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. Copyright © 2008 Society of Chemical Industry