GC-MS Determination of Trace Amounts of Estrogens in Water with Derivatization

A method of GC-MS for simultaneous determination of 8 estrogens, i.e., estradiol, estrone, estriol, estradiol valerate, diethylstilbestrol,ethynyl estradiol, bisphenol A and 4-nonylphenol in water was proposed. Sample was extracted with ethyl acetate and purified on the HLB column,then derivatized with TMS or HFBA. The derivatized product was dissolved with n-hexane. The DB-5MS capillary column was used for GC separation and the full-scanning mode and selected ion monitoring mode were adopted in MS determination. Linear relationship between values of peak area and mass concentration of 8 estrogens were obtained in the same range of 20.0-1 000 μg·L-1, with detection limits (3S/N) in the range of 0.1-0.5 μg·L-1. The proposed method was applied to the analysis of water sample, giving values of recovery in the range of 71%-103% and RSD′s (n=6) in the range of 4.2%-15%.