On the use of laser surface engineering to modulate bacterial adhesion

Bacterial attachment to a surface is initiated by the absorption of molecules to the surface of a substratum forming what is known as a conditioning film. Furthermore, bacteria have evolved to become proficient at adapting to not only their extracellular but also environmental conditions, resulting in major health concerns and economic burden in both hospital and industrial environments. The benefits of CO2 and KrF laser surface engineering on the physical properties of polyethylene terephthalate (PET) films, and the subsequent effects on microbiological growth and conditioning film formation are presented. The influence of interfacial wetting on initial conditioning of the CO2 laser surface engineered PET film was analysed using contact angle measurements. Thereafter, the equation of state approach was used to explain the relationship between laser engineered surface characteristics, wettability characteristics and conditioning film formation. Bacterial adhesion analysis revealed a modulated bacterial response to the CO2 and KrF laser engineered patterns. This work presents the viability of laser surface engineering for creating anti-bacterial and bacteria-reactive surfaces, highlighting the potential for implementation of laser surface engineering in both the medical industry and food manufacturing industry.