A*STAR Institute of Bioengineering and Nanotechnology researchers have developed a one-step coating that blocks protein growth and kills surface-bound bacteria on silicone medical devices such as catheters.

The synthetic technique combines biomimetic surface adhesion and antimicrobial capabilities into a brush-like polymer film. The coatings, or ‘polymer brushes,’ are arrays of macromolecular chains that bind to surfaces and modify properties such as bioadhesion.

Researcher Yi Yan Yang and co-workers are working to improve polymer brushes, using biodegradable materials called aliphatic polycarbonates. The team developed a ‘living’ ring-opening polymerization that attaches antimicrobial molecular units and PEG chains to the polycarbonate backbone with high precision. Experiments revealed that catheters coated with the polycarbonate–PEG film eradicated Staphylococcus bacteria and had excellent blood compatibility.

Now, the researchers have added three key components to the polycarbonate backbone: effective antimicrobial cations, PEG chains for antifouling, and dopamine groups that stick to silicone rubber in a manner similar to adhesive proteins found in mussel shells.

The new polymer brush may be used to prevent infection in intravascular catheters.