Biocompatible mechano-bactericidal nanopatterned surfaces with salt-responsive bacterial release

Area of Science:

• Biomaterials Science
• Nanotechnology
• Surface Chemistry
• Infectious Disease

Background:

• Bio-inspired nanostructures offer mechanical bactericidal properties, but suffer from debris contamination.
• Existing antibacterial surfaces often rely on chemical agents, risking bacterial resistance.
• Contamination of nanostructured surfaces compromises long-term antibacterial efficacy.

Purpose of the Study:

• To develop a biocompatible, mechano-bactericidal nanopatterned surface with salt-responsive bacterial releasing behavior.
• To create a dual-functional surface that kills bacteria and facilitates the removal of dead bacterial debris.
• To evaluate the selective biocidal activity and biocompatibility of the functionalized surface.

Main Methods:

• Grafting salt-responsive polyzwitterionic (polyDVBAPS) brushes onto a bio-inspired nanopattern surface.
• Investigating salt-triggered configuration changes of polymer brushes for bacterial release.
• In vitro testing of biocompatibility with red blood cells and mammalian cells.
• In vivo evaluation in a rat subcutaneous implant model for histocompatibility and anti-contamination.

Main Results:

• The dual-functional surface demonstrated high mechano-bactericidal efficiency in low ionic strength conditions.
• Dead bacterial residuals were effectively removed in high ionic strength (1 M NaCl) solution via extended polymer chains.
• The nanopatterned surface exhibited selective biocidal activity against bacteria over eukaryotic cells.
• In vitro and in vivo studies confirmed excellent biocompatibility and prevention of perioperative contamination.

Conclusions:

• The developed salt-responsive nanopatterned surface provides a dual-action antibacterial strategy, combining mechanical killing with debris removal.
• This antibiotic-free approach offers a promising alternative for long-term efficacy in combating bacterial infections, particularly perioperative ones.
• The selective biocidal activity and biocompatibility highlight its potential for safe and effective biomedical applications.