Liquid-Infused Silicone As a Biofouling-Free Medical Material

Abstract

There is a dire need for infection prevention strategies that do not require the use of antibiotics, which exacer- bate the rise of multi- and pan-drug resistant infectious organisms. An important target in this area is the bacterial attach- ment and subsequent biofilm formation on medical devices (e.g., catheters). Here we describe non-fouling, lubricant-infused slippery polymers as proof-of-concept medical materials that are based on oil–infused polydimethylsiloxane (iPDMS). Pla- nar and tubular geometry silicone substrates can be infused with non-toxic silicone oil to create a stable, extremely slippery interface that exhibits exceptionally low bacterial adhesion and prevents biofilm formation. Analysis of a flow culture of Pseudomonas aeruginosa through untreated PDMS and iPDMS tubing shows at least an order of magnitude reduction of bio- film formation on iPDMS, and almost complete absence of biofilm on iPDMS after a gentle water rinse. The iPDMS materials can be applied as a coating on other polymers or prepared as simply as taking a silicone tubing and immersing it in a sili- cone oil, and are compatible with traditional sterilization methods. As a demonstration, we show the preparation of sili- cone-coated polyurethane catheters and significant reduction of Escherichia coli and Staphylococcus epidermidis biofilm formation on the catheter surface. This work represents an important first step towards a simple and effective means of preventing bacterial adhesion on a wide range of materials used for medical devices.