Surface Tension Modulation-Induced Sterilization of TiO₂ Nanorods for Antibacterial Applications

Bacteriostasis is of great concern in the fields of medical health and food safety. Nanostructured surfaces have received special attention due to their biocompatibility and nontoxicity and have the potential in the fields of medical devices, implantable materials, food packaging, production pipelines, and so on. However, the exact mechanism is still being debated, and the presence of a microenvironment around bacteria is often overlooked, which could be better utilized. Here, we would like to introduce a simple green sterilization method assisted by TiO2 nanorods in the process of room temperature drying. Surface tension is created by the simple way of natural evaporation of liquids, helping the nanorods to better kill bacteria. By using this system, the bacterial mortality of Escherichia coli O157:H7 reached 91.92 +/- 6.08%. This system was also effective against Staphylococcus aureus belonging to Gram-positive bacteria. The concepts and antimicrobial systems described in this study proposed a feasible and effective strategy for constructing efficient and safe physical sterilization surfaces. At the same time, the sterilization mechanism of the nanorod surface was explored. In most cases, the system was realized spontaneously without involving antimicrobials or some additional conditions; therefore, it could be conveniently applied in more antimicrobial application scenarios. The study further highlighted that the presence of aquatic environments for bacteria should be given more attention, rather than being ignored.