The Indian Institute of Technology (IIT) Madras has patented a new antibacterial surface designed to eliminate harmful bacteria without relying on antibiotics, disinfectants, radiation or other antimicrobial chemicals. The technology is aimed at addressing antimicrobial resistance (AMR), a growing health challenge in which bacteria become resistant to medicines used to treat infections. Instead of attacking bacteria chemically, the IIT Madras approach uses the physical structure of the surface itself. The researchers created extremely small, densely packed structures on a flexible, implant grade silicone surface. These structures, described as “nanograss,” create intense mechanical stress when bacteria come into contact with them. That pressure can rupture the bacterial cell wall and ultimately destroy the cell.

Since the mechanism is physical rather than chemical, the surface does not need to release an antibacterial drug or chemical agent to work. The surface was produced using a customised low pressure plasma technique called Reactive Ion Etching (RIE). Researchers also found that the process creates a stiff surface layer that helps transfer mechanical forces more effectively to bacterial cells. The team tested the technology against three different bacterial species, covering both Gram positive and Gram negative bacteria. The engineered surfaces showed strong bactericidal activity and achieved more than 68% inhibition of biofilm formation across the tested strains. Another important finding was its compatibility with mammalian cells. Tests using fibroblast cells recorded viability of up to 91%, suggesting that the surface could potentially be developed for applications where contact with human tissue is involved. The technology could eventually have uses in several areas where bacterial contamination is a concern. Researchers have identified possible applications including medical implants, urinary catheters, wound care products, hospital equipment and pharmaceutical packaging.

It could also potentially be adapted for frequently touched public surfaces, such as transport handrails and other public infrastructure. The research follows a biomimetic approach, drawing inspiration from naturally occurring antibacterial nanostructures such as those found on dragonfly wings. Researchers are exploring how similar physical mechanisms can be recreated through engineered surfaces. By avoiding antibacterial chemicals, the technology could also reduce concerns around chemical leaching and potentially lower the pressure that drives bacteria to develop resistance. The research has been published in ACS Applied Biomaterials. If successfully scaled and further validated, the IIT Madras innovation could offer a different way of protecting surfaces from harmful bacteria by designing the surface to destroy microbes mechanically rather than relying on conventional chemical based antibacterial treatments.