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Keywords
- tobacco mosaic virus (TMV) (2)
- aseptic parameters (1)
- bi-enzyme biosensor (1)
- biosensor (1)
- capacitive field-effect sensor (1)
- enzyme cascade (1)
- enzyme-logic gate (1)
- gaseous hydrogen peroxide (1)
- glucose oxidase (GOx) (1)
- horseradish peroxidase (HRP) (1)
- multi-sensing platform (1)
- penicillinase (1)
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- sterility (1)
- turnip vein clearing virus (TVCV) (1)
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Within the present work a sterilization process by a heated gas mixture that contains hydrogen peroxide (H₂O₂) is validated by experiments and numerical modeling techniques. The operational parameters that affect the sterilization efficacy are described alongside the two modes of sterilization: gaseous and condensed H₂O₂. Measurements with a previously developed H₂O₂ gas sensor are carried out to validate the applied H₂O₂ gas concentration during sterilization. We performed microbiological tests at different H₂O₂ gas concentrations by applying an end-point method to carrier strips, which contain different inoculation loads of Geobacillus stearothermophilus spores. The analysis of the sterilization process of a pharmaceutical glass vial is performed by numerical modeling. The numerical model combines heat- and advection-diffusion mass transfer with vapor–pressure equations to predict the location of condensate formation and the concentration of H₂O₂ at the packaging surfaces by changing the gas temperature. For a sterilization process of 0.7 s, a H₂O₂ gas concentration above 4% v/v is required to reach a log-count reduction above six. The numerical results showed the location of H₂O₂ condensate formation, which decreases with increasing sterilant-gas temperature. The model can be transferred to different gas nozzle- and packaging geometries to assure the absence of H₂O₂ residues.