Colonisation Resistant Surfaces

Abstract

Microorganisms that form biofilms can be used to improve processes, particularly bioremediation and metabolic processes (da Silva & de Martinis, 2013). However, microbial colonisation on submerged surfaces, equipment used in the aquaculture and food industries and on hospital surfaces can be a major problem, both for equipment deterioration and human health. Biofilms are often more resistant to antibiotics and cleaning agents due to the protection conferred by the extrapolymeric substance (EPS), the altered metabolic state of cells deep within the biofilm layers, and the altered gene expression due to the adaptive stress responses of the microorganism (van Houdt & Michiels, 2010; Dapa et al., 2013). Controlling biofilm production through the use of chemicals and disinfectants is not always effective. The best way to circumvent cleaners and disinfectants from polluting the environment or generating resistant microorganisms is to create surfaces that an innately antimicrobial. Polyaniline (PANI) is a conducting polymer (CP) that can be altered by copolymerisation with substituted anilines that contain functional side groups, allowing the creation of functionalised PANI (fPANI) that show antimicrobial properties (Gizdavic-Nikolaidis et al., 2011a). The fPANI P2ABA.MSA was incorporated into poly(styrene-ethylene/butylene-styrene) and polypropylene films to create a surface that showed antimicrobial properties against both Staphylococcus aureus and Escherichia coli after a single use but loses it’s antimicrobial potential after repeated microbial challenges depending on the chemicals that the films are cleaned with.