An improved derivatization protocol for the simultaneous determination of alkylphenol ethoxylates and brominated flame retardants with heptafluorobutyric anhydride under triethylamine amine base was investigated. The derivatization reaction was completed in 30 min at 50°C using hexane as solvent. Under these conditions, it was observed that alkylphenol ethoxylates and tetrabromobisphenol A were derivatized successfully in the presence of hexabromocyclododecane, lower congeners of polybrominated biphenyls and polybrominated diphenyl ethers. The improved protocol was applied to recovery of analytes of interest from simulated water samples after solid phase extraction. The recoveries achieved were above 60%. The limit of detection and limit of quantification ranged from 0.01-0.20 µg/ℓ and 0.05-0.66 µg/ℓ, respectively.