Antimicrobial effects of the biological and synthetic micro-/nano-patterned arrays

Abstract

Bacteria present within a biofilm are often resistant to chemical antimicrobials. Dental plaque, a form of biofilm in the oral cavity, is the etiology of various dental diseases and infections. Rather than addressing the consequence of biofilm accumulation, an alternative approach to of controlling the biofilm is to impede or disrupt its formation. A variety of biomimetic micro-/nanoscale surface modifications are under investigation for their ability to impart biofunctionality and antibacterial property for synthetic materials.

The results demonstrated an antibiofouling property of the resin replicas that were able to kill Streptococcus mutans (S. mutans) and Porphyromonas gingivalis (P. gingivalis) in a similar manner as the natural gecko skin. A killing mechanism by rupture, compression and stretching of the bacterial cells was proposed.

In the second and third parts, an innovative, low-cost and facile approach was explored to mimic the surface micro-/nano-architecture of gecko skin, with controllable aspect ratio (AR), on a dental material, poly(methyl methacrylate) (PMMA). The nano-patterned PMMA films could act against several oral pathogens either as single-species biofilm or multi-species coaggregation, impeding their attachment and killing them by physical interplay.

The feasibility of further applications was tested by fabricating the surface nano-pattern on a synthetic material, polystyrene (PS), against Escherichia coli (E. coli). That fourth and last part of this study demonstrated that PS nano-patterned film also possessed antibiofouling and bactericidal action.

In conclusion, the micro-/nano-scale gecko or gecko-inspired synthetic arrays exhibited antimicrobial effects, against both single-species biofilms and multi-species coaggregation.