Commercially available BIs designed to monitor sterilization processes should be correlated to the spore-resistance characteristics
of the products that they monitor. This correlation will ensure the most appropriate challenge to the sterilization process.
Ideally, the spore carrier of the BI should be composed of materials similar to those processed in the sterilizer. If this
situation is not feasible, D-value studies can be performed on component materials in the load to determine the substrate effect of the load. Once the
substrate effect is known, an appropriate BI can be selected and correlated to the process.
Table III: Summary of D-value study results on biological indicators using liquid pharmaceutical products and water for injection
(WFI) as the spore carrier.
Kurt McCauley is the research and development laboratory manager and John R. Gillis, PhD,* is the president and CEO of SGM Biotech, 10 Evergreen Dr., Suite E, Bozeman, MT 59715, tel. 406.585.9535, fax 406.585.9219,
*To whom all correspondence should be addressed.
Keywords: biological indicator, carrier material, resistance, spore suspension
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