Water sterilization at sterility assurance levels exceeding 10−6 has been achieved with a novel high temperature and pressure sterilization system (HAPSS) capable of continuous-flow sterilization. The tested sterilizer produces >2,000 L/day and does not require filters, moving parts, or regular maintenance and can operate for multiple years with only water and standard voltage/amperage electricity. Sterility assurance levels were determined using Geobacillus stearothermophilus spores with inactivation experiments as a function of temperature and flow rate (i.e., duration/dosage at given temperature). Sterility of 1.0 × 104 CFU/mL G. stearothermophilus spore suspensions was achieved at the highest water flow rate of 1.4 L/min at 140 and 130 °C. The low cost and maintenance-free operation of HAPSS is envisioned to impact water sterilization needs of developing nations, hospitals, and commercial point of use applications.
- bacterial spores
- Geobacillus stearothermophilus
- water sterilization
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