Antimicrobial Activity of Monolayer and Multilayer Films Containing Polyhexamethylene Guanidine Sulphanilate

Abstract

The aim of this study was to determine the antimicrobial properties of multilayer films containing a PHMG sulphanilate (polyhexamethylene guanidine sulphanilate). Three types of films were selected: monolayer and three-layer films (both containing biocide) and market foil. The antibacterial activity of polyethylene film with PHMG sulphanilate was verified based on the guidelines of ISO 22196: 2007 (E): Plastics – Measurement of antibacterial activity on plastic surfaces. The antimicrobial efficacy of the monolayer film against Escherichia coli and Staphylococcus aureus was very good, equalling 6.25 log (100%) and 6.02 log (100%), respectively. It means that a total reduction in bacteria on the surface tested was achieved. The antimicrobial efficacy of the three-layer film against Escherichia coli was satisfactory and equaled 1.32 log (95.2%). The antimicrobial efficacy of this film against Staphylococcus aureus was very good and equaled 6.02 log (100%). The antifungal activity of polyethylene film with PHMG sulphanilate was verified based on the guidelines of ASTM G21 – 96: Standard practice for determining the resistance of synthetic polymeric materials to fungi. The fungal growth of Aspergillus niger, Chaetomium globosum and Trichoderma viride on the monolayer and three layer films was also inhibited, which means that the biocide in the films also exhibits antifungal activities. For the market foil, poor antibacterial efficacy against the bacteria and no antifungal activity against the fungi tested was observed.