Birmingham University reveals antimicrobial discovery

Researchers show silver retains antimicrobial activity for longer when it is infused into bioactive glass

University of Birmingham researchers have shown that silver retains antimicrobial activity for longer when it is infused into ‘bioactive glass’. In doing so, they have demonstrated how the combination delivers longer-lasting antimicrobial wound protection compared with the conventional alternatives.

Bioactive glasses are among a series of synthetic biomaterials made from silicone that have typically been used for bone grafting. Indeed, the critical aspects of bioactive glass are its fibrous form which delivers a robust 3D porous structure and supports tissue growth.

Researchers investigated the impact of bioactive glass incorporated with ionic silver on biofilms formed by pseudomonas aeruginosa – a multi-drug resistant bacterium that is a frequent cause of infection in chronic wounds.

The studies showed that specific preparation, storage and application techniques can minimise the transformation of silver ions to silver chloride, therefore retaining antimicrobial activity.

For many years, silver has been acknowledged as a way of preventing or reducing the growth of biofilms – communities of bacteria – in open wounds. Now, however, silver-based treatments are becoming increasingly popular therapies against many antibiotic-resistant strains of bacteria.

The antimicrobial properties in question rely on silver remaining in an ionic form, allowing it to penetrate bacterial cell walls and disrupt their life cycle. The silver ions or nanoparticles in wound dressings, however, are predisposed to transforming to silver sulphide or silver chloride – which can decrease antimicrobial activity and hamper the success of treatment.

Having completed an Innovate UK funded programme– Innovation to Commercialisation of University Research – the team is now looking to proceed the material towards clinical approval.