Evaluation of the Decimal Reduction Time of a Sterilization Process in Pharmaceutical Production

  • Jeffrey Eisele
  • Amy Racine
  • Mauro Gasparini


Consider measuring the effectiveness of sterilization during the production of a pharmaceutical substance. The decimal reduction time, D-value, of a steriliza­tion process is defined to be the time required to reduce the number of microor­ganisms present by a factor of 10. Because the issue of concern is the rate of bacterial death this process is often referred to as “Death Kinetics.” Different methods for sterilization are possible depending on the nature of the pharmaceu­tical product, for example, heat treatment. Since the D-value depends to a large extent on environmental conditions, it is necessary to determine experimentally the substance specific D-value for each substance that is sterilized by means of moist heat. If the D-value of the substance is the same as that of a reference substance, typically water, the sterilization process is deemed successful.


Test Substance Microbial Count Sterilization Process ASCII File Individual Assay 
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Copyright information

© Springer Science+Business Media New York 2001

Authors and Affiliations

  • Jeffrey Eisele
    • 1
  • Amy Racine
    • 1
  • Mauro Gasparini
    • 2
  1. 1.Department of BiostatisticsNovartis Pharma AGBaselSwitzerland
  2. 2.Dipartimento di MatematicaPolitecnico di TorinoTorinoItaly

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