Culture medium with pH indicator for G. stearothermophilus

MC20-2 / Culture Medium with pH indicator for growth of Geobacillus stearothermophilus (ATCC 7953) bacterial spores (2 ml). Turns from Purple to Yellow. Readout: 24/48 hours.

To test growth of Geobacillus stearothermophilus ATCC 7953 bacterial spores used for monitoring Steam, Plasma or Vaporized Hydrogen Peroxide and Formaldehyde sterilization processes.

Instructions for use

1. Identify Bionova® MC20-2 tube by writing on the label the sterilizer number (in case of having more than one), load number and processing date.

2. Open the envelope containing the spore carrier under sterile conditions (for example: laminar flow) and transfer using a sterile clamp to MC20-2 growth medium tube. WARNING: Avoid contact between carrier and any surface, including the outside of the culture medium tube.

IMPORTANT: Use latex gloves and a mask when transferring the spore carrier from the envelope to the MC20-2 Culture Medium tube. Every time a processed carrier is incubated, a non-sterilized spore carrier should be used as a positive control. Both, the processed carrier and the carrier used as positive control must belong to the same batch. A positive control assures proper incubation conditions.

3. Incubate the spore carrier inside the MC20-2 Culture Medium between 55-62 ºC. Color change of the growth indicator medium to yellow shows the sterilization process has failed. A final negative result is obtained if there is no color change of the MC20-2 Culture Medium at 24 hours of incubation (spores subject to Steam/VH2O2 processes) or 48 hours of incubation (spores subject to Formaldehyde processes), meaning the sterilization process has been effective.

The color of the MC20-2 Indicator Medium used to incubate the unprocessed spore carrier (positive control) should turn to yellow for the result to be valid.