Review
Chemistry, Analytical
Pierre-Hugues Stefanuto, Agnieszka Smolinska, Jean-Francois Focant
Summary: GCxGC-MS, as a mature technique, can be used for large-scale studies, but the challenges now lie in data management, requiring powerful chemometric tools. This review discusses recent advances in specific chemometrics for GCxGC-MS and details critical steps in data preprocessing, feature selection, model building, and validation.
TRAC-TRENDS IN ANALYTICAL CHEMISTRY
(2021)
Review
Food Science & Technology
Ana M. Jimenez-Carvelo, Luis Cuadros-Rodriguez
Summary: Foodomics aims to investigate the effects of food on health by collecting and analyzing data using data mining methods, often implemented on specific platforms due to researchers' lack of experience. This paper provides an overview of the latest research advances in data analysis processes in untargeted approaches, mainly using analytical techniques such as NMR, chromatography-MS, and 2D chromatography, while emphasizing the gaps that still need to be filled in the use of data mining methods. Additionally, it explains and discusses the terminology used in this field.
CURRENT OPINION IN FOOD SCIENCE
(2021)
Review
Chemistry, Multidisciplinary
Hadi Parastar, Roma Tauler
Summary: This Review summarizes the analysis of big (bio)chemical data using multivariate chemometric methods and discusses the challenges faced by analytical research. It emphasizes the potential of chemometric methods in solving BBCD problems in chromatographic, spectroscopic, and hyperspectral imaging measurements, with applications to omics sciences. The review provides insights on addressing analysis of BBCD, obtaining reliable qualitative and quantitative results. It discusses the importance of big data in (bio)chemistry, presents analytical tools for generating BBCD, and the theoretical background and limitations of chemometric methods when applied to BBCD. The review highlights the importance of chemometric methods in analyzing BBCD in different chemical disciplines with examples.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Review
Chemistry, Analytical
Puneet Mishra, Jean-Michel Roger, Delphine Jouan-Rimbaud-Bouveresse, Alessandra Biancolillo, Federico Marini, Alison Nordon, Douglas N. Rutledge
Summary: This review provides a brief overview of popular multi-block data analysis methods, including their concepts, applications, advantages and disadvantages, as well as software resources, emphasizing their importance in the field of chemometrics.
TRAC-TRENDS IN ANALYTICAL CHEMISTRY
(2021)
Article
Automation & Control Systems
Clara Perez-Rafols, Nuria Serrano, Jose Manuel Diaz-Cruz
Summary: A data fusion approach combining chromatographic and spectroscopic profiles was proposed to discriminate and classify soothing herbs. The proposed fusion approach outperformed the individual analytical techniques in terms of clusterization ability.
CHEMOMETRICS AND INTELLIGENT LABORATORY SYSTEMS
(2023)
Article
Chemistry, Analytical
Yu Wang, Bing Xia, Shunyan Deng, Ye Ye, Yan Zhou
Summary: The study introduces a new mass spectrometry imaging method that involves imprinting chemicals on a two-dimensional string plane for large sample analysis, demonstrating the ability to reconstruct 2D MSI images through data processing.
ANALYTICAL CHEMISTRY
(2022)
Article
Chemistry, Analytical
Stef R. A. Molenaar, Wouter C. Knol, Bob W. J. Pirok, Ron A. H. Peters
Summary: Information about the number-average copolymer sequence length can be obtained through pyrolysis-gas chromatography (Py-GC) by comparing the ratios of formed oligomers. However, the formation constants of the oligomers and their detection efficiency are not constant, leading to unreliable peak ratios in the chromatogram. To address this, an algorithm is introduced to improve the accuracy of copolymer sequence from chromatograms with unrepresentative peak areas. The algorithm even works when oligomer data is missing.
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
(2023)
Article
Automation & Control Systems
Bahram Hemmateenejad, Mohammad Mahdi Bordbar, Zahra Shojaeifard
Summary: This article explains the mechanism and methods for data collection, digitalization, preprocessing, and statistical analysis of colorimetric sensor array data. It also evaluates the applications of these methods in the past decade.
CHEMOMETRICS AND INTELLIGENT LABORATORY SYSTEMS
(2023)
Article
Chemistry, Analytical
Karla R. Borba, Fernanda C. A. Oldoni, Tatiana Monaretto, Luiz A. Colnago, Marcos D. Ferreira
Summary: This study successfully developed accurate and nondestructive classification models based on tomato maturation stage, SSC, and presence of defects using Time-Domain Nuclear Magnetic Resonance (TD-NMR) associated with computational classification methods. The results demonstrate the potential of TD-NMR technique in high-throughput screening applications in the tomato processing industry.
MICROCHEMICAL JOURNAL
(2021)
Article
Environmental Sciences
Chang-Young Ha, Beom-Jin Kim, Jae-Nam Lee, Byung-Hyun Kim
Summary: In this study, the sensitivity of parameters was analyzed to improve the accuracy of runoff and flooding analysis in urban areas using PEST. Six scenarios were created based on four highly sensitive parameters, and a combined simulation using PEST-SWMM was conducted. The results showed that considering only highly sensitive parameters led to improved accuracy and reduced calculation time. Furthermore, combining 2D flood analysis with other rainfall events can aid in real-time flood forecasting in urban areas.
Rating: 9/1
Article
Chemistry, Multidisciplinary
Huaxin Gong, Diego Uruchurtu Patino, Jan Ilavsky, Ivan Kuzmenko, Amnahir Estefania Pena-Alcantara, Chenhui Zhu, Aidan H. Coffey, Lukas Michalek, Ahmed Elabd, Xin Gao, Shucheng Chen, Chengyi Xu, Hongping Yan, Yuanwen Jiang, Weichen Wang, Yucan Peng, Yitian Zeng, Hao Lyu, Hanul Moon, Zhenan Bao
Summary: A versatile method for synthesizing nanostructured carbon materials based on flower-like PAN chemistry is reported. The resulting PAN superstructures can be easily converted to carbon superstructures. Surface modification of the nanostructured films resulted in high surface roughness and a contact angle of approximately 180 degrees. This study offers a strategy for the synthesis of nanostructured carbon materials for various applications.
Review
Nutrition & Dietetics
Elena Hayes, Derek Greene, Colm O'Donnell, Norah O'Shea, Mark A. Fenelon
Summary: Increasing consumer demand for safety, quality, and sustainability in food products has driven the need for rapid and accurate analytical techniques. Spectroscopy, combined with AI-enabled sensors and chemometric techniques, has enabled the fusion of data sources for dairy analysis. This article provides an overview of spectroscopic technologies in the dairy industry and introduces data fusion methods. It discusses the relevance of data fusion in improving predictions for processing traits using chemometric techniques and machine learning algorithms.
FRONTIERS IN NUTRITION
(2023)
Article
Chemistry, Inorganic & Nuclear
Xu Zhang, Zhiqing Liu, Xingchen Jin, Fengrui Liu, Xinlei Ma, Ning Qu, Wang Lu, Yuhan Tian, Qiang Zhang
Summary: Controllable modulation strategies for metal-organic frameworks (MOFs) with one-dimensional (1D) and two-dimensional (2D) structures are reported. The ratio of Ni2+ and pyromellitic acid linker can be adjusted to facilely prepare 1D, 1D/2D, and 2D Ni-MOFs. Low-dimensional structures can shorten transmission distance, while high Ni2+ content in MOFs provides abundant active sites for oxidation-reduction reactions. The optimized Ni2+/pyromellitic acid ratio in the 2D structure Ni-MOF shows a good performance of 1036 F g-1 at a current density of 1 A g-1 and a comparable rate performance of 62% at 20 A g-1. This study offers a facile design to control the structure of MOFs for electrochemical energy storage.
INORGANIC CHEMISTRY
(2023)
Article
Engineering, Electrical & Electronic
Jiabin Cui, Huashun Wen, Guo-Wei Lu, Yinfang Chen, Kunpeng Zhai, Ming Li, Ninghua Zhu
Summary: This paper introduces and reviews the advances of optical format conversion technologies, focusing on the format conversions between one dimensional and two dimensional constellation signals. The important enabling technologies for flexible constellation manipulation, including linear and nonlinear optical effects-based functions, are detailed. The key format conversion researches in four categories, including one-to-one conversions, optical aggregations, optical de-aggregations, and optical interconversions, are reviewed. Finally, the current issue and future trend of this research field are analyzed and discussed.
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
(2023)
Article
Chemistry, Multidisciplinary
Fan Wu, Ignacio Gutierrez-Lezama, Sara A. Lopez-Paz, Marco Gibertini, Kenji Watanabe, Takashi Taniguchi, Fabian O. von Rohr, Nicolas Ubrig, Alberto F. Morpurgo
Summary: Investigation on electronic transport through exfoliated multilayers of CrSBr, a 2D semiconductor, revealed a pronounced anisotropy along the crystallographic directions. The observed phenomenology and the detection of a 1D van Hove singularity in energy-resolved photocurrent measurements suggest that CrSBr exhibits quasi-1D electronic transport properties, unlike conventional 2D doped semiconductors.
ADVANCED MATERIALS
(2022)
Article
Biochemical Research Methods
Stef R. A. Molenaar, Mariyana Savova, Rebecca Cross, Paul D. Ferguson, Peter J. Schoenmakers, Bob W. J. Pirok
Summary: The prediction of chromatographic retention under supercritical-fluid chromatography conditions was studied using theoretical models. The study found that retention in SFC is strongly influenced by pressure and temperature, unlike liquid chromatography where retention models mainly consider the modifier fraction. The study explored the combination of multiple retention models to describe the effects of both modifier fraction and pressure. By using multivariate surfaces, retention-time prediction for isocratic separations at constant temperature improved significantly compared to univariate modeling when both pressure and modifier fractions were changed. The mixed-mode model with an additional exponential pressure or density parameter was able to predict retention times within 5%, with the majority of the predictions within 2%. The use of mass fraction and density further improved retention modeling compared to volume fraction and pressure, albeit requiring extra computations.
JOURNAL OF CHROMATOGRAPHY A
(2022)
Article
Chemistry, Analytical
Wouter C. Knol, Sifra Vos, Till Gruendling, Bob W. J. Pirok, Ron A. H. Peters
Summary: This study proposes a comprehensive workflow to ensure the accuracy of sequence determination in styrene-acrylate copolymers using Py-GC and 13C NMR. The results show that Py-GC consistently underestimates the acrylate sequence length, and calibration with 13C NMR is necessary for accurate absolute quantification. However, NMR calibration may not be required in all cases to obtain relative information on the sequence of a copolymer.
ANALYTICA CHIMICA ACTA
(2023)
Article
Biochemical Research Methods
Wouter C. Knol, Jasper P. H. Smeets, Till Gruendling, Bob W. J. Pirok, Ron A. H. Peters
Summary: It is important to understand the composition and molecular heterogeneities of complex industrial polymers to control their physical properties. This study developed an online method that combines liquid polymer chromatography with pyrolysis-GC (Py-GC) to analyze the composition and molar mass distribution of industrial polymers. The method allows for fractionation of the first-dimension effluent and efficient analysis of complex samples.
JOURNAL OF CHROMATOGRAPHY A
(2023)
Article
Biochemical Research Methods
Tijmen S. Bos, Jessica S. Desport, Ab Buijtenhuijs, Jindra Purmova, Leif Karlson, Bob W. J. Pirok, Peter J. Schoenmakers, Govert W. Somsen
Summary: Cellulose ethers (CEs) are semi-synthetic polymers derived from natural cellulose, and they exhibit various properties important for pharmaceutical and industrial applications. A new method using liquid chromatography-mass spectrometry (LC-MS) was developed to comprehensively analyze the substitution degree and composition of CE samples. This method allowed for the identification of compositional variations and unexpected methylations in CE samples, providing valuable molecular information for studying CE structure-property relationships.
JOURNAL OF CHROMATOGRAPHY A
(2023)
Article
Biochemical Research Methods
Wouter C. Knol, Ron A. H. Peters, Bob W. J. Pirok
Summary: This study evaluates the use of packed loops in modulation interfaces in 2D-LC and compares them to unpacked coiled and uncoiled modulation loops. The study found that packed loops reduce dispersion of chromatographic peaks compared to unpacked loops and uncoiled loops in all cases, with significantly reduced dispersion for larger loop volumes. Furthermore, countercurrent elution resulted in narrower elution profiles in all cases compared to concurrent elution. The study also suggests that packed loops are particularly useful when analytes are not refocused in the second-dimension separation.
JOURNAL OF CHROMATOGRAPHY A
(2023)
Article
Chemistry, Analytical
Leon E. Niezen, Jordy D. Kruijswijk, Gerben B. van Henten, Bob W. J. Pirok, Bastiaan B. P. Staal, Wolfgang Radke, Harry J. A. Philipsen, Govert W. Somsen, Peter J. Schoenmakers
Summary: The properties of a polymeric material are affected by its molecular distributions, such as molecular-weight (MWD), chemical-composition (CCD), and block-length (BLD) distributions. Gradient elution liquid chromatography (LC) is commonly used to determine the CCD. In this study, the potential of gradient size-exclusion chromatography (gSEC) for CCD analysis was explored and compared with conventional gradient-elution reversed-phase LC. The influence of mobile-phase composition, stationary-phase particle pore size, and column temperature was investigated.
ANALYTICA CHIMICA ACTA
(2023)
Article
Chemistry, Analytical
Wouter C. Knol, Quincy L. de Vries, Ton Brooijmans, Till Gruendling, Bob W. J. Pirok, Ron A. H. Peters
Summary: Size-exclusion chromatography (SEC) coupled with pyrolysis-gas chromatography (Py-GC) is a powerful tool for polymer analysis. However, the long analysis times of the Py-GC step limit its wider application. Therefore, an online hyphenated SECxPy-MS/FID method was developed, removing the need for GC separation and significantly reducing the second-dimension analysis time compared to SEC-Py-GC. The developed method showed no molar mass discrimination for masses above +/- 1.3 kDa, making it applicable to most commercial polymer systems. Multiple samples, including a complex industrial sample, were successfully analyzed using this method, providing information on chemical composition heterogeneity and molar mass distribution.
ANALYTICA CHIMICA ACTA
(2023)
Article
Chemistry, Analytical
Iro Konstantina Ventouri, Wayne Chang, Florian Meier, Roland Drexel, Govert W. Somsen, Peter J. Schoenmakers, Bart de Spiegeleer, Rob Haselberg, Alina Astefanei
Summary: We developed an online analytical platform combining asymmetrical flow field-flow fractionation (AF4) with native mass spectrometry (nMS) for studying labile higher-order structures (HOS) of protein biotherapeutics. The platform also utilizes UV absorbance, multi-angle light scattering (MALS), and differential refractive-index (UV-MALS-dRI) detectors. We studied the stability and dissociation pathways of the tetrameric biotherapeutic enzyme L-asparaginase (ASNase) and found the presence of intact octamers and degradation products using AF4-MALS/nMS. Exposure of ASNase to high pH disrupted the equilibrium between non-covalent species and led to HOS dissociation. The developed platform provides valuable insights for aggregation and stability studies of protein biopharmaceuticals.
ANALYTICAL CHEMISTRY
(2023)
Article
Chemistry, Analytical
Stef R. A. Molenaar, Wouter C. Knol, Bob W. J. Pirok, Ron A. H. Peters
Summary: Information about the number-average copolymer sequence length can be obtained through pyrolysis-gas chromatography (Py-GC) by comparing the ratios of formed oligomers. However, the formation constants of the oligomers and their detection efficiency are not constant, leading to unreliable peak ratios in the chromatogram. To address this, an algorithm is introduced to improve the accuracy of copolymer sequence from chromatograms with unrepresentative peak areas. The algorithm even works when oligomer data is missing.
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
(2023)
Article
Chemistry, Analytical
Hany A. Majeed, Tijmen S. Bos, Robert L. C. Voeten, Ruben F. Kranenburg, Arian C. van Asten, Govert W. Somsen, Isabelle Kohler
Summary: A method using trapped ion mobility spectrometry and time-of-flight mass spectrometry was developed to identify different ring-positional isomers in synthetic cathinones. The method allows for accurate ion mobility assessment and high-confidence isomer identification through narrow ion-trapping regions, internal reference mobility calibration, and a dedicated data analysis tool. The method was successfully applied to the unambiguous assignment of isomers in confiscated street samples.
ANALYTICA CHIMICA ACTA
(2023)
Article
Chemistry, Analytical
Leon E. Niezen, Tijmen S. Bos, Peter J. Schoenmakers, Govert W. Somsen, Bob W. J. Pirok
Summary: The time required for method development in gradient-elution LC can be reduced by using empirical modelling to describe analyte retention and peak width. However, accurate prediction is hindered by system-induced gradient deformation, which needs to be corrected for optimization and method transfer. Capacitively coupled contactless conductivity detection (C4D) can measure the exact gradient profiles, improving the transferability of retention models.
ANALYTICA CHIMICA ACTA
(2023)
Article
Biochemical Research Methods
Stef R. A. Molenaar, John H. M. Mommers, Dwight R. Stoll, Sithandile Ngxangxa, Andre J. de Villiers, Peter J. Schoenmakers, Bob W. J. Pirok
Summary: This article introduces a peak-tracking algorithm for comparing data in one-dimensional and two-dimensional chromatography. Two application strategies were investigated: simultaneous processing of all chromatograms and cumulative processing for method optimization. The accuracy and efficiency varied in different applications.
JOURNAL OF CHROMATOGRAPHY A
(2023)
Article
Biochemical Research Methods
Stef R. A. Molenaar, Tijmen S. Bos, Jim Boelrijk, Tina A. Dahlseid, Dwight R. Stoll, Bob W. J. Pirok
Summary: This article presents an open-source algorithm for automated and interpretive method development of complex gradients in LC x LC-MS. By enabling direct interaction between the LC x LC-MS system and a data-processing computer in a closed-loop, the algorithm improves efficiency. In testing, it successfully enhances separation and accuracy.
JOURNAL OF CHROMATOGRAPHY A
(2023)
Article
Polymer Science
Tijmen S. Bos, Harry J. A. Philipsen, Bastiaan B. P. Staal, Jindra Purmova, Rene J. L. Beerends, Ab Buijtenhuijs, Leif Karlson, Peter J. Schoenmakers, Govert W. Somsen
Summary: A new approach is proposed to gain additional insights from polymer molecular weight distribution and intrinsic viscosity using size-exclusion chromatography in combination with refractive index, viscometry, and multiangle light scattering detectors. The approach allows for a more quantitative interpretation of the Mark-Houwink plot and can be correlated to the structural and chemical properties of the polymer. The method can be used to assess the effect of solvent system and conditions on polymer solvation behavior.
JOURNAL OF APPLIED POLYMER SCIENCE
(2023)
