Green-Synthesized Titanium Dioxide Nanoparticles Inhibit and Eradicate the Biofilms of Pathogenic Bacteria Through Intracellular ROS Production

Objectives: Bacterial infections, mainly due to rising antimicrobial resistance (AMR), are an immense global health threat, complicating treatment, prolonging illness, and increasing mortality. The WHO lists AMR as one of the major threats to human health. Biofilm plays a crucial role in AMR, protecting bacteria and promoting resistance. Targeting biofilms improves antibiotic efficacy and reduces chronic infections. Titanium dioxide nanoparticles (TiO2-NPs) have emerged as a promising candidate in drug delivery, diagnostics, and antimicrobial therapies due to their distinctive properties. Methods: Due to the challenge of AMR and the potential of green-synthesized nanoparticles, this study investigates antibiofilm activity and intracellular ROS production by TiO2-NPs produced from Linum usitatissimum seed extract. Results: The crystal size of LU-TiO2-NPs was determined as 8.024 nm, and TEM validated the average particle size as 14.30 +/- 5.93 nm. FTIR confirmed the presence of the O-Ti-O bond near 684 cm-1. LU-TiO2-NPs effectively inhibited biofilms, reducing biofilms of Staphylococcus aureus MTCC 3160 and Escherichia coli ATCC 25922 by 79.96% and 71.85%, respectively. Microscopic analysis also showed a reduction in bacterial adherence and colonization. This inhibition was supported by the reduction in exopolysaccharides, a major biofilm component. The biofilm inhibition was likely mediated by the induction of intracellular ROS production by LU-TiO2-NPs. Furthermore, LU-TiO2-NPs successfully eradicated established biofilms of both the Gram +ve and Gram -ve bacteria. Conclusion: The findings demonstrate that TiO2-NPs hold significant promise in tackling biofilm-associated bacterial infections and may prove beneficial in addressing the escalating problem of AMR.