You are here:  

• Print

Development of dual anti-adhesive/antimicrobial medical devices.

Andrew Hook (Pharmacy), Roger Bayston (Medicine), Luisa Martinez-Pomares (Medicine), Laurence Burroughs (Pharmacy) and Waheed Ashraf (Medicine).

The issue

All surgery carries a risk of infection, but medical devices such as hip replacements and catheters can be a particular problem. Medical devices like these can become covered in biofilms, groups of microorganisms such as bacteria that are adhered to surfaces. When microorganisms become biofilms it becomes much harder to treat associated infections. Patients can then experience long-term and recurring infections requiring frequent antimicrobial treatments with an inconsistent dose. This kind of treatment is bad for patients and can allow microorganisms to adapt, leading to resistance. It also exposes bacteria in the “normal flora” sites such as gut and skin to selective pressure, giving rise to infections with Pseudomonas, Candida and Clostridium difficile.

The research

Recent research by Andrew Hook and others has discovered a new class of polymers resistant to biofilm formation. In addition, Roger Bayston has developed a method to impregnate silicone catheters with multiple antimicrobials to prevent a wide range of types of infection with long-lasting activity, a step change from the previous methods of antimicrobial impregnation.By combining these methods medical devices could be made to be far more resistant to biofilms, but there are many challenges to do doing so. This research will attempt to answer four key questions:

• Can antimicrobials be delivered through an anti-adhesive coating?
• Can the release rate of antimicrobials be controlled by varying the properties of the coating?
• Does the optimal loading methodology change with the addition of a coating?
• Do preliminary tests suggest these devices are immunocompatible?

The impact

Medical device associated infections, particularly catheters where much of the previous research has been focused, are persistent issues for clinicians and patients. Our current treatment solutions are inefficient, use a great deal of antimicrobials and increase the chance of microorganisms developing resistance. Combating the growth of biofilms on medical devices might allow us to achieve several aims:

• reduce the infection rates for patients;
• increase the longevity of medical devices;
• reduce our use of antimicrobials and reduce the development of resistance.

If successful, the combination approach will be of great benefit to urinary catheter users, for whom there is no effective alternative, and could be applied to other implants such as endotracheal and nasogastric tubes, central venous catheters and wound drains.

If you are interested in finding out more about this research or about Bridging the Gaps please be in contact with Harry Moriarty h.moriarty@nottingham.ac.uk in the first instance.