title: Simultaneous determination of most prescribed antibiotics in multiple urban wastewater by SPE-LC-MS/MS.
abstract: A rapid analytical method was developed for the application of a long-term monitoring (>one year) of the most prescribed and often in hospitals used antibiotics in diverse wastewaters of an urban sewage treatment plant (STP). Additionally to the selected multi-class antibiotics amoxicillin, penicillin V and piperacillin (penicillins), cefotaxime and cefuroxime (cephalosporins), azithromycin, clarithromycin and roxithromycin (macrolids), ciprofloxacin and levofloxacin-ofloxacin (fluoroquinolones), clindamycin (lincosamide), doxycycline (tetracycline), sulfamethoxazole (sulfonamide) and trimethoprim (dihydrofolate reductase inhibitor), the bioactive metabolite clindamycin-sulfoxide, the reserve antibiotic vancomycin (glycopeptide) and as tracer of the STP the anticonvulsant carbamazepine and the antifungal fluconazole were involved. The analytical method combines a low-sample-volume solid phase extraction (SPE), followed by a chromatographic separation using a reversed phase (RP) and hydrophilic interaction liquid chromatography (HILIC) technique, respectively, coupled to a triple quadrupole mass spectrometer. Detection was performed with multiple reaction monitoring (MRM) measured with positive electrospray ionization (ESI+). The extraction efficiency of different SPE cartridges and optimized pH-values of the preparation procedure were tested. Finally, the extraction of antibiotics was realized with the Oasis HLB cartridge and a pH adjustment at 3.5. An external calibration curve in diluted blank urine was used for quality control of the sample set of daily composite samples of the STP for the duration of one year monitoring. The squared coefficient of determination (r(2)) in the concentration range (20-20,000ng/L or 100-100,000ng/L) of the calibration curves for the method was higher than 0.99 for all determined substances. The limit of quantification (LoQ) ranged between 0.8ng/L (azithromycin) and 245.1ng/L (vancomycin). Furthermore, a standard addition was used for quantification in wastewater samples. The process efficiencies ranged from 20% (doxycycline) to 134% (cefuroxime) in influent samples and from 31% (doxycycline) to 171% (cefuroxime) in effluent samples of the STP. All selected substances have been found in wastewater samples. Cefuroxime, doxycycline, levofloxacin, piperacillin, sulfamethoxazole and carbamazepine showed highest concentrations up to 6.2μg/L.
authors.affiliation: Institute of Clinical Pharmacology, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Fiedlerstrasse 27, D-01307 Dresden, Germany; Research Association Public Health Saxony and Saxony Anhalt, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Fiedlerstrasse 33, D-01307 Dresden, Germany. Electronic address: julia.rossmann@tu-dresden.de.
authors.forename: Julia
authors.initials: J
authors.lastname: Rossmann
authors.affiliation: Institute of Clinical Pharmacology, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Fiedlerstrasse 27, D-01307 Dresden, Germany.
authors.forename: Sara
authors.initials: S
authors.lastname: Schubert
authors.affiliation: Institute of Clinical Pharmacology, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Fiedlerstrasse 27, D-01307 Dresden, Germany; Research Association Public Health Saxony and Saxony Anhalt, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Fiedlerstrasse 33, D-01307 Dresden, Germany.
authors.forename: Robert
authors.initials: R
authors.lastname: Gurke
authors.affiliation: Institute of Clinical Pharmacology, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Fiedlerstrasse 27, D-01307 Dresden, Germany.
authors.forename: Reinhard
authors.initials: R
authors.lastname: Oertel
authors.affiliation: Institute of Clinical Pharmacology, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Fiedlerstrasse 27, D-01307 Dresden, Germany; Research Association Public Health Saxony and Saxony Anhalt, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Fiedlerstrasse 33, D-01307 Dresden, Germany.
authors.forename: Wilhelm
authors.initials: W
authors.lastname: Kirch
mesh_terms: D000900:Anti-Bacterial Agents / Q000032:analysis* / Q000737:chemistry / Q000302:isolation & purification; D002853:Chromatography, Liquid / Q000379:methods*; D016014:Linear Models; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012722:Sewage / Q000737:chemistry*; D052616:Solid Phase Extraction / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000737:chemistry / Q000302:isolation & purification
chemical_list: D000900:Anti-Bacterial Agents; D012722:Sewage; D014874:Water Pollutants, Chemical
keywords: Antibiotics; HILIC; Prescription; RP; SPE-HPLC–MS/MS; Wastewater