Multi heart-cutting two-dimensional liquid chromatography–atmospheric pressure photoionization-tandem mass spectrometry method for the determination of endocrine disrupting compounds in water

The multi-heart-cutting two-dimensional liquid chromatography–tandem mass spectrometry method using atmospheric pressure photoionization has been developed and successfully validated for the determination of nine endocrine disrupting compounds in river water. The method is based on the use of two different reverse-phase columns connected through a six-port two-position switching valve equipped with a 200 μl loop. An orthogonal separation was achieved by proper selection of stationary phases, mobile phases, and the use of a gradient elution in both dimensions. The method shows excellent performance in terms of accuracy (86.2–111.1%), precision (intra-batch: 6.7–11.2%, inter-batch: 7.2–13.5%), and sensitivity (1.2–7.1 ng l−1). Twenty real samples collected from the Loučka and the Svratka rivers were analyzed, the studied compounds were found in all Svratka samples (9.7–11.2 ng l−1 for β-estradiol, 7.6–9.3 ng l−1 for estrone, and 24.6–38.7 ng l−1 for bisphenol A).

► A significant decrease of matrix effect was achieved by 2D-chromatography.
► PQRI database was used to evaluate “difference” in selectivities of columns.
► Gradient elution substantially improved orthogonality of the separation system.
► Cation radicals have been utilized in API-MS/MS detection.
► The method was successfully validated according to FDA guidance.