title: Determination of acidic drugs in sewage water by gas chromatography-mass spectrometry as tert.-butyldimethylsilyl derivatives.
abstract: A procedure is described for the determination of five acidic non-steroidal anti-inflammatory pharmaceuticals (ibuprofen, naproxen, ketoprofen, tolfenamic acid and diclofenac) in sewage water. The analytical method involves the concentration of water samples using a solid-phase extraction polymeric sorbent, functionalized with N-vinylpyrrolidone. Analytes were eluted with ethyl acetate. derivatized using N-methyl-N-(tert.-butyldimethylsilyl)trifluoroacetamide (MTBSTFA) and analyzed by GC-MS. Influence of time, temperature and volume of MTBSTFA in the yield of the derivatization step were studied in detail using a factorial central composite design. Quantification limits of the analytical procedure for 500 ml of sewage water ranged from 20 to 50 ng/l. Recoveries from 90 to 115% were found for sewage water samples spiked with the studied compounds at the low ng/ml level. Results obtained for real samples show the presence of ibuprofen and naproxen in both influent and effluent of a sewage water treatment plant.
authors.affiliation: Departamento de Química Analítica, Nutrición y Bromatología, Universidad de Santiago de Compostela, Avda, de las Ciencias s/n, Santiago de Compostela 15782, Spain.
authors.forename: I
authors.initials: I
authors.lastname: Rodríguez
authors.forename: J B
authors.initials: JB
authors.lastname: Quintana
authors.forename: J
authors.initials: J
authors.lastname: Carpinteiro
authors.forename: A M
authors.initials: AM
authors.lastname: Carro
authors.forename: R A
authors.initials: RA
authors.lastname: Lorenzo
authors.forename: R
authors.initials: R
authors.lastname: Cela
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000032:analysis*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D012722:Sewage / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D012722:Sewage; D014874:Water Pollutants, Chemical