Piperonyl butoxide 
Content Handbook N
Ouline of method
Method, see CIPAC H, p 239.
The sample is extracted by refluxing with xylene. The piperonyl butoxide content is determined by capillary gas chromatography using flame ionisation detection and internal standard.
The method is suitable for determining piperonyl butoxide in impregnated insecticidal nets in the presence of deltamethrin (Note 1).
The method extension is usable for LN-formulations.
Note 1: A deltamethrin peak will not be visible on the chromatogram at the conditions given.