Worldwide natural and synthetic estrogens can be found in environmental and drinking water due to high pharmaceutical consumption and excretion. Estrogens, such as estrone, 17-β-estradiol, estriol and the synthetic 17-α-ethynyl estradiol are believed to play a major role in the interference with the hormonal system of exposed water organisms, but the potential consequences to humans remain still uncertain. For the sensitive analysis of estrogens in environmental matrices, an extraction and purification step is often necessary, which is often time consuming. With the Online SPE Solution time and labor can be reduced and sample throughput enhanced because the whole analysis can be done with one HPLC instrument and without offline sample preparation.
This work demonstrates the enhanced sensitivity and analysis of estrogens by Online SPE compared to direct inject methods on a routine and a high end mass spectrometer. The sensitive analysis of estrogens in drinking water is shown with four different methods performed on two mass spectrometers.
With the option of a high volume injection kit (4.5 ml), it is possible to be sensitive as low as sub- 1ng/L with a routine mass spectrometer. With a high end mass spectrometer detection limits of 0.05 ng/L were observed. Excellent linearity was determined for all compounds for a wide range of concentrations on both mass spectrometers. It was observed that the high end (MS) compared to the routine LC/MS System was up to 10 times more sensitive.