Toward Efficient Low-Temperature Ozone Gas Sterilization of Medical Devices

Abstract

ABSTRACT An ozone generation system using V-UV excimer lamps (172nm) and an optical measurement system based on the Beer–Lambert law were developed for an efficient low-temperature (15 °C-30 °C) sterilization of medical devices. Ozone concentrations between 100 and 1ʹ000 ppm (0.2–2 g/Nm3) were generated and the impact of several variables on the sterilization outcome were studied. The survivor curves of the sterilization process were obtained for biological indicators (BIs) inoculated with Geobacillus stearothermophilus spores. A lag phase was observed before the start of the actual sterilization which followed first-order log-linear kinetics. The results demonstrated the feasibility to sterilize medical devices with ozone at ambient temperatures, reducing the consumption of resources and the cost of sterilization.