Reviewed by Frances BriggsJul 30 2025
A new graphene-based coating developed in Manchester offers a more precise way to release silver ions, promising longer-lasting antibacterial protection without harming healthy tissue.
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Researchers at the National Graphene Institute have created an antibacterial membrane that could make surfaces cleaner and safer in medical, consumer, and industrial settings. The coating, designed to release silver ions gradually rather than all at once, was developed in collaboration with medical technology firm Smith & Nephew. The findings have been published in the journal Small.
Silver has long been used to fight infection. In modern medicine, it's a common ingredient in wound dressings thanks to its ability to release ions that disrupt bacterial cells. However, present techniques still present some issues: silver can be released too quickly or unevenly, damaging adjacent healthy tissue and resulting in ineffective or inconsistent antibacterial protection.
The team at the University of Manchester aimed to solve this by designing a graphene oxide membrane with tightly controlled nanoscale channels. They act like molecular sieves, regulating how much silver is released and when. The result is a more stable and predictable antibacterial effect.
Professor Rahul Nair, who led the research, said the work represents a paradigm shift in antimicrobial coating technology.
By harnessing the potential of graphene oxide membranes, we've unlocked a method for controlled silver ion release, paving the way for sustained antimicrobial efficacy in various applications.
Rahul Nair, Professor, The University of Manchester
To test how the coating would behave in real-life conditions, the researchers created a new laboratory model to simulate the human body more accurately. They used fetal bovine serum, a fluid rich in proteins similar to those found in blood, to mimic how the coating might perform inside wounds or on implants.
Dr Swathi Suran, the study's first author and a researcher at imec, said this gave the team a clearer picture of how the coating might work in practice.
This approach allows us to deliver just the right amount of silver for extended protection. It has potential in many areas, including wound care dressings and antimicrobial coatings for implants, and could bring long-term benefits for both patients and healthcare providers.
Dr. Swathi Suran, Study First Author and Researcher, imec
The researchers are now exploring the wider use of these membranes and how the coating can be incorporated into several everyday and medical products to reduce the threat of bacterial resistance.
Journal Reference:
Suran, S. et al. (2025). Tunable Release of Ions from Graphene Oxide Laminates for Sustained Antibacterial Activity in a Biomimetic Environment (Small 28/2025). doi.org/10.1002/smll.202570220.