On-demand biofilm removal by shape-memory triggered local changes in surface topography

Area of Science:

• Biomaterials Engineering
• Surface Science
• Microbiology

Background:

• Bacterial biofilms on medical devices cause persistent, antibiotic-resistant infections.
• Current treatments are often ineffective and contribute to antibiotic resistance.
• Previous strategies altered bulk material shape, limiting applications.

Purpose of the Study:

• To investigate biofilm removal using localized topographic changes on shape-memory polymers (SMPs).
• To develop a method that removes biofilms without altering the bulk material's shape.
• To assess the impact of triggered topographic changes on biofilm removal and antibiotic susceptibility.

Main Methods:

• Fabrication of acrylate-based SMPs with a transition temperature of 40°C.
• Creation of micron-scale square patterns on SMP surfaces via hot compression.
• Triggering shape recovery with a moderate temperature change in an aqueous environment.
• Quantification of biofilm removal for *Pseudomonas aeruginosa* and *Escherichia coli*.

Main Results:

• Effective on-demand biofilm removal achieved (~70% for *P. aeruginosa* and *E. coli*).
• Biofilm removal occurred solely through localized topographic changes, preserving bulk material integrity.
• Triggered shape recovery enhanced the antibiotic susceptibility of remaining bacterial cells.

Conclusions:

• Localized topographic changes on SMPs offer a viable strategy for on-demand biofilm removal.
• This approach avoids bulk material deformation, broadening potential applications.
• The findings contribute to developing advanced antifouling materials for medical devices and industrial settings.