Dispersive liquid-liquid microextraction method coupled with gas chromatography for determination of dimethylcydosiloxane in water samples

A novel method for the determination of three dimethylcydosiloxanes in water samples was developed by using dispersive liquid-liquid microextraction(DLLME) coupled with gas chromatography-flame ionization detection(GC-FID).The factors relevant to the microextraction efficiency,such as type and volume of extraction solvents and dispersion agent,the extraction time and salt effect were investigated and optimized.Under the optimized extraction conditions,a good linear relationship was obtained in the range of 5～100 μg /L of the analytes with the correlation coefficients greater than 0.99,the detection limits were 2～4 μg/L,the enrichment factors ranged from 165 to 170 and the relative standard deviations(RSD) were in the range of 4.7%～8.0%,respectively.The developed method was applied to the determination of three dimethylcydosiloxanes in tap water and lake water samples,the average recoveries were 108.1%～112.8% with RSD ranged from 4.9% to 8.2%.