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Updated: Jul 5, 2026
Protocols for Testing the Toxicity of Novel Insecticidal Chemistries to Mosquitoes
Published on: February 13, 2019
A novel assay reveals the blockade of esterases by piperonyl butoxide
Anna C Khot1, Georgina Bingham, Linda M Field
1Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, UK.
Background:
Conventional in vitro assays sometimes fail to reveal esterase inhibition by piperonyl butoxide (PBO), although synergism studies suggest loss of esterase-mediated sequestration of insecticide does take place. A new in vitro assay has been devised that routinely reveals binding between PBO and these esterases.
Results:
The new 'esterase interference' assay detects the blockade of resistance-associated esterases in a species, Myzus persicae Sülzer, where this has not previously been seen. The assay also demonstrates directly the protective effect esterases may confer to target sites of insecticides.
Conclusion:
The new assay reveals esterase blockade by PBO and thus has the potential to be used as a high-throughput screening method for other potential synergists.
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