Accelerated neutral atom beam (ANAB) and gas clustered ion beam (GCIB) treatment of implantable device polymers leads to decreased bacterial attachment in vitro and decreased inflammation in vivo

Infections at the placement site of biomaterial-based devices and subsequent scar formation results in morbidity, which may require revision surgery. Biomaterials intended for permanent implantation in the body need to be biologically inert to avoid excessive foreign body response and to reduce bacterial attachment. In this study, we show that polymeric materials commonly used in medical devices, including polyetheretherketone (PEEK) and polypropylene, treated by gas cluster ion beam (GCIB) or by accelerated neutral atom beam (ANAB) result in a nanoscale-modified surface topography that changes the ability of extracellular proteins to bind. This leads to decreased bacterial attachment and an attenuated inflammatory response using both in vitro and in vivo assays. Differential adsorption of extracellular proteins to the polymeric surface improved the competitive attachment of osteoblasts over bacteria, without resorting to growth factor of antibiotic use.