title: New way to quantify multiple steroidal compounds in wastewater by comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry.
abstract: The applicability of comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry to the screening of steroidal compounds in wastewater is demonstrated. Advanced software was utilized to identify unknown compounds in complex two-dimensional chromatograms exploiting retention indices and two different mass spectral databases. Response factors calculated as a function of the individual mass spectra of six commercial standards at different concentrations were used to develop a model allowing the quantitation of all steroidal compounds identified in the sample. The model, based on partial least squares regression equations, provided good accuracy (prediction error < 16%) in the quantitation of steroidal compounds, so offering a valuable alternative to conventional quantitation methods where reference compounds are required for the verification of analytical measurements. Special attention was paid to the development of an exhaustive sample preparation method for the separate analysis of conjugated and free steroids in both water phase and suspended solid particles. The method, including the exploitation of chemometrics, was successfully applied to the determination of steroidal compounds in effluent and influent waters collected at a local wastewater treatment plant.
authors: Laboratory of Analytical Chemistry, Department of Chemistry, P.O. Box 55, FI-00014 University of Helsinki, Finland.
authors: Matias
authors: M
authors: Kopperi
authors: José
authors: J
authors: Ruiz-Jiménez
authors: Janne I
authors: JI
authors: Hukkinen
authors: Marja-Liisa
authors: ML
authors: Riekkola
mesh_terms: D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D016018:Least-Squares Analysis; D012680:Sensitivity and Specificity; D013256:Steroids / Q000032:analysis*; D062065:Wastewater / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D013256:Steroids; D062065:Wastewater; D014874:Water Pollutants, Chemical