Elucidating the removal of organic micropollutants on biological ion exchange resins.

Biological ion exchange (BIEX) refers to operating ion exchange (IX) filters with infrequent regeneration to favor the microbial growth on resin surface and thereby contribute to the removal of organic matter through biodegradation. However, the extent of biodegradation on BIEX resins is still debatable due to the difficulty in discriminating between biodegradation and IX. The objective of the present study was to evaluate the performance of BIEX resins for the removal of organic micropollutants and thereby validate the occurrence of biodegradation.

Performance of conventional drinking water treatment following dispersant remediation of an oil spill in surface water.

Physical remediation such as the use of booms has been applied for most oil-spill cleanup activities in surface water. The application of dispersants has been controversial primarily due to the unknown impacts on drinking water sources. This study investigated changes in surface water quality following dispersant application to crude oil spills and the subsequent impact on the efficiency of ballasted flocculation, a physicochemical treatment process applied in many drinking water treatment plants (DWTP).

A data-independent acquisition approach based on HRMS to explore the biodegradation process of organic micropollutants involved in a biological ion-exchange drinking water filter.

Drinking water producers continuously develop innovative treatment processes to effectively remove organic micropollutants from raw water. Biological ion-exchange (BIEX) water treatment is one of these new techniques under development and showing great potential. In order to investigate if biodegradation is highly involved in such a removal technique, cultures were prepared with microorganisms sampled on the resins of a BIEX filter.

Evaluation of ELISA-based method for total anabaenopeptins determination and comparative analysis with on-line SPE-UHPLC-HRMS in freshwater cyanobacterial blooms.

Anabaenopeptins (APs) are bioactive cyanopeptides of emerging concern produced by cyanobacteria. The research for analytical development has recently gained in importance due to their abundance in toxic cyanobacterial blooms. A new commercial enzyme-linked immunosorbent assay kit for the determination of total APs (AP ELISA) has been released promising a rapid response with good cost efficiency for the routine monitoring of uncommon cyanopeptides.

A Data-Independent Methodology for the Structural Characterization of Microcystins and Anabaenopeptins Leading to the Identification of Four New Congeners.

Toxin-producing cyanobacteria are responsible for the presence of hundreds of bioactive compounds in aquatic environments undergoing increasing eutrophication. The identification of cyanotoxins is still emerging, due to the great diversity of potential congeners, yet high-resolution mass spectrometry (HRMS) has the potential to deepen this knowledge in aquatic environments. In this study, high-throughput and sensitive on-line solid-phase extraction ultra-high performance liquid chromatography (SPE-UHPLC) coupled to HRMS was applied to a data-independent acquisition (DIA) workflow for the suspect screening of cyanopeptides, including microcystin and anabaenopeptin toxin classes.

Detection of Cyanotoxins in Algae Dietary Supplements.

Algae dietary supplements are marketed worldwide as natural health products. Although their proprieties have been claimed as beneficial to improve overall health, there have been several previous reports of contamination by cyanotoxins. These products generally contain non-toxic cyanobacteria, but the methods of cultivation in natural waters without appropriate quality controls allow contamination by toxin producer species present in the natural environment.

Fractionation and analysis of veterinary antibiotics and their related degradation products in agricultural soils and drainage waters following swine manure amendment.

The fate of antimicrobial active compound residues in the environment, and especially antibiotics used in swine husbandry are of particular interest for their potential toxicity and contribution to antibiotic resistance. The presence of relatively high concentrations of bioactive compounds has been reported in agricultural areas but few information is available on their degradation products. Veterinary antibiotics reach terrestrial environments through many routes, including application of swine manure to soils.

Development of a suspect and non-target screening approach to detect veterinary antibiotic residues in a complex biological matrix using liquid chromatography/high-resolution mass spectrometry.

Rationale: Swine manure can contain a wide range of veterinary antibiotics, which could enter the environment via manure spreading on agricultural fields. A suspect and non-target screening method was applied to swine manure samples to attempt to identify veterinary antibiotics and pharmaceutical compounds for a future targeted analysis method.

Methods: A combination of suspect and non-target screening method was developed to identify various veterinary antibiotic families using liquid chromatography coupled with high-resolution mass spectrometry (LC/HRMS).

Total Analysis of Microcystins in Fish Tissue Using Laser Thermal Desorption-Atmospheric Pressure Chemical Ionization-High-Resolution Mass Spectrometry (LDTD-APCI-HRMS).

Microcystins (MCs) are cyanobacterial toxins encountered in aquatic environments worldwide. Over 100 MC variants have been identified and have the capacity to covalently bind to animal tissue. This study presents a new approach for cell-bound and free microcystin analysis in fish tissue using sodium hydroxide as a digestion agent and Lemieux oxidation to obtain the 2-methyl-3-methoxy-4-phenylbutyric acid (MMPB) moiety, common to all microcystin congeners.

Determination of BMAA and three alkaloid cyanotoxins in lake water using dansyl chloride derivatization and high-resolution mass spectrometry.

A new analytical method was developed for the detection of alkaloid cyanotoxins in harmful algal blooms. The detection of the nonproteinogenic amino acid β-N-methylamino-L-alanine (BMAA) and two of its conformation isomers, 2,4-diaminobutyric acid (DAB) and N-(2-aminoethyl) glycine (AEG), as well as three alkaloid cyanotoxins, anatoxin-a (ANA-a), cylindrospermopsin (CYN), and saxitoxin (STX), is presented. The use of a chemical derivatization with dansyl chloride (DNS) allows easier separation with reversed phase liquid chromatography.

High resolution/accurate mass (HRMS) detection of anatoxin-a in lake water using LDTD-APCI coupled to a Q-Exactive mass spectrometer.

A new innovative analytical method combining ultra-fast analysis time with high resolution/accurate mass detection was developed to eliminate the misidentification of anatoxin-a (ANA-a), a cyanobacterial toxin, from the natural amino acid phenylalanine (PHE). This was achieved by using the laser diode thermal desorption-atmospheric pressure chemical ionization (LDTD-APCI) coupled to the Q-Exactive, a high resolution/accurate mass spectrometer (HRMS). This novel combination, the LDTD-APCI-HRMS, allowed for an ultra-fast analysis time (<15 s/sample).

Quantitative performance of liquid chromatography coupled to Q-Exactive high resolution mass spectrometry (HRMS) for the analysis of tetracyclines in a complex matrix.

The presence of antibiotics in the environment is of increased interest and, as modern mass spectrometers become more efficient, we are increasingly aware of traces of pharmaceuticals appearing in a wide range of environmental and biological matrices. The Q-Exactive mass spectrometer is part of these innovative hybrid high-resolution mass spectrometers (HRMS) which is often associated with peptide sequencing or metabolomics but with a limited number of studies focusing on its application to the quantification of small molecules in environmental and biological matrices. It combines the high resolving power (RP) performance of the Orbitrap with the high performance selectivity of the quadrupole.

Analysis of trimethoprim, lincomycin, sulfadoxin and tylosin in swine manure using laser diode thermal desorption-atmospheric pressure chemical ionization-tandem mass spectrometry.

A new extraction method coupled to a high throughput sample analysis technique was developed for the determination of four veterinary antibiotics. The analytes belong to different groups of antibiotics such as chemotherapeutics, sulfonamides, lincosamides and macrolides. Trimethoprim (TMP), sulfadoxin (SFX), lincomycin (LCM) and tylosin (TYL) were extracted from lyophilized manure using a sonication extraction.

Ultra-fast analysis of anatoxin-A using laser diode thermal desorption-atmospheric pressure chemical ionization-tandem mass spectrometry: validation and resolution from phenylalanine.

A novel approach for the analysis of the cyanobacterial toxin, anatoxin-a (ANA-a), in an environmentally relevant matrix, using laser diode thermal desorption-atmospheric pressure chemical ionization-tandem mass spectrometry (LDTD-APCI-MS/MS) is presented. The ultra-fast analysis time (15 s/sample) provided by the LDTD-APCI interface is strengthened by its ability to remove interference from phenylalanine (PHE), an isobaric interference in ANA-a analysis by MS/MS. Thus the LDTD-APCI interface avoids the time consuming steps of derivatization, chromatographic separation or solid-phase extraction prior to analysis.