title: Analysis of β-blockers in groundwater using large-volume injection coupled-column reversed-phase liquid chromatography with fluorescence detection and liquid chromatography time-of-flight mass spectrometry.
abstract: Atenolol, nadolol, metoprolol, bisoprolol and betaxolol were simultaneously determined in groundwater samples by large-volume injection coupled-column reversed-phase liquid chromatography with fluorescence detection (LVI-LC-LC-FD) and liquid chromatography-time-of-flight mass spectrometry (LC-TOF-MS). The LVI-LC-LC-FD method combines analyte isolation, preconcentration and determination into a single step. Significant reductions in costs for sample pre-treatment (solvent and solid phases for clean up) and method development times are also achieved. Using LC-TOF-MS, accurate mass measurements within 3 ppm error were obtained for all of the β-blockers studied. Empirical formula information can be obtained by this method, allowing the unequivocal identification of the target compounds in the samples. To increase the sensitivity, a solid-phase extraction step with Oasis MCX cartridge was carried out yielding recoveries of 79-114% (n=5) with RSD 2-7% for the LC-TOF-MS method. SPE gives a high purification of β-blockers compared with the existing methods. A 100% methanol wash was allowed for these compounds with no loss of analytes. Limit of quantification was 1-7 ng/L for LVI-LC-LC-FD and 0.25-5 ng/L for LC-TOF-MS. As a result of selective extraction and effective removal of coextractives, no matrix effect was observed in LVI-LC-LC-FD and LC-TOF-MS analyses. The methods were applied to detect and quantify β-blockers in groundwater samples of Almería (Spain).
authors.affiliation: Department of Analytical Chemistry, University of Almería, La Cañada de San Urbano, Almería, Spain.
authors.forename: María M
authors.initials: MM
authors.lastname: Galera
authors.forename: Piedad P
authors.initials: PP
authors.lastname: Vázquez
authors.forename: María del Mar P
authors.initials: Mdel M
authors.lastname: Vázquez
authors.forename: María Dolores G
authors.initials: MD
authors.lastname: García
authors.forename: Carmen F
authors.initials: CF
authors.lastname: Amate
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000032:analysis*; D002853:Chromatography, Liquid; D056148:Chromatography, Reverse-Phase; D005453:Fluorescence; D060587:Groundwater / Q000737:chemistry*; D013058:Mass Spectrometry; D013997:Time Factors
chemical_list: D000319:Adrenergic beta-Antagonists