Fast Fabrication of Superhydrophobic Titanium Alloy as Antibacterial Surface Using Nanosecond Laser Texturing

The method for fast fabrication of superhydrophobic surfaces was proposed to resist the formation of biofilm of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) for orthopedic and dental implants. Laser beam machining with nanosecond pulsed laser (Nd:YAG) was used to fabricate pit structure on Grade-5 Ti-6Al-4V alloy followed by annealing (at 300 degrees C with different time scales) in order to reduce the transition time from hydrophilic to superhydrophobic surface generation. Field emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD) techniques were used to characterize the textured samples. The surface wettability of plain and textured samples was measured by the sessile drop method using goniometer. The biofilm formation was qualitatively and quantitatively evaluated by FE-SEM and crystal violet binding assay, respectively. The biofilm formation was observed on plain (hydrophilic) surface for both the types of bacteria, whereas significantly less biofilm formation was observed on the laser textured (superhydrophobic) surfaces. The proposed method helps in reducing the risk of infection associated with implants without using cytotoxic bactericidal agents.