Growth inhibition of Staphylococcus Aureus by a combined treatment of ZnO nanoparticles and femtosecond laser light

Recently, efforts have been made to create a transparent ceramic cranial implant comprised of nanocrystalline yttriastabilized zirconia (nc-YSZ) that will provide optical access to the brain. This has been referred to as Window to the Brain (WttB) in the literature. WttB will allow the use of laser and photonic treatments and diagnostics in areas with difficult optical access in the brain. For example, the WttB platform would allow for non-invasive antibacterial treatments based on laser light. This is important as conventional antibiotics are prevented to reach the brain tissue due to the blood brain barrier. Moreover, infection is still one of the frequent cranial implant complications. In most cases a second surgery is required to replace the infectious implant. To address potential infections in the WttB platform, we have studied the antibacterial effect of commercial Zinc Oxide (ZnO) nanoparticles and femtosecond laser light on bacterial solutions of Staphylococcus aureus (S. aureus). Infrared (1030nm) laser light was used to enhanced the antibacterial effect of ZnO nanoparticles by irradiating bacterial solutions of S. aureus with low power ultrashort laser pulses (890mW, 230fs).