Scientists Found A Way To Kill Viruses Without Chemicals: Tiny Plastic Spikes

This Plastic Film Is Covered in Invisible Spikes That Tear Viruses Apart on Contact

During the COVID-19 pandemic, people wiped down groceries, sanitized doorknobs, and sprayed disinfectant on just about everything. While all of that was done out of necessity at the time, chemical-based solutions have real drawbacks: they wear off, they can be toxic, and overuse might help germs develop resistance. Now an international team of researchers has taken a radically different approach, engineering a flexible plastic film covered in microscopic spikes so tightly packed they physically rupture viruses on contact.

Certain insect wings and plant leaves have tiny surface structures that kill bacteria without any chemical help. Scientists have studied these bacteria-killing surfaces for years, but whether the same trick could work on viruses, far smaller than bacteria, remained an open question.

Published in Advanced Science, the research shows that acrylic films with tightly spaced tiny pillars can slash the infectivity of a common respiratory virus in just one hour under controlled laboratory conditions. No chemical disinfectants, no antiviral agents, no coatings that deplete over time. The virus-killing power comes entirely from the physical shape of the surface itself.

How These Virus-Killing Plastic Spikes Work

To understand how these surfaces work, consider the scale. The pillars on the most effective films are spaced just 60 billionths of a meter apart, roughly a thousand times narrower than a human hair. When a virus lands on this forest of tiny spikes, its outer shell stretches across multiple pillar tips. The damage happens not where the shell touches the pillars but in the regions between them, where the shell is suspended and being stretched. That stretching generates enough force to rupture the shell and destroy the virus’s ability to infect cells.

Researchers at institutions including RMIT University in Australia, the University of Melbourne, Universitat Rovira i Virgili in Spain, and Tokyo Metropolitan University made these films by stamping tiny patterns into a light-cured acrylic resin using aluminum molds with precisely arranged holes. The process is already used in industrial manufacturing, suggesting a plausible path to broader production.

The team tested their films against human parainfluenza virus type 3, a respiratory germ that causes serious illness, especially in children, the elderly, and people with weakened immune systems. No approved vaccines or antiviral drugs currently exist for it, which makes surface-based prevention especially relevant.

Why Spike Spacing on These Virus-Killing Surfaces Matters More Than Height

One of the study’s most notable findings is that the distance between the pillars matters far more than how tall they are. Films with that same tight 60-nanometer spacing consistently cut viral infectivity regardless of pillar height. Densely packed arrays reduced infectivity by an average of roughly fivefold, with the best-performing surfaces hitting about a 16-fold reduction, or up to roughly 94%.

Widening the spacing to 100 billionths of a meter dropped antiviral performance noticeably and made height matter more. At 200 billionths of a meter apart, the surfaces showed no antiviral activity at all. At that spacing, a virus typically touches only one pillar at a time, which generates nowhere near enough force to rupture the outer shell.

Statistical analysis confirmed that pillar spacing was the dominant factor in determining how much virus survived on the surface, with height playing a secondary, spacing-dependent role.

What the Damage Looks Like Up Close

Researchers also watched what happened to individual virus particles using powerful electron microscopes. Images showed viral particles on the densely packed surfaces appearing deflated and misshapen. Some pillars bent or flexed on contact, and in some cases the tiny spikes clustered around viral particles, tightening their grip. Scientists who then sliced through the surface to get a side-on view could see the pillars actually embedded inside the virus particles, their round shapes collapsed and broken.

When researchers analyzed the genetic material recovered from these surfaces, they found it remained intact. That’s a telling clue: viral RNA surviving while infectivity crashes confirms the surfaces aren’t relying on chemical reactions. It’s the structural damage to the outer shell that stops the virus from infecting cells.

Computer simulations backed this up, showing stress concentrating in the suspended regions between pillar tips and exceeding the estimated threshold for rupture. An optimal ratio of pillar spacing to virus diameter emerged from the modeling: surfaces where that ratio fell between 0.2 and 0.5 produced the strongest virus-killing effects, a potential design formula for targeting different virus sizes. Hitting that mark across the full range of respiratory viruses, which vary widely in diameter, remains a challenge.

A Practical Path From Lab to Everyday Surfaces

Beyond the science, what makes this work stand out is the material. Acrylic is already everywhere: protective screens, consumer electronics, automotive interiors, medical devices, food packaging. It’s transparent, shatter-resistant, lightweight, and nontoxic. The manufacturing method is compatible with roll-to-roll production, meaning structured films could be made in large continuous sheets, and researchers noted they’ve already built a roll-type mold enabling continuous stamping onto flexible surfaces.

In supplementary testing, the films also showed bacteria-killing effects against two well-known bacterial strains. That said, the study tested only one virus type, so the full scope of effectiveness across other pathogens remains to be determined.

For a world still grappling with respiratory virus spread in hospitals, schools, and public transit, a durable, mass-producible antiviral surface free of chemical disinfectants would be a meaningful step forward. Acrylic’s performance here also outpaced earlier work on spike-covered silicon, which achieved a smaller viral reduction over a longer period. Real-world performance under variable conditions has not yet been evaluated, but the study doesn’t just prove the concept works. It delivers the geometric blueprint for making it work as effectively as possible.

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