Development of a multi-hormone analysis method by LC-MS/MS for environmental water application using diffusive gradient in thin films
Résumé
An analysis method for four families of hormones (estrogens, progestins, androgens and prostaglandins), dedicated to an efficient water monitoring with passive sampling, was developed using a liquid chromatography tandem mass spectrometry with triple quadrupole coupling and universal electrospray ionisation. Thirteen natural and synthetic hormones in ultra-pure water could be analysed in a single run according to the French Standard NF T90-210: calibration range of 0.1 (except for 17 beta-Estradiol, Estriol, Estrone and Diethylstilbestrol, from 0.5 mu g/L; and Ethinylestradiol, from 1 mu g/L) to 20 mu g/L with linear regressions (R2 >= 0.96), maximum accuracy deviations of 30% at intermediate fidelity for three concentration references (1, 10 and 20 mu g/L) and instrumental LOQs from 0.05 to 1 mu g/L. The stability of 11 hormones (10 mu g/L) was studied under several storage conditions and sample evaporation. All selected hormones were stable for 60 days at -18 degrees C, 7 days at 4 degrees C and 7 days at 20 degrees C but continued drying flow after evaporation should be avoided, especially for 17 alpha-Estradiol, Estrone and Diethylstilbestrol. Observed matrix effects using o-DGT extracts (diffusive gradient in thin-film sampler for polar organics) containing an environmental matrix varied from 24 to 92% but all matrix effects were corrected with IS use. Therefore, the developed method, coupled with o-DGT, was tested with the o-DGT deployment in rivers. Using diffusion coefficients from the literature or lab determined, the concentrations in the rivers varied for Estrone from 1.8 ng/L to 2.5 ng/L, and for Androstenedione from 0.4 to 1.1 ng/L.