Different antibacterial mechanisms of titania nanotube arrays at various growth phases of E. coli
(1. College of Biology, Hunan University, Changsha 410082, China;
2. Hunan Key Laboratory of Oral Health Research & Xiangya Stomatological Hospital & Xiangya School of Stomatology, Central South University, Changsha 410008, China;
3. Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China;
4. Department of Oral and Maxillofacial Surgery, The Second Xiangya Hospital, Central South University, Changsha 410011, China)
2. Hunan Key Laboratory of Oral Health Research & Xiangya Stomatological Hospital & Xiangya School of Stomatology, Central South University, Changsha 410008, China;
3. Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China;
4. Department of Oral and Maxillofacial Surgery, The Second Xiangya Hospital, Central South University, Changsha 410011, China)
Abstract: To clarify the antibacterial behavior at early adhesion, two titania nanotube (TNT) arrays were fabricated on polished commercially pure titanium (Ti), and the interaction mechanisms between TNT arrays and the model bacteria (Escherichia coli, E. coli) were investigated. The results show that TNT arrays exhibit a significant early antibacterial effect, which is highly related to the surface free energy and nano-topography. The underlying antibacterial mechanisms include: (1) the anti-initial-attachment effect at the lag phase (0-4 h); (2) the anti-proliferation and physical bactericidal effects at the logarithmic phase (4-12 h); (3) the reduced antimicrobial properties probably due to the overgrowth of bacteria on TNT arrays at the stationary phase (12 h and then).
Key words: titania nanotube array; Escherichia coli; antibacterial mechanism; bacterial adhesion; bacterial proliferation