Design of Antibacterial Surfaces and Interfaces: Polyelectrolyte Multilayers as a Multifunctional Platform

The adhesion and proliferation of bacteria on abiotic surfaces pose challenges related to human infection, including subsequent formation of antibiotic-resistant biofilms in both healthcare and industrial applications. Although the design of antibacterial materials is a longstanding effort, the surface properties that modulate adhesion of viable bacteria-the critical first step in biofilm formation-have been difficult to decouple. This partial and limited success is due chiefly to two factors. First, bacteria cells exhibit multiple, complex adhesion mechanisms that vary with bacteria strain, rapid genetic mutations within a given strain, and mutable environmental stimuli such as nutrient levels and fluid velocities. Second, there exist only a limited number of studies that systematically characterize or vary the physical, chemical, and mechanical properties of potential antimicrobial materials. Here, we briefly review the dominant strategies for antimicrobial material surface design, including the advantages and limitations of approaches developed via synthetic and natural polymers. We then consider polyelectrolyte multilayers (PEMs) as a versatile materials platform to adopt and integrate these strategies, as well is to elucidate the individual contributions of tunable material properties that limit viable bacteria adhesion. Together, these findings suggest that PEMs can be tailored to leverage the key advantages of bacterial adhesion resistance, contact killing, and biocide leaching strategies for a wide range of antimicrobial surface applications.