Chapter 15: Nanofibers and Nanocomposite Films for Singlet Oxygen-Based Applications

The development of photoactive nanomaterials producing singlet oxygen, ¹O₂, has blossomed as a field of great interest because of the ease with which their functionality is switched on and off by light, with a quick response, and their ability to do so without introducing other reactants into the system. In this chapter, we address the developing area of polymer nanofibers and nanocomposite films containing photosensitizers (PS) that are encapsulated or attached to the surface, with an emphasis on their photophysical properties, their ability to produce ¹O₂, and their potential use in constructing multifunctional platforms with photoantibacterial, photoantiviral, and photo-oxidative properties. Polymer nanofibers have several advantages over bulk polymers including their large specific surface area and high porosity, light weight, low cost, mechanical flexibility, light-transparency, and small diameters, which range from tens to hundreds of nanometers. The selection of polymers with high oxygen permeability and surface hydrophilicity (wettability) is crucial for achieving the efficient photo-oxidation effect of ¹O₂. Important experimental data that illuminate the correlation of these two parameters and performance are discussed, and examples from our laboratory and others are summarized. Potential directions for further developments are also highlighted.