosmic radiation at extreme temperature ranges.”

A call to action

As the coronavirus outbreak spread into the United States, Dr. Brian Wong, a plastic surgeon at the University of California, Irvine Medical Center, wanted to know what doctors on the front lines could do if they ran out of ventilators. In March, Wong organized daily conference calls on Zoom to brainstorm ideas with a couple of his colleagues, and they adopted the name Bridge Ventilator Consortium. Soon, medical professionals from all over the country began dialing in.

The next morning, they purchased a windshield wiper motor from Autozone and met up with two more of their colleagues for a marathon engineering session. They designed the machine to use as few components as possible and relied on parts that Virgin Orbit could easily find in large numbers.

“If the goal is to allow the clinician to set this machine up and walk away, we should add different alarms and warnings,” Radulescu said. “One thing I’d seen on other ventilators is, if the power disconnects, the [device] will actually [make] an extremely loud and audible signal that says, ‘Hey, you’ve lost power here!'”

The team assembled its first prototype within a day, and less than a week later they built a second and third version and sent the design to US regulators for approval, Radulescu said.

“I was amazed.” Dr. Govind Rajan, an anesthesiologist at UCI, said. “They took all these ideas, synthesized them and they put it together very fast — which is what is critical right now.”

From prototype to production

Some Virgin Orbit employees are still focused on rockets. A skeleton staff continues to work toward the company’s first orbital launch attempt in the coming weeks. But the startup estimates it can also churn out 100 bridge ventilators within a week, double that rate a week later, and continue scaling up from there. Virgin Orbit says the devices could be manufactured on assembly lines set up right alongside the rocket bodies and engines that litter its 180,000 square-foot factory.

The company said the vast majority of its employees are working from home, and those who must be on site at the factory will maintain proper social distancing whenever possible.

Radulescu, who said the ventilator team has been careful to keep their distance while in the same room together, said they are still working out how to avoid potential kinks in its supply chain, particularly when it comes to the Ambu bags.

“We want to make sure we’re not in a position where we’re competing with hospitals,” he said. His team is planning to deliver its first batch of ventilators fully assembled, and then allowing hospitals to buy the Ambu bags themselves. The machine is designed to allow doctors to install the bags into the bridge ventilator machine when needed.

But before mass production can start, Virgin Orbit needs the green light from the Food and Drug Administration.

The agency said last month that it wanted to do everything possible to expedite approvals for such devices, and Will Pomerantz, Virgin Orbit’s vice president of special projects, said regulators are helping the startup navigate the application process.

The agency has to walk a fine line — balancing the urgent need to get lifesaving devices in the hands of doctors, and ensuring stopgap solutions are still safe.

Meanwhile, doctors all over the world fear shortages would force them to choose which patients to save.

“There is no ideal solution,” Wong said. He added that bridge ventilators are among dozens of proposed alternatives to traditional ventilators — and nobody yet knows how effective any given approach will be.

It’s not yet clear if any of those patients have since recovered from the virus.

For all their efforts, the Virgin Orbit engineers say they hope doctors will never be forced to use their machines. But they’re still working tirelessly, Radulescu said, adding that looming medical supply shortages felt like “a call to action.”

Read the CNN Business article.