Published: 15th September 2008
HOSPITAL superbugs could be combated by painting walls with a "killer paint" that destroys bacteria, according to biochemists at Manchester Metropolitan University.
Researchers from MMU have developed new paints containing titanium dioxide nanoparticles that can be used on walls, ceilings and other surfaces to kill bacteria when exposed to fluorescent lights.
The team tested different formulations of the new paint under different types and intensities of light on the Escherichia coli (E. coli) bacteria.
They report that paints with higher concentrations of titanium dioxide nanoparticle were better able to kill bacteria and that ordinary fluorescent lights were sufficient to kill all E. coli.
Titanium dioxide is common in white paints and under UV light reacts with any water molecules on the particle surface to attack other bacteria.
Now a team led by Professor Norman Allen and Professor Joanna Verran in the Centre for Materials Science Research have set out to study whether white paint could be modified into a new weapon against superbugs in hospitals.
The team began by exposing samples of E. Coli to paints containing no additives but high concentrations – up to 80% – of titanium dioxide. They also experimented with paints lower in titanium dioxide, but with paint additives such as calcium carbonate.
In the course of those experiments, they found that the paint additives can block the killer properties of titanium dioxide.
"If calcium carbonate was present, the ‘kill-rate’ dropped by up to 80%," said lead researcher Lucia Caballero, who observed that additives block some titanium dioxide particles from becoming agitated by UV.
The results suggest paint could be made into a bacteria killer by adding more titanium dioxide and removing fillers.
But striking a balance between paint that is suitably deadly, but still long-lasting, could prove difficult and more research is needed.
For more about the work of the Centre for Materials Science Research, go to www.sci-eng.mmu.ac.uk/bchs/chemistry/research/centre_for_materials_science_research