Neutralising Pharmaceutical Diluent (NPD)

Neutralising Pharmaceutical Diluent (NPD)

This is a general-purpose neutralising diluent used particularly in the pharmaceutical industry.
Lecithin, L-histidine and Tween 80 are present to inactivate surface disinfectants such as quaternary ammonium compounds, phenols, aldehydes (including formaldehyde), hexachlorophene and ethanol.
The diluent may be used in sampling surfaces and equipment (including endoscopes) to detect the presence of surviving microorganisms after disinfection.
The presence of the surfactant Tween 80 also helps release adherent organisms from surfaces being tested.

Additional Information



Shelf Life (days)

Storage Temp (°C)





Product Description

Organisms Ref. No Result
Escherichia coli ATCC 8739 Stable viability
Staphylococcus aureus ATCC 6538 Stable viability
Pseudomonas aeruginosa ATCC 9027 Stable viability
Candida albicans ATCC 10231 Stable viability
Bacillus subtilis ATCC 6633 Stable viability


Recommended incubation: Incubate aerobically at 20 ± 5°C for 45 ± 5 minutes. Before and after counts checked.