Physchem.cz

Highly efficient antimicrobial polymer nanofiber membranes and nanoparticles that use inactivation of a pathogen via photosensitized generation of singlet oxygen will be presented. The antimicrobial mechanism includes excitation of the photosensitizer encapsulated or externally bounded to nanomaterials by visible light, formation of its triplet states followed by energy transfer to triplet oxygen leading to short-living singlet oxygen formation. Since singlet oxygen is a great oxidant of biological targets, the antibacterial and antiviral effect is very powerful. The singlet oxygen-sensitized delayed fluorescence of a photosensitizer can be observed and used as a sensitive tool for detection of oxygen, imaging of singlet oxygen and distribution of a photosensitizer. Modifications of nanomaterials enabling size selective inactivation of pathogens, generation of singlet oxygen via thermolysis of endoperoxides or photoproducing NO radical or I₂ with the aim to increase their antimicrobial effect will be also mentioned.