Accurate mass screening of pharmaceuticals and fungicides in water by U-HPLC–Exactive Orbitrap MS

Abstract

The use of pharmaceuticals in livestock production is a potential source of surface water, groundwater and soil contamination. Possible impacts of antibiotics on the environment include toxicity and the emergence of antibiotic resistance. Monitoring programs are required to record the presence of these substances in the environment. A rapid, versatile and selective multi-method was developed and validated for screening 43 pharmaceutical and fungicides compounds, in surface and groundwater, in one single full-scan MS method, using benchtop U-HPLC-Exactive Orbitrap MS at 50,000 (FWHM) resolution. Detection was based on calculated exact masses and on retention time. Sample volume, pH conditions and solid-phase extraction (SPE) sample clean-up conditions were optimized. In the final method, 74 % of the compounds had recoveries higher than 80 %, 15 % of the compounds had recoveries between 60 % and 80 %, and 7 % of the compounds had recoveries between 40 % and 50 %. One of the compounds (itraconazole) had a recovery lower than 10 % and nystatin was not detected. The level of detection was 10 ng L(-1) for 61 % of the compounds, 50 ng L(-1) for 32 % and 100 ng L(-1) for 5%. In-house validation, based on EU guidelines, proves that the detection capability CCβ is lower than 10 ng L(-1) (for β error 5 %) for 37 % of the compounds, lower than 50 ng L(-1) for 35 % of the compounds and lower than 100 ng L(-1) for 14 % of compounds. This study demonstrates that the ultra-high resolution and reliable mass accuracy of Exactive Orbitrap MS permits the detection of pharmaceutical residues in a concentration range of 10-100 ng L(-1), applying a post target screening approach, in the multi-method conditions.

Contaminants in water: non-target UHPLC/MS analysis

“…2. Post-target screening or suspect screening methods, where all the compounds eluted from the chromatographic column are measured by MS and the m/z of target analytes, are extracted afterward from the total ion chromatogram (TIC) Ibáñez et al 2008;Nurmi and Pellinen 2011;Chitescu et al 2012;Díaz et al 2012). The analytes are examined after the analysis by plotting a narrowwindow extracted ion chromatogram (nw-XIC) of 20-50 mDa.…”

Future perspectives in Orbitrap™-high-resolution mass spectrometry in food analysis: a review

“…For example, the use of pharmaceuticals in livestock production is a potential source of contamination of surface water, groundwater and soil. Chitescu et al, (2012a) have screened for 43 pharmaceuticals and fungicides in surface and groundwater, in one single full-scan MS method, using UHPLC-Exactive™ MS at 50,000 (FWHM) resolution. Their method was fully validated having a sensitivity of 10-100 ng/L.…”

Quality Control of Biomarkers: From the Samples to Data Interpretation

“…The ability of the methodology for the verification of non-molecular ions, which arise from adduct formation, and the possibility of distinguishing isomers could also be demonstrated. Careful examination of the raw data and the use of masses for predicted metabolites produced an extension of the metabolite list [35].…”