Selective determination of sartan drugs in environmental water samples by mixed-mode solid-phase extraction and liquid chromatography tandem mass spectrometry

Abstract

Herein, a method for the simultaneous determination of the currently prescribed sartan drugs (eprosartan, EPR; olmesartan, OLM; losartan, LOS; candesartan, CAN; telmisartan, TEL; irbesartan, IRB; and valsartan, VAL), and the biodegradation product valsartan acid (VALA), in water samples (raw and treated wastewater, river and tap water) was developed. Solid-phase extraction (SPE) and ultra-performance liquid chromatography (UPLC) tandem mass spectrometry (MS/MS) were employed as concentration and determination techniques, respectively. Different sorbents and elution solvents were tested for sample preparation. Under optimized conditions, samples at neutral pH (6 to 8 units) were concentrated using mixed-mode (reversed-phase and anionic exchange) cartridges. Thereafter, the sorbent was washed with 5 mL of a methanol: water (1:1) solution, dried under a nitrogen stream and compounds were eluted with 2 mL of methanol: NH3 (98:2). The accuracy of the method (accounting for SPE efficiency and matrix effects during electrospray ionization) was investigated using solvent-based calibration standards. Global recoveries, obtained for different water matrices (tap, river, treated and raw wastewater), ranged from 82% to 134%, with standard deviations between 2 and 18%. LOQs varied from 2 to 50 ng L -1 . Analysis of un-spiked samples confirmed: (1) the incomplete removal of sartans at sewage treatment plants (STPs), (2) the formation of VALA during municipal water treatment, and (3) the presence of VALA in the processed tap water samples. Additional findings of the current study are the detection of hydroxylated derivatives of the sartan drugs IRB and LOS in wastewater, and the E-Z isomerization of EPR in environmental water samples.

Determination of 107 Pesticide Residues in Wolfberry with Acetate-buffered Salt Extraction and Sin-QuEChERS Nano Column Purification Coupled with Ultra Performance Liquid Chromatography Tandem Mass Spectrometry

“…In recent years, mass spectrometry (MS) technology has been developing continuously, among which LC coupled with tandem MS (LC-MS/MS) is an effective and sensitive method for the detection of pesticide residues [25,26]. Common sample pretreatment techniques including liquid-liquid extraction (LLE) [27], solid phase extraction (SPE) [28,29], microwave-assisted extraction (MAE) [29,30], supercritical fluid extraction (SFE) [31], accelerated solvent extraction (ASE) [32,33,34], magnetic solid phase extraction (MSPE) [35,36], gel permeation chromatography (GPC) [37,38,39], as well as the QuEChERS method (quick, easy, cheap, effective, rugged and safe) which was firstly published by Anastassiades et al in 2003 [40]. Nowadays, the QuEChERS protocol has been widely used for the determination of pesticide residues due to its significant advantages [41].…”

Solid-phase extraction and fractionation of multiclass pollutants from wastewater followed by liquid chromatography tandem-mass spectrometry analysis

“…The second SPE setup considered concentration of water samples, at neutral pH, using a weak anionic exchange MM sorbent (WAX) [ 12 ]. In the elution step, this sorbent was connected to a pure cationic exchanger (SCX) cartridge.…”

“…Moreover, they allow the use of fractionated elution protocols, recovering compounds retained through the RP mechanism and those establishing electrostatic interactions with sorbent in different fractions [ 9 ]. Thus, cleaner extracts are obtained for the latter group of compounds, which turns in lower MEs [ 10 – 12 ]. The scientific literature contains previous successful applications of different types of MM sorbents to the selective extraction of basic (i.e., illicit drugs [ 13 ] and pharmaceuticals [ 11 ]), or acidic compounds (such as anti-hypertension drugs [ 12 ] and perfluorinated carboxylic and sulfonic acids [ 14 ]) from water samples.…”

“…Thus, cleaner extracts are obtained for the latter group of compounds, which turns in lower MEs [ 10 – 12 ]. The scientific literature contains previous successful applications of different types of MM sorbents to the selective extraction of basic (i.e., illicit drugs [ 13 ] and pharmaceuticals [ 11 ]), or acidic compounds (such as anti-hypertension drugs [ 12 ] and perfluorinated carboxylic and sulfonic acids [ 14 ]) from water samples. Most of these studies have been compiled in a recent review [ 7 ].…”

Feature-based molecular networking for identification of organic micropollutants including metabolites by non-target analysis applied to riverbank filtration

“…The retention behavior of the compounds was compared to different RP-HPLC-MS studies [38,[41][42][43] and, except for candesartan, the elution order of the sartans was conclusive (ESM Figure S8). Candesartan eluted between irbesartan and valsartan, but in literature, it was either found to elute before [38] or after [43] both compounds depending on the applied column, as mobile phases were the same in both studies (water and methanol with 0.1% FA). Therefore, we assumed that candesartan elution was very sensitive to the chosen column and chromatographic conditions, e.g., the chosen eluents.…”