TY  - JOUR
AB  - Non-targeted chemical analysis is a powerful tool for exploration of the unknown chemistry of complex matrices such as food, biological, geochemical, environmental and even extra-terrestrial samples. It allows researchers to ask open, unbiased questions about their system chemistry. Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR-MS) offers these options and has been widely used to study complex mixtures, with its unmatched mass resolution enabling direct infusion methods and eliminating the challenges of chromatographic alignment in large-scale longitudinal projects. In this article, we demonstrate the use of FT-ICR-MS for generating a dataset for hundreds of complex samples with diverse chemistries over a period of 6 years and 32 batches, allowing confident comparison of data between samples from different batches. The resulting chemical database will be continuously expanded in future and retrospectively interrogated to test new hypotheses utilizing data of past projects and new knowledge of coming projects. We discuss the experimental setup and how other researchers could apply the same approaches, which is relevant for wide ranging applications and research fields.
AU  - Woodward, S.E.*
AU  - Pieczonka, S.
AU  - Hertzog, J.
AU  - Haydock, R.*
AU  - Thomas, M.J.*
AU  - Roullier-Gall, C.
AU  - O'Flynn, C.*
AU  - Uhl, J.
AU  - Rychlik, M.*
AU  - Schmitt-Kopplin, P.
AU  - Marshall, J.W.*
C1  - 73011
C2  - 56892
CY  - Radarweg 29, 1043 Nx Amsterdam, Netherlands
TI  - Continuum of non-targeted data for long term study of complex samples generated by direct infusion ultra-high resolution mass spectrometry.
JO  - Talanta
VL  - 286
PB  - Elsevier
PY  - 2025
SN  - 0039-9140
ER  - 

TY  - JOUR
AB  - Proton relaxation in model and real wines is investigated for the first time by fast field cycling NMR relaxometry. The relaxation mechanism unambiguously originates form proton interaction with paramagnetic ions naturally present in wines. Profiles of a white Chardonnay wine from Burgundy, a red Medoc, and model wines are well reproduced by Solomon-Bloembergen-Morgan equations. Relaxation is primarily governed by interactions with Mn2+. A straightforward model-independent quantification of the manganese ion concentration (down to few tens of mu g/L) is proposed.
AU  - Bodart, P.R.*
AU  - Rachocki, A.*
AU  - Tritt-Goc, J.*
AU  - Michalke, B.
AU  - Schmitt-Kopplin, P.
AU  - Karbowiak, T.*
AU  - Gougeon, R.D.*
C1  - 57628
C2  - 47842
CY  - Radarweg 29, 1043 Nx Amsterdam, Netherlands
TI  - Quantification of manganous ions in wine by NMR relaxometry.
JO  - Talanta
VL  - 209
PB  - Elsevier
PY  - 2020
SN  - 0039-9140
ER  - 

TY  - JOUR
AB  - Comprehensive chemical investigation of non-volatile complex mixtures, without extensive sample pretreatment, remains challenging due to the high number of constituents with different chemical properties. In past years, direct high-resolution mass spectrometry established itself as powerful technique for the detailed molecular description of ultra-complex mixtures, but was mainly used with atmospheric pressure ionization. In this study, we present a direct inlet approach with vacuum ionization and high-resolution time-of-flight mass spectrometry. Exemplary, the non-volatile fractions of crude oil were directly inserted into the ion source and volatilized under reduced pressure conditions. An applied temperature gradient enabled thermal pre-separation, according to volatility, prior to electron ionization and mass spectrometric detection. With exact mass information, peaks were assigned to elemental compositions and grouped into component classes. Moreover, the application of supervised and unsupervised statistical tools allowed differentiation of the samples on a molecular level and the identification and attribution of significant chemical features.
AU  - Käfer, U.
AU  - Gröger, T.M.
AU  - Rüger, C.P.*
AU  - Czech, H.
AU  - Saraji-Bozorgzad, M.R.*
AU  - Wilharm, T.*
AU  - Zimmermann, R.
C1  - 56038
C2  - 46770
CY  - Po Box 211, 1000 Ae Amsterdam, Netherlands
SP  - 308-316
TI  - Direct inlet probe - High-resolution time-of-flight mass spectrometry as fast technique for the chemical description of complex high-boiling samples.
JO  - Talanta
VL  - 202
PB  - Elsevier Science Bv
PY  - 2019
SN  - 0039-9140
ER  - 

TY  - JOUR
AB  - Volatile profiles of 63 black and 38 green teas from different countries were analysed with Proton Transfer Reaction-Time of Flight-Mass Spectrometry (PTR-ToF-MS) both for tea leaves and tea infusion. The headspace volatile fingerprints were collected and the tea classes and geographical origins were tracked with pattern recognition techniques. The high mass resolution achieved by ToF mass analyser provided determination of sum formula and tentative identifications of the mass peaks. The results provided successful separation of the black and green teas based on their headspace volatile emissions both from the dry tea leaves and their infusions. The volatile fingerprints were then used to build different classification models for discrimination of black and green teas according to their geographical origins. Two different cross validation methods were applied and their effectiveness for origin discrimination was discussed. The classification models showed a separation of black and green teas according to geographical origins the errors being mostly between neighbouring countries.
AU  - Yener, S.*
AU  - Sánchez-López, J.A.*
AU  - Granitto, P.M.*
AU  - Cappellin, L.*
AU  - Märk, T.D.*
AU  - Zimmermann, R.
AU  - Bonn, G.K.*
AU  - Yeretzian, C.*
AU  - Biasioli, F.*
C1  - 47907
C2  - 39747
CY  - Amsterdam
SP  - 45-53
TI  - Rapid and direct volatile compound profiling of black and green teas (Camellia sinensis) from different countries with PTR-ToF-MS.
JO  - Talanta
VL  - 152
PB  - Elsevier Science Bv
PY  - 2016
SN  - 0039-9140
ER  - 

TY  - JOUR
AB  - Nuclear fuel particles of Chernobyl origin are carriers of increased radioactivity (hot particles) and are still present in the atmosphere of the Chernobyl exclusion zone. Workers in the zone may inhale these particles, which makes assessment necessary. The residence time in the lungs and the transfer in the blood of the inhaled radionuclides are crucial for inhalation dose assessment. Therefore, the dissolution of several kinds of nuclear fuel particles from air filters sampled in the Chernobyl exclusion zone was studied. For this purpose filter fragments with hot particles were submersed in simulated lung fluids (SLFs). The activities of the radionuclides 137Cs, 90Sr, 239+240Pu and 241Am were measured in the SLF and in the residuum of the fragments by radiometric methods after chemical treatment. Soluble fractions as well as dissolution rates of the nuclides were determined. The influence of the genesis of the hot particles, represented by the 137Cs/239+240Pu ratio, on the availability of 137Cs was demonstrated, whereas the dissolution of 90Sr, 239+240Pu and 241Am proved to be independent of genesis. No difference in the dissolution of 137Cs and 239+240Pu was observed for the two applied types of SLF. Increased solubility was found for smaller hot particles. A two-component exponential model was used to describe the dissolution of the nuclides as a function of time. The results were applied for determining individual inhalation dose coefficients for the workers at the Chernobyl construction site. Greater dose coefficients for the respiratory tract and smaller coefficients for the other organs were calculated (compared to ICRP default values). The effective doses were in general lower for the considered radionuclides, for 241Am even by one order of magnitude.
AU  - Garger, E.K.*
AU  - Meisenberg, O.
AU  - Odintsov, O.*
AU  - Shynkarenko, V.*
AU  - Tschiersch, J.
C1  - 24505
C2  - 31565
SP  - 40-46
TI  - Solubility of hot fuel particles from Chernobyl - influencing parameters for individual radiation dose calculations.
JO  - Talanta
VL  - 115
PB  - Elsevier Science
PY  - 2013
SN  - 0039-9140
ER  - 

TY  - JOUR
AB  - In the previous reports about cognitive dysfunction, cerebellum was thought to be a less affected tissue by genetic or environmental alterations in comparison to other tissues in the brain including hippocampus under the same conditions. In this work, we investigated two types of metabolomic alterations inside the cerebellum tissue. The first one addressed the differences in the metabolomics profiles between Transgenic (Tg) CRND8 of Alzheimer's disease mice and non-transgenic (non-Tg) littermates. The second one addressed the metabolic differences between wild type mice exposed to 2,3,7,8-tetrachlorodibenzo-p- dioxin (TCDD) and wild type mice which are not exposed to this toxic compound. For these two investigations, ultrahigh resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR/MS) was implemented. As a result, the significant changes of each comparison were tentatively annotated by the high mass accuracy generated from the measurements in the negative ion mode. The biosynthesis of amino acids was also enhanced pronouncedly, and perturbation of purine metabolism was also observed in Tg mice compared to non-Tg littermates. In another animal model, the reduced levels of amino acids were found whereas the intermediate levels in purine metabolism and fatty acids including fatty acid conjugated metabolites were elevated in cerebellar tissues of mice exposed to TCDD compared to control group. Collectively, it was demonstrated that FT-ICR/MS was a powerful tool for interpretation of the elemental compositions of the peaks, revealing that the metabolic perturbations in cerebellar tissues of mice were induced by either genetic manipulation or environmental factor. Therefore, the non-targeted approach, alternatively, provides various metabolic phenotypes for the systems-level mirror of the complex etiology of neurotoxicity in the cerebellum.
AU  - Lin, S.*
AU  - Kanawati, B.
AU  - Liu, L.*
AU  - Witting, M.
AU  - Li, M.*
AU  - Huang, J.*
AU  - Schmitt-Kopplin, P.
AU  - Cai, Z.*
C1  - 28166
C2  - 32979
SP  - 45-53
TI  - Ultrahigh resolution mass spectrometry-based metabolic characterization reveals cerebellum as a disturbed region in two animal models.
JO  - Talanta
VL  - 118
PB  - Elsevier Science
PY  - 2013
SN  - 0039-9140
ER  - 

TY  - JOUR
AB  - Enzyme linked immunosorbent assay (ELISA) kit is a versatile, cheap and relatively available tool that can be used in remote areas. In this study, performance of ELISA kit was evaluated in terms of accuracy, recovery, precision, sensitivity, cross reactivity and matrix interference for pesticide residue determination in water and sediment samples. This method was compared with high performance liquid chromatography (HPLC) which is not a commonly available analytical technique for chlorpyrifos ethyl residue analysis in developing countries. The ELISA kit had limits of detection (LOD) of 0.37 μg L-1 and 0.42 μg Kg-1 dry weight (dw), for chlorpyrifos ethyl in water and sediment samples, respectively using deionized water and a control sediment sample. Mean percentage recoveries and coefficients of variation (CV) for ELISA kit varied from 96.0±5.8% to 108.0±3.4% for water and sediment samples. Comparison between ELISA and HPLC analysis results using water and sediment samples from Lake Naivasha showed no significant difference in results (p≤0.05). Strong correlations (r 2=0.9878 water samples and r1=0.9670, p<0.0001 for sediment samples, n=48) were reported between the methods for the two samples analyzed. Bland-Altman bias plot analysis showed that the two methods were in agreement within 95% confidence interval of limits -2.9 to 3.8 and -2.2 to 3.6 for water and sediment, respectively. Given the high sensitivity reported and the obtained acceptable limits of coefficient of variation and percentage recovery, ELISA appears to be a suitable rapid analytical tool in analysis of chlorpyrifos ethyl in water and sediment samples. Results demonstrate comparability to HPLC and could complement conventional tools in regular monitoring program particularly in developing countries. This will hasten results delivery for ecological risk assessment and timely execution of mitigation measures.
AU  - Otieno, P.O.
AU  - Owuor, P.O.*
AU  - Lalah, J.O.*
AU  - Pfister, G.
AU  - Schramm, K.-W.
C1  - 27939
C2  - 32868
SP  - 250-257
TI  - Comparative evaluation of ELISA kit and HPLC DAD for the determination of chlorpyrifos ethyl residues in water and sediments.
JO  - Talanta
VL  - 117
PB  - Elsevier Science
PY  - 2013
SN  - 0039-9140
ER  - 

TY  - JOUR
AB  - Parallel computing was tested regarding its ability to speed up chemometric operations for data analysis. A set of metabolic samples from a second hand smoke (SHS) experiment was analyzed with comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry (GC×GC-TOFMS). Data was further preprocessed and analyzed. The preprocessing step comprises background correction, smoothing and alignment of the chromatographic signal. Data analysis was performed by applying t-test and partial least squares projection to latent structures discriminant analysis (PLS-DA). The optimization of the algorithm for parallel computing led to a substantial increase in performance. Metabolic fingerprinting showed a discrimination of the samples and indicates a metabolic effect of SHS.
AU  - Gröger, T.M.
AU  - Zimmermann, R.
C1  - 4838
C2  - 28658
SP  - 1289-1294
TI  - Application of parallel computing to speed up chemometrics for GC×GC-TOFMS based metabolic fingerprinting.
JO  - Talanta
VL  - 83
IS  - 4
PB  - Elsevier
PY  - 2011
SN  - 0039-9140
ER  - 

TY  - JOUR
AB  - Metabolomics is the downstream of systems biology and has drawn significant interest for studying the metabolic networks from cells to organisms. To profile the metabolites in two different cell lines (A549 and AGS) infected with influenza A virus, gas chromatography coupled with mass spectrometry (GC/MS) was employed. Some differentiating metabolites in the cell lines were tentatively identified using reference library, interpreted and visualized by applying principal components analysis (PCA) and cluster heat map. Consequently, metabolic flux profiling allowed the differentiation of fatty acid biosynthesis and cholesterol metabolism during viral replication in the cell lines. The change in fatty acid turnover was also observed. Metabolomics investigation also revealed the different responses between A549 and AGS cell lines to the virus infection. From the pattern recognition results, AGS cell line might be more susceptible to influenza A virus. Regarding the fact that AGS is a poorly differentiated gastric adenocarcinoma cell line whereas A549 is a relatively differentiated lung tumor one, it is speculated that viral replication might be associated with the cell differentiations.
AU  - Lin, S.*
AU  - Liu, N.*
AU  - Yang, Z.*
AU  - Song, W.*
AU  - Wang, P.*
AU  - Chen, H.*
AU  - Lucio, M.
AU  - Schmitt-Kopplin, P.
AU  - Chen, G.*
AU  - Cai, Z.*
C1  - 3405
C2  - 27978
SP  - 262-268
TI  - GC/MS-based metabolomics reveals fatty acid biosynthesis and cholesterol metabolism in cell lines infected with influenza A virus.
JO  - Talanta
VL  - 83
IS  - 1
PB  - Elsevier
PY  - 2010
SN  - 0039-9140
ER  - 

TY  - JOUR
AB  - Despite recent advances in treatment, mantle cell lymphoma (MCL) still represents a disease with dismal prognosis due to its progressive clinical course, high rate of therapy refractory cases and frequent relapses. During recent years, the proteasome inhibitor bortezomib and enzastaurin, an inhibitor of protein kinase c have been explored in MCL. In relapsed disease enzastaurin achieved disease stabilization in a subset of patients. Bortezomib in relapsed and refractory MCL achieves response rates of 30-40%. To identify signal pathways and manifold interactions regulating cellular response to molecular targeted approaches several high throughput screening methods were applied. A combined network analysis of the identified target molecules based on both RNA array expression data and a survey of cellular protein levels resulted in a unified interaction network more comprehensive (bortezomib: 394 and enzastaurin: 174 molecules) than the networks of the individual screening techniques (329/44 and 117/36 molecules respectively). Interestingly, although none of the target molecules were matched in both RNA-expression and protein level analysis they were mapped nonetheless to common pathways. Additionally, the ranking of identified pathways allowed an improved characterization of the observed induction of cell apoptosis.
AU  - Weinkauf, M.
AU  - Hutter, G.
AU  - Zimmermann, Y.
AU  - Hartmann, E.*
AU  - Rosenwald, A.*
AU  - Dreyling, M.
C1  - 6063
C2  - 27809
SP  - 1539-1544
TI  - Combined RNA-expression and 2D-PAGE-screening identifies comprehensive interaction networks affected after bortezomib or enzastaurin exposure of mantle cell lymphoma.
JO  - Talanta
VL  - 80
IS  - 4
PB  - Elsevier
PY  - 2010
SN  - 0039-9140
ER  - 

TY  - JOUR
AU  - Krämer, P.M.
AU  - Franke, A.
AU  - Zherdev, A.V.*
AU  - Yazynina, E.V.*
AU  - Dzantiev, B.B.*
C1  - 3351
C2  - 22109
SP  - 324-330
TI  - Comparison of two express immunotechniques with polyelectrolyte carriers, ELISA and FIIAA, for the analyses of atrazine.
JO  - Talanta
VL  - 65
PY  - 2005
SN  - 0039-9140
ER  - 

TY  - JOUR
AB  - The binding by peat of Ca(II), Cd(II), Zn(II), Cu(II) and Pb(II) present at trace-level concentrations in 0.0010, 0.010 and 0.10M sodium chloride, has been studied as a function of the degree of neutralization of the soil organic acid. The theoretically-based method used to express the complexation equilibria requires values for the concentrations of the several mobile counter-ions in the peat phase [M(II), H+ and Na+] and permits estimation of the nature of the complexed species formed in the peat as well as of reasonable values for the formation constants of the species formed. The values of the formation constants thus obtained are independent of the ionic strength of the equilibrating solution, as they should be. This result was unattainable with the earlier methods of computation used for studying these equilibria. The species formed are Ca(II)A+.HA and M(II)A+, where M(II) represents Cd(II), Zn(II), Cu(II) and Pb(II).
AU  - Marinsky, J.A.
AU  - Wolf, A.
AU  - Bunzl, K.W.
C1  - 41177
C2  - 38152
SP  - 461-468
TI  - The binding of trace amounts of lead(II), copper(II), cadmium(II), zinc(II) and calcium(II) to soil organic matter.
JO  - Talanta
VL  - 27
IS  - 6
PY  - 1980
SN  - 0039-9140
ER  -