engleski

Simultaneous determination of sulfonamide, fluoroquinolone and macrolide antimicrobials in wastewater using solid-phase extraction and liquid chromatography/tandem mass spectrometry (LC/MS/MS)

A sensitive and highly selective method for the simultaneous determination of sulfonamide, fluoroquinolone and macrolide antimicrobials in wastewater has been developed. The analytes were enriched from wastewater samples by solid-phase extraction using hydrophilic-lipophylic balance (HLB) cartridges and subsequently eluted with methanol. After evaporation of the extract to dryness, the residue was re-dissolved in water containing 0.1 % of formic acid and analysed by reversed-phase liquid chromatography coupled to electrospray ionization-tandem mass spectrometry (ESI-MS/MS). The detection of all target analytes was performed in positive mode using multiple reaction monitoring (MRM). Quantification of sulfonamides as well as fluoroquinolones and macrolides was performed using several deuterated sulfonamides as internal standards. Recoveries of individual antimicrobials from water samples spiked at 1  g/L were in the range from 46 to 133 % with relative standard deviations between 2 and 30 %. Detection limits based on 200 ml-water samples ranged from 0.2 to 12 ng/L. The application of the method for the analysis of real municipal wastewater samples indicated that co-extracted organic matrix might have a significant impact on chromatographic behaviour and quantification of those antimicrobials, which possess positively charged groups. In such cases, matrix effects were alleviated by appropriate dilution of the final extract. The method was applied for the analysis of wastewater samples from Croatia and Bosnia and Herzegovina.

-

nije evidentirano