Fiber-optic singlet oxygen [¹O₂ (¹Δ _g)] generator device serving as a point selective sterilizer

A novel hollow-core fiber-optic device has been created to improve traditional Type II heterogeneous photo-oxidations, which usually require external light and oxygen sources. This device incorporates an internal supply of light and flowing oxygen with a porous photosensitizer-end capped configuration to produce singlet oxygen, delivered through the fiber tip. It achieved a steady-state singlet oxygen concentration of around 20 fm near the probe tip. Being portable and maneuverable, this device facilitated simple disinfection studies, achieving complete inactivation of Escherichia coli within 2 hours in small aqueous samples. However, after about 12 hours of use, the probe tip experienced photobleaching, necessitating baking and sensitizer reloading for reuse.