Laser Diode Thermal Desorption/Atmospheric Pressure Chemical Ionization Tandem Mass Spectrometry Analysis of Selected Steroid Hormones in Wastewater: Method Optimization and Application

A rapid and reliable method enabling high-throughput sample analysis for quicker data generation, detection, and monitoring of eight selected steroid hormones in water matrixes was developed and validated. Our approach is based on a novel sample introduction method, the laser diode thermal desorption/atmospheric pressure chemical ionization (LDTD/APCI) coupled to tandem mass spectrometry (MS/MS). The optimization of instrumental parameters and a method application are presented. Our method was successfully applied to spiked effluent wastewater in the low-nanogram per liter concentrations with total analysis time reduced to seconds (15 s) using LDTD/APCI-MS/MS compared to minutes with traditional liquid-chromatography coupled to tandem mass spectrometry (LC-MS/MS) following solid-phase extraction (SPE). The instrumental detection limit,,; for LDTD/APCI-MS/MS ranged from 5 to 24 mu g L-1 and from 13 to 43 ng L-1 for the method detection limits. Calibration curves in wastewater matrix showed good linearity (R-2 > 0.99), and precision (intraday and interday) was below 20%. This work demonstrates that LDTD/APCI-MS/MS could be used for fast and effective quantitative analysis of emerging contaminants in different water matrixes with reduced cost by eliminating the chromatography step used in traditional LC-MS/MS.