An electrochemical process developed at Georgia Tech could offer new protection against bacterial infections without contributing to growing antibiotic resistance.
The approach capitalizes on the natural antibacterial properties of copper and creates incredibly small needle-like structures on the surface of stainless steel to kill harmful bacteria like E. coli and Staphylococcus. It’s convenient and inexpensive, and it could reduce the need for chemicals and antibiotics in hospitals, kitchens, and other settings where surface contamination can lead to serious illness.
It also could save lives: A global study of drug-resistant infections found they directly killed 1.27 million people in 2019 and contributed to nearly 5 million other deaths—making these infections one of the leading causes of death for every age group.
Researchers described the copper-stainless steel and its effectiveness May 20 in the journal Small.
“Killing Gram-positive bacteria without chemicals is comparatively easy but tackling Gram-negative bacteria poses a significant challenge, due to their thick, multilayered cell membrane. And if these bacteria persist on surfaces, they can grow rapidly,” said Anuja Tripathi, the study’s lead author and a postdoctoral scholar in the School of Chemical and Biomolecular Engineering. “I aimed to develop an antibiotic-free bactericidal surface effective against Gram-negative and Gram-positive bacteria.”
Tripathi and her colleagues—William R. McLain Professor Julie Champion and former Ph.D. students Jaeyoung Park and Thomas Pho—produced a one-two punch that overcomes those challenges and doesn’t help bacteria develop resistance to drugs.
The team first developed an electrochemical method to etch the surface of stainless steel, creating nano-sized needle-like structures on the surface that can puncture bacteria’s cell membranes. Then, with a second electrochemical process, the researchers deposited copper ions on the steel’s surface.
Copper interacts with the cell membranes and ultimately compromises them.
“The nanotextured stainless steel can kill both Gram-negative and Gram-positive bacteria, but we wanted to enhance the antibacterial activity for surfaces that can be highly contaminated,” Tripathi said. “The copper coating on the nanotextured stainless steel gave us very high antibacterial activity.”
and c,e) nanotextured stainless steel etched for 30 s at 8 V. Credit: Small (2024). DOI: 10.1002/smll.202311546
Despite copper’s known antibacterial properties, it’s not widely used to fight surface contamination because it’s expensive. Tripathi’s approach deposits only a thin layer of copper ions on the stainless steel, so it’s cost-effective without compromising the material’s antibacterial activity.
Together, the dual attacks resulted in 97% reduction of Gram-negative E. coli and 99% reduction in Gram-positive Staphylococcus epidermis bacteria in the group’s study.
Tripathi said the stainless steel could be used for common tools in medical settings that are easily fouled, such as scissors or tweezers. It could be used for door handles, stair railings, and perhaps even sinks—places where stainless steel is often the material of choice and surface bacteria are common, especially in hospitals or other shared settings.
The process she and her colleagues developed also could be useful in food service. Tripathi said the approach could be fairly easily incorporated into existing industrial processes, where different electrochemical coating methods already are used for stainless steel food storage containers.
Tripathi said future work will investigate if the copper-coated, nanotextured stainless steel is effective against other kinds of cells harmful to human health. She’s also interested in exploring whether the steel could be used for medical implants to help ward off infections.
Since it proved effective against troublesome E. coli, she’s hopeful.
“Reflecting on a recent E. coli outbreak in grocery stores in Calgary, Canada, I was particularly driven in my research, recognizing the urgent relevance and significance of combating such resilient bacteria on surfaces,” Tripathi said. “They can be difficult to eliminate. So, if we can effectively eliminate E. coli, we stand a good chance of eradicating many bacteria on surfaces.”
More information: Anuja Tripathi et al, Dual Antibacterial Properties of Copper‐Coated Nanotextured Stainless Steel, Small (2024). DOI: 10.1002/smll.202311546
Journal information: Small
Provided by Georgia Institute of Technology

News
Repurposed drugs could calm the immune system’s response to nanomedicine
An international study led by researchers at the University of Colorado Anschutz Medical Campus has identified a promising strategy to enhance the safety of nanomedicines, advanced therapies often used in cancer and vaccine treatments, [...]
Nano-Enhanced Hydrogel Strategies for Cartilage Repair
A recent article in Engineering describes the development of a protein-based nanocomposite hydrogel designed to deliver two therapeutic agents—dexamethasone (Dex) and kartogenin (KGN)—to support cartilage repair. The hydrogel is engineered to modulate immune responses and promote [...]
New Cancer Drug Blocks Tumors Without Debilitating Side Effects
A new drug targets RAS-PI3Kα pathways without harmful side effects. It was developed using high-performance computing and AI. A new cancer drug candidate, developed through a collaboration between Lawrence Livermore National Laboratory (LLNL), BridgeBio Oncology [...]
Scientists Are Pretty Close to Replicating the First Thing That Ever Lived
For 400 million years, a leading hypothesis claims, Earth was an “RNA World,” meaning that life must’ve first replicated from RNA before the arrival of proteins and DNA. Unfortunately, scientists have failed to find [...]
Why ‘Peniaphobia’ Is Exploding Among Young People (And Why We Should Be Concerned)
An insidious illness is taking hold among a growing proportion of young people. Little known to the general public, peniaphobia—the fear of becoming poor—is gaining ground among teens and young adults. Discover the causes [...]
Team finds flawed data in recent study relevant to coronavirus antiviral development
The COVID pandemic illustrated how urgently we need antiviral medications capable of treating coronavirus infections. To aid this effort, researchers quickly homed in on part of SARS-CoV-2's molecular structure known as the NiRAN domain—an [...]
Drug-Coated Neural Implants Reduce Immune Rejection
Summary: A new study shows that coating neural prosthetic implants with the anti-inflammatory drug dexamethasone helps reduce the body’s immune response and scar tissue formation. This strategy enhances the long-term performance and stability of electrodes [...]
Scientists discover cancer-fighting bacteria that ‘soak up’ forever chemicals in the body
A family of healthy bacteria may help 'soak up' toxic forever chemicals in the body, warding off their cancerous effects. Forever chemicals, also known as PFAS (per- and polyfluoroalkyl substances), are toxic chemicals that [...]
Johns Hopkins Researchers Uncover a New Way To Kill Cancer Cells
A new study reveals that blocking ribosomal RNA production rewires cancer cell behavior and could help treat genetically unstable tumors. Researchers at the Johns Hopkins Kimmel Cancer Center and the Department of Radiation Oncology and Molecular [...]
AI matches doctors in mapping lung tumors for radiation therapy
In radiation therapy, precision can save lives. Oncologists must carefully map the size and location of a tumor before delivering high-dose radiation to destroy cancer cells while sparing healthy tissue. But this process, called [...]
Scientists Finally “See” Key Protein That Controls Inflammation
Researchers used advanced microscopy to uncover important protein structures. For the first time, two important protein structures in the human body are being visualized, thanks in part to cutting-edge technology at the University of [...]
AI tool detects 9 types of dementia from a single brain scan
Mayo Clinic researchers have developed a new artificial intelligence (AI) tool that helps clinicians identify brain activity patterns linked to nine types of dementia, including Alzheimer's disease, using a single, widely available scan—a transformative [...]
Is plastic packaging putting more than just food on your plate?
New research reveals that common food packaging and utensils can shed microscopic plastics into our food, prompting urgent calls for stricter testing and updated regulations to protect public health. Beyond microplastics: The analysis intentionally [...]
Aging Spreads Through the Bloodstream
Summary: New research reveals that aging isn’t just a local cellular process—it can spread throughout the body via the bloodstream. A redox-sensitive protein called ReHMGB1, secreted by senescent cells, was found to trigger aging features [...]
AI and nanomedicine find rare biomarkers for prostrate cancer and atherosclerosis
Imagine a stadium packed with 75,000 fans, all wearing green and white jerseys—except one person in a solid green shirt. Finding that person would be tough. That's how hard it is for scientists to [...]
Are Pesticides Breeding the Next Pandemic? Experts Warn of Fungal Superbugs
Fungicides used in agriculture have been linked to an increase in resistance to antifungal drugs in both humans and animals. Fungal infections are on the rise, and two UC Davis infectious disease experts, Dr. George Thompson [...]