Abstract
A rapid and sensitive method for the determination of 4โfluoroโ3โphenoxybenzaldehyde cyanohydrin (FPBC) and 4โfluoroโ3โphenoxyโbenzaldehyde (FPB) in honey samples using ultrasonically assisted extraction and gas chromatography with electron capture detection (GCโECD) has been developed. The different factors affecting the efficiency of the extraction were carefully optimized. The honey sample was extracted with a mixture of hexane and dichloromethane (v/v, 1:1) utilizing the ultrasonically assisted technique and cleaned up by solidโphase extraction on Oasis HLB cartridges. The eluate was evaporated to dryness and residues were reconstituted to 1.0 mL with hexane and determined by GCโECD. The calibration curves of fortified samples showed acceptable linear response (R^2^ >0.99) over a range of 3โ100 ng/g for FPBC and FPB in seven replicate determinations of six concentrations, respectively, and analysis of variance (ANOVA) with a lackโofโfit test was performed to validate the regression data. Overall average recoveries ranged from 90.9 to 106.2% for honey samples. The detection limits were 0.9 ng/g for FPBC and 1.0 ng/g for FPB, respectively. This method can be successfully applied to routine determination of two degradation products of flumethrin in honey samples.