Plasma-Etched Vertically Aligned CNTs with Enhanced Antibacterial Power.

Area of Science:

• Materials Science
• Nanotechnology
• Microbiology

Background:

• Multidrug-resistant bacteria pose a significant global health threat.
• Novel antibacterial strategies beyond conventional antibiotics are urgently needed.
• Carbon nanotubes (CNTs) present potential as advanced antibacterial platforms.

Purpose of the Study:

• To investigate the antibacterial and antibiofilm efficacy of tailored vertically aligned carbon nanotubes (VA-CNTs).
• To explore the role of nanomorphology modification via plasma etching in antibacterial activity.
• To identify optimal VA-CNT configurations for inactivating key bacterial pathogens.

Main Methods:

• Fabrication and characterization of VA-CNTs with varied nanomorphologies using plasma etching (Ar/O2).
• Microscopic and spectroscopic techniques to analyze VA-CNT topography.
• Assessment of antibacterial activity against planktonic and biofilm cultures of Pseudomonas aeruginosa and Staphylococcus aureus.
• Evaluation of bacterial cell viability reduction.

Main Results:

• Plasma-etched VA-CNTs demonstrated significant antibacterial efficacy against both P. aeruginosa and S. aureus.
• VA-CNTs treated with Ar/O2 etching achieved 100% and 97% reduction in cell viability, respectively.
• Antibacterial activity is attributed to a synergistic combination of mechanical damage and reactive oxygen species (ROS) production.
• Effective inactivation of both planktonic and biofilm bacterial forms was observed.

Conclusions:

• Tailored VA-CNTs are highly effective antibiotic-free platforms for bacterial inactivation.
• Plasma etching allows controlled modification of VA-CNT nanomorphology for enhanced antibacterial properties.
• These findings pave the way for developing self-cleaning surfaces and novel antimicrobial strategies.