Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

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    We will mail you new results for this query: keywords==Liquid chromatography
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General Framing of Low-, Mid-, and High-Level Data Fusion With Examples in the Life Sciences
Smolinska, Agnieszka ; Engel, Jasper ; Szymanska, Ewa ; Buydens, Lutgarde ; Blanchet, Lionel - \ 2019
In: Data Fusion Methodology and Applications Elsevier Ltd, Academic Press (Data Handling in Science and Technology ) - ISBN 9780444639844 - p. 51 - 79.
Analytical technique - Data fusion - Gas chromatography–mass spectrometry - Kernel-based data fusion - Liquid chromatography - Microbiome data

The constant development of analytical techniques leads to an increase in the amount of information available to describe phenomena in life science. In parallel, the inherent complexity of life science makes it almost impossible to obtain a comprehensive description using only one technical modality. Therefore, it became very popular to combine several biological or technical platforms/modalities to obtain a better understanding of the underlying problems. Merging different types of measurements/platforms into a single analysis is, however, a complex topic. Combining various platforms into single analysis is defined as data fusion. We describe here different types of data fusion strategies: the well-established low-, mid-, and high-level data fusion and the more recently introduced sustainable mid-level data fusion and kernel-based data fusion. For each type, we provide a detailed description. To illustrate these various data fusion approaches, we rely on four real data sets, namely, exhaled breath data of patients with Crohn disease (CD) obtained by gas chromatography–mass spectrometry (GC-MS), 454 pyrosequencing microbiome data of patients with CD, and metabolic profiling of beer brands by GC-MS and positive and negative ion modes of liquid chromatography.

High resolution full scan liquid chromatography mass spectrometry comprehensive screening in sports antidoping urine analysis
Abushareeda, Wadha ; Vonaparti, Ariadni ; Saad, Khadija Al ; Almansoori, Moneera ; Meloug, Mbarka ; Saleh, Amal ; Aguilera, Rodrigo ; Angelis, Yiannis ; Horvatovich, Peter L. ; Lommen, Arjen ; Alsayrafi, Mohammed ; Georgakopoulos, Costas - \ 2018
Journal of Pharmaceutical and Biomedical Analysis 151 (2018). - ISSN 0731-7085 - p. 10 - 24.
Full scan high-resolution - Human urine - Liquid chromatography - Mass spectrometry - Small molecule prohibited substances - Sulfo-conjugate steroids
The aim of this paper is to present the development and validation of a high-resolution full scan (HR-FS) electrospray ionization (ESI) liquid chromatography coupled to quadrupole Orbitrap mass spectrometer (LC/Q/Orbitrap MS) platform for the screening of prohibited substances in human urine according to World Antidoping Agency (WADA) requirements. The method was also validated for quantitative analysis of six endogenous steroids (epitestosterone, testosterone, 5α-dihydrotestosterone, dehydroepiandrosterone, androsterone and etiocholanolone) in their intact sulfates form. The sample preparation comprised a combination of a hydrolyzed urine liquid–liquid extraction and the dilute & shoot addition of original urine in the extracted aliquot. The HR-FS MS acquisition mode with Polarity Switching was applied in combination of the Quadrupole-Orbitrap mass filter. The HR-FS acquisition of analytical signal, for known and unknown small molecules, allows the inclusion of all analytes detectable with LC–MS for antidoping investigations to identify the use of known or novel prohibited substances and metabolites after electronic data files’ reprocessing. The method has been validated to be fit-for-purpose for the antidoping analysis.
A global inter-laboratory study to assess acquisition modes for multi-compound confirmatory analysis of veterinary drugs using liquid chromatography coupled to triple quadrupole, time of flight and orbitrap mass spectrometry
Berendsen, Bjorn J.A. ; Meijer, Thijs ; Mol, Hans G.J. ; Ginkel, Leen van; Nielen, Michel W.F. - \ 2017
Analytica Chimica Acta 962 (2017). - ISSN 0003-2670 - p. 60 - 72.
Inter-laboratory study - Liquid chromatography - Mass spectrometry - Performance criteria - Veterinary drugs residue analysis

According to EU legislation a confirmatory method used for residue analysis should be able to confirm the identity of a compound beyond reasonable doubt. To provide an adequate instrumental set-up, Commission Decision 2002/657/EC introduced the concept of "identification points". A second aspect to assure unequivocal confirmation, is the establishment of ion ratio and retention time criteria. Currently, the gold standard for confirmatory analysis of most veterinary drug residues is liquid chromatography (LC) coupled to tandem mass spectrometry (MS/MS) in selected reaction monitoring (SRM) acquisition mode, isolating one precursor ion and monitoring two a priori selected product ions, yielding 4 identification points. We comprehensively evaluated the use of different low and high resolution LC-MS(/MS) techniques and acquisition modes with respect to the selectivity of 100 veterinary drugs in liver, muscle and urine extracts aiming to critically review the currently established identification points system. A comparison among MS/MS in SRM mode with high resolution mass spectrometry (HRMS) in full scan, all ion fragmentation and targeted MS/MS was made based on a unique inter-laboratory study, which comprises 21 laboratories from four different continents and equipment from all major vendors.In total 186 samples were analysed yielding results for 9282 analyte/matrix combinations. It was observed that the false positive rate approximately doubles if no ion ratio criterion is applied indicating that this criterion is important to prevent false positive results. Full scan HRMS analysis, only monitoring the molecular ion and allowing a ±5 ppm mass tolerance is, in general, less selective than low resolution MS/MS using SRM, and thus full scan alone is considered not sufficient for confirmatory analysis. Furthermore, even though the number of data on all ion fragmentation and targeted MS/MS at high resolution was limited, based on the data obtained, it was observed that the acquisition mode as well as the mass resolution needed, very much depend on the matrix and the compound itself. For complex matrix extracts and non-selective compounds (worst-case situation), only targeted MS/MS, monitoring the precursor ion and a single product ion in HR-MS using a maximum of ±5 ppm mass deviation, leads to comparable selectivity and false positive and negative rate as SRM monitoring two product ions in LR-MS. We conclude that the currently applied identification point system as established in commission decision 2002/657/EC should be revised with respect to the allocation of identification points.

Protocatechuic acid levels discriminate between organic and conventional wheat from Denmark
Weesepoel, Yannick ; Heenan, Samuel ; Boerrigter-Eenling, Rita ; Venderink, Tjerk ; Blokland, Marco ; Ruth, Saskia Van - \ 2016
Chimia 70 (2016)5. - ISSN 0009-4293 - p. 360 - 363.
Cereals - Food adulteration - Food fraud - Liquid chromatography - Phenolic acids - Wheat

Organic wheat retails at higher market prices than the conventionally grown counterparts. In view of fair competition and sustainable consumer confidence, the organic nature of organic wheat needs to be assured. Amongst other controls this requires analytical tests based on discriminating traits. In this paper, phenolic acids were examined by liquid chromatography analysis as biomarkers for discriminating between the two groups by means of a controlled grown full factorial design Danish wheat sample set. By combining baseline and retention-time correction pre-treatments and principal component analysis, discrimination between organic and conventional produce was found to be expressed in the first principal component (93%), whilst the second principal component accounted for the production year (4%). Upon examination of the loadings plot, a single chromatographic peak was found to account for a large part in the discrimination between the two wheat production systems. This was further underpinned by statistically significant differences found in concentrations between the organic and conventional production systems of this phenolic acid (ANOVA, P

Monolith immuno-affinity enrichment liquid chromatography tandem mass spectrometry for quantitative protein analysis of recombinant bovine somatotropin in serum
Smits, N.G.E. ; Blokland, M.H. ; Wubs, K.L. ; Nessen, M.A. ; Ginkel, L.A. van; Nielen, M.W.F. - \ 2015
Analytical and Bioanalytical Chemistry 407 (2015)20. - ISSN 1618-2642 - p. 6041 - 6050.
bST - Immuno-affinity enrichment - Liquid chromatography - Mass spectrometry - Monolith micro-column - Recombinant bovine somatotropin

The use of recombinant bovine somatotropin (rbST) to enhance milk production is approved in several countries, but it is prohibited in the European Union. According to EU legislation, it is necessary to confirm positive screening results prior to enforcement. Although adequate screening assays are available nowadays, development of liquid chromatography tandem mass spectrometry (LC-MS/MS) confirmatory methods to detect low levels of rbST is still a challenge. Here, we present a novel approach using immuno-affinity enrichment on monolithic micro-columns in combination with state-of-the-art ultra-high pressure LC-MS/MS (UHPLC-MS/MS) detection. The developed approach enables detection and confirmation of rbST in serum at a decision limit (CCα) concentration of 0.8 ng mL−1. Furthermore, the method is easy to handle, robust and reproducible. We successfully applied the confirmatory method to serum samples from rbST treated cows that were found suspect after immunoassay-based screening. The use of rbST could be confirmed over 1 week after treatment, and the developed method demonstrated the sensitivity needed for effective control. [Figure not available: see fulltext.]

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