Decontamination from water pollutants and pathogens by electrospun nanofibers doped with heavy-atom-free borafluorene-BODIPY photosensitizers

A heavy-atom-free and non-toxic spirocyclic C-BODIPY singlet oxygen photosensitizer was successfully incorporated into electrospun polymeric nanofibers. Optimization of the material composition revealed that polycaprolactone (PCL), an FDA- and EMA-approved, biodegradable, easily accessible, and cost-efficient polymer, doped with BODIPY at a concentration of only 0.15 wt %, is an efficient photocatalyst for the degradation of the pharmaceutical agents ranitidine, propranolol, and cimetidine, selected as model water pollutants. The obtained nanofibers showed smooth and uniform morphology along with very high durability and resistance toward oxidation, remaining active even after 20 reaction cycles. EDX, ToF-SIMS and XPS analyses confirmed the homogenous distribution of BODIPY within the polymeric matrix. Furthermore, the materials showed significant photoinactivation of Staphylococcus aureus under white light irradiation compared to the control experiment performed without irradiation. These findings highlight the potential of the electrospun PCL nanofibers as optimal matrix for the immobilization with singlet oxygen photosensitizers and subsequent application in the decontamination of water from pollutants and pathogens.