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1.
Anal Bioanal Chem ; 409(21): 4959-4969, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28634756

ABSTRACT

Microcystins are cyclic heptapeptide hepatotoxins produced by cyanobacteria in freshwater. Sample preparation for the analysis of these cyanotoxins in water from algal blooms can take up to several days due to the matrix complexity and the low detection limits required to comply with current legislation. Moreover, there is a large number of unknown microcystins that could potentially exist in the environment resulting from different amino acid substitutions into the microcystin skeletal structure. To tackle these problems, the present study involved the development of a high throughput method based on on-line solid phase extraction coupled to liquid chromatography that could provide quantitative results for 12 microcystin variants (LR, YR, RR, HtyR, HilR, WR, LW, LA, LF, LY, Dha7-LR, and Dha7-RR) and anatoxin-A in less than 3 h with detection limits between 0.004 and 0.01 µg L-1 and expanded uncertainty between 4 and 14%. Data-dependent acquisition was employed for the non-targeted analysis of these cyanotoxins. Filtering the data based on structure diagnostic fragments, two unknown microcystin variants not previously reported in the literature were detected. The structures Leu1-microcystin-Met(O)R and Leu1-microcystin-LY were fully characterized by accurate mass measurement, collision-induced dissociation, and fragmentation prediction software.


Subject(s)
Chromatography, Liquid/methods , Mass Spectrometry/methods , Microcystins/analysis , Solid Phase Extraction/methods , Tropanes/analysis , Cyanobacteria Toxins , Limit of Detection
2.
Waste Manag ; 26(9): 1005-16, 2006.
Article in English | MEDLINE | ID: mdl-16307874

ABSTRACT

Organic solvent and water extracts of fly ash from a Milan (Italy) municipal solid waste incinerator (MSWI) were analyzed by large volume injection-gas chromatography-mass spectrometry (LVI-GC-MS) with programmable temperature vaporizer (PTV). Using injection volumes of 10-100 microl, typically over a hundred compounds were detected in organic solvent extracts and ca. 35% of them could be tentatively identified from their electron impact ionization mass spectra. A protocol for the determination of the maximum amount of a potential environmental pollutant available for leaching (availability test) was developed for four selected target compounds: pentachlorobenzene (PeCB), hexachlorobenzene (HxCB), o-terphenyl (o-TPH) and m-terphenyl (m-TPH). Key parameters, extraction time and liquid-to-solid ratio (L/S), were studied in more detail. Recoveries of PeCB, HxCB and o-TPH spiked into the fly ash samples at two concentration levels ranged from 38% to 53% for freshly spiked and from 14% to 40% for 40-day aged fly ash. Recoveries of m-TPH were 8% to 11% from freshly spiked and less than 3% from aged spiked fly ash. The native amounts in Milan MSWI fly ash, determined in an interlaboratory exercise using the developed protocol, were 31 ng/g PeCB, 34 ng/g HxCB, 72 ng/g o-TPH and 4.4 ng/g m-TPH. A separate methodology was developed for the determination of compounds extracted from fly ash by water (leaching test). Following 8-h sonication at L/S 20, the leached amounts of PeCB, HxCB and o-TPH were 1.1, 3.1 and 6.0 ng/g fly ash, respectively.


Subject(s)
Gas Chromatography-Mass Spectrometry/methods , Incineration , Organic Chemicals/analysis , Refuse Disposal/instrumentation , Carbon , Coal Ash , Particulate Matter , Refuse Disposal/methods
3.
Biosens Bioelectron ; 20(8): 1499-508, 2005 Feb 15.
Article in English | MEDLINE | ID: mdl-15626603

ABSTRACT

A novel analytical system AWACSS (automated water analyser computer-supported system) based on immunochemical technology has been developed that can measure several organic pollutants at low nanogram per litre level in a single few-minutes analysis without any prior sample pre-concentration nor pre-treatment steps. Having in mind actual needs of water-sector managers related to the implementation of the Drinking Water Directive (DWD) (98/83/EC, 1998) and Water Framework Directive WFD (2000/60/EC, 2000), drinking, ground, surface, and waste waters were major media used for the evaluation of the system performance. The instrument was equipped with remote control and surveillance facilities. The system's software allows for the internet-based networking between the measurement and control stations, global management, trend analysis, and early-warning applications. The experience of water laboratories has been utilised at the design of the instrument's hardware and software in order to make the system rugged and user-friendly. Several market surveys were conducted during the project to assess the applicability of the final system. A web-based AWACSS database was created for automated evaluation and storage of the obtained data in a format compatible with major databases of environmental organic pollutants in Europe. This first part article gives the reader an overview of the aims and scope of the AWACSS project as well as details about basic technology, immunoassays, software, and networking developed and utilised within the research project. The second part article reports on the system performance, first real sample measurements, and an international collaborative trial (inter-laboratory tests) to compare the biosensor with conventional anayltical methods.


Subject(s)
Biosensing Techniques/instrumentation , Environmental Monitoring/instrumentation , Immunoassay/instrumentation , Internet , Organic Chemicals/analysis , Software , Water Pollutants, Chemical/analysis , Algorithms , Biosensing Techniques/methods , Biotechnology/instrumentation , Biotechnology/methods , Database Management Systems/instrumentation , Environmental Monitoring/methods , Equipment Design , Equipment Failure Analysis , Immunoassay/methods , Information Storage and Retrieval/methods , Microchemistry/instrumentation , Microchemistry/methods , Microcomputers , Microfluidic Analytical Techniques/instrumentation , Microfluidic Analytical Techniques/methods , Software Design , User-Computer Interface
4.
Biosens Bioelectron ; 20(8): 1509-19, 2005 Feb 15.
Article in English | MEDLINE | ID: mdl-15626604

ABSTRACT

A novel analytical system AWACSS (Automated Water Analyser Computer Supported System) based on immunochemical technology has been evaluated that can measure several organic pollutants at low nanogram per litre level in a single few-minutes analysis without any prior sample pre-concentration or pre-treatment steps. Having in mind actual needs of water-sector managers related to the implementation of the Drinking Water Directive (DWD) [98/83/EC, 1998. Council Directive (98/83/EC) of 3 November 1998 relating to the quality of water intended for human consumption. Off. J. Eur. Commun. L330, 32-54] and Water Framework Directive (WFD) [2000/60/EC, 2000. Directive 2000/60/EC of the European Parliament and of the Council of 23 October 2000 establishing a framework for Community action in the field of water policy. Off. J. Eur. Commun. L327, 1-72], drinking, ground, surface, and waste waters were major media used for the evaluation of the system performance. The first part article gave the reader an overview of the aims and scope of the AWACSS project as well as details about basic technology, immunoassays, software, and networking developed and utilised within the research project. The second part reports on the system performance, first real sample measurements, and an international collaborative trial (inter-laboratory tests) to compare the biosensor with conventional anayltical methods. The systems' capability for analysing a wide range of environmental organic micro-pollutants, such as modern pesticides, endocrine disrupting compounds and pharmaceuticals in surface, ground, drinking and waste water is shown. In addition, a protocol using reconstitution of extracts of solid samples, developed and applied for analysis of river sediments and food samples, is presented. Finally, the overall performance of the AWACSS system in comparison to the conventional analytical techniques, which included liquid and gas chromatographic systems with diode-array UV and mass spectrometric detectors, was successfully tested in an inter-laboratory collaborative trial among six project partners.


Subject(s)
Environmental Monitoring/instrumentation , Equipment Failure Analysis , Immunoassay/instrumentation , Internet , Organic Chemicals/analysis , Software , Water Pollutants, Chemical/analysis , Algorithms , Biosensing Techniques/instrumentation , Biosensing Techniques/methods , Biotechnology/instrumentation , Biotechnology/methods , Database Management Systems/instrumentation , Environmental Monitoring/methods , Equipment Design , Immunoassay/methods , Information Storage and Retrieval/methods , Microchemistry/instrumentation , Microchemistry/methods , Microcomputers , Microfluidic Analytical Techniques/instrumentation , Microfluidic Analytical Techniques/methods , Reproducibility of Results , Sensitivity and Specificity , Software Design , User-Computer Interface
5.
J Chromatogr Sci ; 42(10): 531-5, 2004.
Article in English | MEDLINE | ID: mdl-15768839

ABSTRACT

Large-volume injection utilizing programmable temperature vaporizer in solvent vent mode is combined with fast capillary gas chromatography and mass spectrometric detection. Optimized injection and chromatographic conditions made possible manual injection of a 20-microL ethyl acetate extract containing 15 organochlorine pesticides and their separation on a short, 0.1-mm-i.d. column in less than 8 min.

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