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A simple, fast, and sensitive method is proposed for the analysis of 32 priority substances (PS) from EU Water Framework Directive (WFD) and the first Watch List in effluents of wastewater treatment plants (EWW), surface waters (SW) and drinking waters (DW). Dispersive liquid-liquid microextraction (DLLME) and gas chromatography coupled to tandem mass spectrometry (GC-MS/MS) is used. For DLLME, a mixture of 1,1,2-trichloroethane as extraction solvent (75 µL) and acetonitrile as disperser solvent (3.2 mL) is proposed. The method was validated in EWW, SW and DW, showing satisfactory accuracy values ranging from 90% to 104%, good precision (relative standard deviation, RSD%, lower than 13%) and uncertainty values between 7% and 34%. Regarding sensitivity, method limits of quantification (MLOQs) of 4.8, 5.2 and 8.8 ng L−1 for DW, SW and EWW, respectively, were obtained. The developed method was applied to analyze PS in water from effluents of waste water treatment plants (WWTPs), surface water of the Llobregat River and its main tributaries (Catalonia, NE Spain) and drinking water from a Drinking Water Treatment Plant (DWTP). Moreover, the efficiency of treatment plants (DWTP, WWTP) on the elimination of PS was evaluated. Only 3 PS (lindane, terbutryn and dicofol) were detected, being terbutryn the compound found at the highest levels (up to 493 ng L−1 in EWW samples). Regarding environmental quality standard (WFD) for terbutryn in surface waters, only one sample, the Rubí stream (431 ng L−1), showed levels of terbutryn higher than maximum allowable concentration (340 ng L−1).

A total of seventy samples of drinking water were tested for non-controlled and illicit drugs. Of these, 43 were from Spanish cities, 15 from seven other European countries, three from Japan and nine from seven different Latin American countries. The most frequently detected compounds were caffeine, nicotine, cotinine, cocaine and its metabolite benzoylecgonine, methadone and its metabolite EDDP. The mean concentrations of non-controlled drugs were: for caffeine 50 and 19 ng L(-1), in Spanish and worldwide drinking water respectively and for nicotine 13 and 19 ng L(-1). Illicit drugs were sparsely present and usually at ultratrace level (

Various types of glycosaminoglycans (GAGs) including heparins, chondroitin sulfates, dermatan sulfate and hyaluronic acid were studied from their proton nuclear magnetic resonance (1H NMR) spectra using chemometric techniques. Despite the complexity of the 1H NMR signals, data analysis using principal component analysis enabled the different GAG classes to be distinguished and permitted their classification according to their chemical structure. The analysis of the composition of the major disaccharide unit and other relevant chemical structures in the heparin samples was performed using partial least squares regression.

This paper shows the use of three-way data analysis methods to improve resolution and quantification in poorly separated peaks from capillary zone electrophoresis (CZE). Second-order data (data matrices) obtained with a diode array detector (DAD) are analyzed. There is a large overlap in the electrophoretic time domain and the data do not have a strict trilinear structure. These shortcomings might hinder the mathematical resolution. However, three-way methods allow the pure electrophoretic profiles of the analytes to be recovered in an unknown mixture, even in the presence of uncalibrated interferences. Furthermore, the analyte can be quantified in unknown mixtures with reasonable accuracy using pure standards. As an example, ebrotidine metabolites were chosen to test the method.

A 1H NMR method for the quantification of dermatan sulfate impurities in heparin industrial samples is proposed. The method is based on the analysis of 1H NMR spectral data by multivariate calibration. The 1H NMR spectra of heparin and dermatan sulfate standards showed characteristic profiles. Thus, differences in the methyl peaks of acetamido groups of heparin and dermatan sulfate were greatly advantageous for the analysis. Other hydrogens of the sugar ring were also relevant in this study. Thus, the determination of dermatan sulfate by multivariate calibration depended on all these differences. Partial least squares regression (PLS) was chosen as the calibration method. In addition, a data standardization procedure was developed in order that 1H NMR spectra registered with different instruments operating under different measurement conditions were comparable. The quantification of dermatan sulfate in the samples was satisfactory, with an overall prediction error of 6%.

Fifty samples of finished drinking waters (FDWs) from Spain covering 12 million inhabitants were tested for 53 pharmaceuticals pertaining to 12 different Anatomical Therapeutic Chemical (ATC) classification system codes. The studied compounds are a combination of most commonly consumed pharmaceuticals with other barely reported in the literature. Five compounds, azithromycin, clarithromycin, erythromycin, sulfamethoxazole, and ibuprofen were tentatively identified by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) in some samples (2 to 15 %), but only ibuprofen and azithromycin could be confirmed when analyzed by liquid chromatography–high-resolution mass spectrometry (LC-HRMS) with a quadrupole-Orbitrap instrument. Concentration levels of ibuprofen in the positive samples ranged from 12 to 17 ng/L (n = 6) while for azithromycin values from 5 to 9.5 ng/L (n = 3) were found. Ibuprofen fragmentation behaviour in different mass spectrometry instrument configurations (triple quadrupole, quadrupole-ion trap, and quadrupole-Orbitrap) was evaluated.

The efficiency and the reproducibility of different solid-phase adsorbents such as C18 cartridges, C18 and poly(styrene-divinylbenzene) (PS-DVB) membrane extraction disks were evaluated for the extraction of phenols from water at μg 1−1 concentration levels. Liquid chromatography with electrochemical detection (LC-ED) was used for the analysis of the organic extracts. A phosphate buffer-acetonitrile-methanol mixture as mobile phase and coulometric detection at + 750 mV were used. High recoveries (70–98%) and good reproducibility (relative standard deviation between 3 and 12%) were obtained using PS-DVB disks, which can be recommended for the enrichment of samples with low concentration of phenols (0.5 μg 1−1). For more concentrated samples (10 μg 1−1), the use of C18 cartridges was preferred because smaller solvent and sample volumes were used and the analysis time was reduced.

Analytical procedures for the determination of free and total sulfate and phosphate in glycosaminoglycans by high-performance liquid chromatography were studied. A column-switching method coupling high-performance size-exclusion chromatography (HPSEC) and ion chromatography (IC) is proposed for the determination of free anions. Good run-to-run and day-to-day precision values (RSD) of < 4.7% were obtained for both anions. Total anion contents were determined after wet acid hydrolysis with nitric acid-hydrogen peroxide (5 + 1) by single-column IC and ICP-AES elemental analysis in order to validate the results. Recoveries ranging from 94.6 to 99.0% for sulfate and from 80.8 to 94.0% for phosphate were obtained. Both HPSEC-IC and single-column IC methods were applied to the analysis of a low molecular mass heparin, a non-fractionated heparin and a chondroitin 4-sulfate. From the free and total sulfate determinations, the content of linked sulfur was calculated and ranged from 5.1 to 12.2% m/m.

Publisher Summary Phenolic compounds are ubiquitous in the environment. They occur as natural constituents and mediate in many industrial processes—for example, in the manufacture of plastics, dyes, drugs, and antioxidants. Phenols are also breakdown products from natural organic compounds, such as humic substances, lignins and tannins, which are widespread in the environment. The environmental half-lives of most chlorophenols are short, rarely as long as a month: once discharge ceases, levels drop rapidly due to bacterial breakdown. Apart from water problems, chlorophenols can be adsorbed into the soil. The adsorption and desorption of chlorophenols from soils depend on the number of chlorine substituents and also on their position on the phenolic ring. Pentachlorophenol (PCP) can be assimilated by humans through inhalation, skin penetration, and the digestive system, and may cause toxic damage to the liver and changes in the immunological system. Gas chromatography (GC) is extensively used for the analysis of phenolic compounds in water, sludges, and soil samples due to some advantages such as high separation efficiency, resolution, and sensitivity, as well as its rapidity of analysis.

A method based on ultra-high performance liquid chromatography (UHPLC) is proposed for the determination of chloramphenicol (CAP), its related compounds, thiamphenicol (TAP) and florfenicol (FF), and the polar metabolite florfenicol-amine (FFA), in animal-derived foods (chicken and pork meat, fish, prawns and honey). For the retention of FFA and its simultaneous analysis with the parent compounds a phenyl-hexyl column is proposed. A fast separation is achieved in less than 2 minutes using a methanol : acetic acid-ammonium acetate buffer (5 mM, pH 5) and gradient elution. Under these conditions, the FFA is retained at more than twice the dead volume, as recommended by the legislation. For the coupling with mass spectrometry, heated-electrospray (H-ESI) is used as ionisation source improving vaporization efficiency. To prevent interferences using selected-reaction monitoring (SRM) both quantitation and confirmation transitions were carefully selected. Two different sample treatments based on solid-phase extraction with mixed-mode cartridges for fish and meat products and hydrophilic-lipophilic-balanced cartridges for honey are proposed, providing limits of quantitation (LOQs) below μg kg(-1) level.