Chapter 7. Photodynamic Antimicrobial Polymers

Photodynamic antimicrobial polymers are materials that exert an antimicrobial effect when irradiated with a specific light source. This light-triggered activity is considered advantageous, as it allows fine control of the antimicrobial effect, minimising the possible adverse effects and propagation of antimicrobial resistance commonly associated with overexposure to antimicrobial agents. Extensive research has been conducted on incorporation of photosensitisers into or onto polymeric supports to produce potent photodynamic antimicrobial materials. Photosensitisers are agents that generate cytotoxic reactive oxygen species (ROS) when illuminated with visible light in the presence of oxygen. The ability of these generated ROS to eradicate a wide range of microorganisms has led to the incorporation of photosensitisers into a range of polymers, with a vast array of potential applications explored. This chapter focuses on photosensitiser-incorporated polymers, with consideration of the factors that can be altered to optimise antimicrobial activity. This is followed by a detailed discussion on current research and the development of these unique materials for the production of light-activated antimicrobial biomedical devices or for anti-infective surfaces in clinical settings.