MAXIMISING RECOVERY OF MICROORGANISMS FROM SURFACES

 

• Certificate of conformity supplied with each pack
• Manufactured to ISO 9001:2000
• Conforms to ISO 18593:2004
• Forms part of HACCP and GMP programmes
• Guaranteed 2% fill tolerance
• Letheen neutralises residual sanitisers
• Neutralizes quaternary ammonium disinfectants via lecithin and polysorbate 80
• Ensures accurate microbial recovery from treated surfaces
• Self-standing tube minimizes contamination risk
• Sterilized by gamma irradiation

 

If swabs samples are taken from surfaces which have been disinfected, there may still be traces of biocide which can react with and reduce the count of microorganisms present at the time of sampling. Such microorganisms may have been part of, and protected by a surface biofilm, and the action of swabbing loosens them and exposes them to the biocide. This will result in a false low count, and failure to detect a potential hazard for subsequent food or beverage production. It is essential, therefore, and may be mandatory, that any residual disinfectant on surfaces is neutralised at the time of sampling by first wetting the swab in an appropriate neutralising solution.

 

The Medical Wire & Equipment (MWE) NRSII™ Transwab with Letheen Broth is a ready-to-use environmental and product sampling system designed for the recovery of microorganisms from surfaces and materials that have been exposed to disinfectants containing quaternary ammonium compounds. The Letheen Broth medium neutralizes residual disinfectant activity, ensuring the accurate recovery of viable microorganisms for subsequent culture or enumeration. The Transwab® format provides a sterile, self-contained, and easy-to-handle solution ideal for hygiene monitoring in food, pharmaceutical, cosmetic, and clinical environments.

During environmental sampling, microorganisms collected on the swab are maintained in the neutralizing Letheen medium, which inactivates residual quaternary ammonium disinfectants (QACs) while preserving microbial viability. The sample is then transported to the testing laboratory for microbiological enumeration, detection, or identification.

 

Procedure

1. Label the NRSII™ Transwab® vial with sample identification details.
2. Unscrew the blue cap and remove the swab aseptically.
3. Swab the target surface (typically 100 or 200 cm²), rotating the swab to ensure complete coverage.
4. Return the swab to the vial and secure the cap tightly.
5. Transport the sample to the testing laboratory under controlled temperature conditions.
6. Upon receipt, vortex or agitate the swab in the broth before culture or analysis.

 

 

Shelf Life and Storage

• Shelf life: 18 months from date of manufacture
• Storage conditions: +5 °C to +25 °C
• Do not freeze
• Protect from direct sunlight and humidity
• Sterilized by gamma irradiation

 

 

Resources

   NRS II Brochure

 

 

Ordering Details

Stock code                  Description                                                                         Pack Size

MW794                           NRSII Transwab – Letheen Broth 1mL                                      50

MW792                           NRSII Transwab – Letheen Broth 5mL                                      50

MW793                           NRSII Transwab –  Letheen Broth 10mL                                   50

 

Shelf Life:  2 Years from date of manufacture

Storage: Room Temperature