Catz led Oxford researchers develop new ultrasound-triggered treatment for antibiotic-resistant infections
A team at the University of Oxford has created a new drug delivery method using ultrasound-activated nanoparticles to break down bacterial biofilms — a major cause of chronic, treatment-resistant infections.
To address this, a team from Oxford’s Department of Engineering Science and the Nuffield Department of Orthopaedics, Rheumatology, and Musculoskeletal Sciences (NDORMS) have engineered antibiotic-loaded nanoparticles. When activated by ultrasound, these rapidly vaporise and thus both physically disrupt biofilms and release drugs directly at the infection site. Ultrasound can be precisely focused deep inside the body, which is a key advantage for targeting infections non-invasively.
Professor Eleanor Stride, Professor of Biomaterials, St Catherine’s College, University of Oxford and Principal Investigator of the project, said:
‘Innovative solutions are desperately needed to extend the action of life-saving antibiotics. Our findings are very promising, as treatment of chronic infections associated with biofilm production continues to be a challenge in the face of spreading antimicrobial resistance worldwide. The methods we used in this study were designed with clinical use in mind, and we look forward to developing this system further for application in healthcare settings.’
The nanoparticles were tested on 10 clinical bacterial strains, including E. coli and MRSA, using four antibiotics. In non-biofilm bacteria, combining nanoparticles with ultrasound cut the required antibiotic dose by over 10 times.
In biofilm-related infections, the effect was even stronger — reducing required doses by over 40-fold and completely eliminating bacteria at clinically safe levels. The system was also highly effective against persister cells, cutting the dose needed by 25 times compared to standard antibiotics.
Biofilms play a key role in hard-to-treat conditions like chronic wounds, UTIs, cystic fibrosis lung infections, and acne. The team is now working to scale up nanoparticle production for clinical trials.
The study ‘Repurposing antimicrobials with ultrasound-triggered nanoscale systems for targeted biofilm drug delivery’ has been published in the journal npj Antimicrobials and Resistance.
Find out more about how researchers at the University of Oxford are tackling antimicrobial resistance on the AMR Network Homepage.