Optimization of Ultrasonic-Assisted Extraction of Inorganic Arsenic in Sargassum fusiforme (Harv.) by Response Surface Methodology

Ultrasonic-assisted extraction was utilized to extract inorganic arsenic from Sargassum fusiforme(Harv.) by hydrochloric acid.Hydride generation atomic fluorescence spectrometry(HG-AFS) was used for the determination of inorganic arsenic.Based on the single factor tests,the Box-Behnken central composite design and response surface methodology(RSM) were adopted to obtain the optimal conditions for the extraction of inorganic arsenic from Sargassum fusiforme(Harv.),using fluorescence intensity as the response value and the extraction concentration,extraction temperature and time as the factors.The results showed that the optimum extraction conditions of inorganic arsenic were the extraction concentration 6.6 mol/L,extraction temperature 53.4 ℃ and time 24.4 min.Under these conditions,the fluorescence intensity was 675.51,and the content of inorganic arsenic was 4.78 mg/kg.