BT50/6 Biological Indicator Spore Strips

BT50/6 / Spore Strips Biological Indicator for Steam and Formaldehyde sterilization processes. Geobacillus stearothermophilus (ATCC 7953) 10^6 spores per strip.

The envelope containing Bionova® BT50 Spore Strip is specifically designed to control Steam 121 ºC-135 ºC (Steam) and Formaldehyde (Form) sterilization processes. Spore strips should be incubated in Bionova® MC20-2 or MC1020-2 Growth Medium tube or in appropiate Growth medium for Geobacillus stearothermophilus ATCC 7953 growth.

If the sterilization process was not effective, MC20-2 or MC1020-2 Growth Medium will turn to yellow after incubation between 55-62ºC, thus indicating the existence of living Geobacillus stearothermophilus spores on the strips.

If the sterilization process was effective, MC20-2 or MC1020-2 Indicating Medium will remain its original color. A final readout should therefore be performed after 24 hours of growth medium incubation between 55-62ºC for Steam sterilization processes control, or 48 hours between 55-62ºC for Formaldehyde sterilization processes control.

Instructions for use

1. Identify Bionova® BT50 envelope by writing on its back the sterilizer number (in case of having more than one), load number and processing date.
2. Pack it in an appropriate package along with material to be sterilized, according to recommended sterilization practices. Place the envelope in those areas you a priori consider more inaccessible for sterilizing agent. A typical problematic area is the load center.
3. Sterilize as usual.
4. After sterilization process has finished, remove Bionova® BT50 envelope from the package for processing and incubation.
5. Tear up the envelope at one end very carefully under sterility conditions (eg. laminar flow cabinet) and transfer the spore strip with a sterile clamp to MC20-2 or MC1020-2 Growth Medium tube or any other appropriate growth medium.
   1. WARNING: Avoid spore strip contact with any kind of surface including the outer part of Growth Medium tube and of Bionova® BT50 envelope.
   2. IMPORTANT: Use latex gloves and a mask when transferring spore strips from the envelope to growth medium tube.
   3. Use a spore strip which has not been subjected to the sterilization process as a positive control each time a processed strip is incubated. Both, processed spore strip and the strip used as positive control must belong to the same batch. Positive control guarantees that the incubation was carried out under appropriate conditions.
6. Incubate processed spore strips along with the strip used as a positive control between 55-62ºC during a maximum of 24 hours for Steam or 48 hours for Formaldehyde. It is advisable to make observations every 10 hours.

Color change of MC20-2 or MC1020-2 indicating medium to yellow means a failure of the sterilization process.

If after 24 hours (Steam) or 48 hours (Form) no color change is visible on MC20-2 or MC1020-2 growth medium, the result is negative (i.e. the sterilization process was effective). MC20-2 or MC1020-2 Growth Medium used for incubating the spores strips which have not been sterilized (positive control) should turn to yellow for the results to be valid.