The Experts below are selected from a list of 4461 Experts worldwide ranked by ideXlab platform
Knut Irgum - One of the best experts on this subject based on the ideXlab platform.
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Retention and Selectivity of Nucleobases and Nucleosides in Hydrophilic Interaction Chromatography Investigated by Saturation Transfer Difference Nuclear Magnetic Resonance Spectroscopy
2020Co-Authors: Adel Shamshir, Ngoc Phuoc Dinh, Tobias Sparrman, Tobias Jonsson, Knut IrgumAbstract:Retention and Selectivity of Nucleobases and Nucleosides in Hydrophilic Interaction Chromatography Investigated by Saturation Transfer Difference Nuclear Magnetic Resonance Spectroscopy
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Interaction of toluene with polar stationary phases under conditions typical of Hydrophilic Interaction Chromatography probed by saturation transfer difference nuclear magnetic resonance spectroscopy
Journal of Chromatography A, 2019Co-Authors: Adel Shamshir, Ngoc Phuoc Dinh, Tobias Sparrman, Tobias Jonsson, Muhammad Jamshaid Ashiq, Knut IrgumAbstract:Toluene has been used as void volume (zero retention) marker since the inception of Hydrophilic Interaction Chromatography (HILIC), based on the assumption that its hydrophobicity should prevent it ...
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Tris(hydroxymethyl)aminomethane-functionalized silica particles and their application for Hydrophilic Interaction Chromatography.
IEEE Journal of Solid-state Circuits, 2010Co-Authors: Jeroen Verhage, Knut IrgumAbstract:A new method is presented for synthesizing a highly Hydrophilic silica-based material for use in Hydrophilic Interaction Chromatography. Porous silica particles used as a starting substrate were mo ...
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Preparation of a Silica-based Sorbitol Methacrylate Grafted Stationary Phase for Hydrophilic Interaction Chromatography
2007Co-Authors: Jonas Persson, Petrus Hemstrom, Knut IrgumAbstract:Preparation of a Silica-based Sorbitol Methacrylate Grafted Stationary Phase for Hydrophilic Interaction Chromatography
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Hydrophilic Interaction Chromatography
Journal of Separation Science, 2006Co-Authors: Petrus Hemstrom, Knut IrgumAbstract:Separation of polar compounds on polar stationary phases with partly aqueous eluents is by no means a new separation mode in LC. The first HPLC applications were published more than 30 years ago, and were for a long time mostly confined to carbohydrate analysis. In the early 1990s new phases started to emerge, and the practice was given a name, Hydrophilic Interaction Chromatography (HILIC). Al- though the use of this separation mode has been relatively limited, we have seen a sudden increase in popularity over the last few years, promoted by the need to ana- lyze polar compounds in increasingly complex mixtures. Another reason for the increase in popularity is the widespread use of MS coupled to LC. The partly aqueous eluents high in ACN with a limited need of adding salt is almost ideal for ESI. The applications now encompass most categories of polar compounds, charged as well as uncharged, although HILIC is particularly well suited for solutes lacking charge where coulombic Interactions cannot be used to mediate retention. The review attempts to summarize the ongoing discussion on the separation mechanism and gives an overview of the stationary phases used and the applications addressed with this separation mode in LC.
Sheetal Gaiki - One of the best experts on this subject based on the ideXlab platform.
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retention and selectivity of stationary phases for Hydrophilic Interaction Chromatography
Journal of Chromatography A, 2011Co-Authors: Yong Guo, Sheetal GaikiAbstract:More and more polar stationary phases have become available for the separation of small polar compounds in the past decade as Hydrophilic Interaction Chromatography (HILIC) continues to find applications in new fields (e.g., metabolomics and proteomics). Bare silica phases remain popular, especially in the bio-analytical area. A wide range of functional groups (e.g., amino, amide, diol, sulfobetaine, and triazole) have been employed as polar stationary phases for HILIC separation. This review provides a survey of the popular stationary phases commercially available and discusses the retention and selectivity characteristics of the polar stationary phases in HILIC. The purpose of the review is not to provide a comprehensive overview of literature reports, but rather focuses on findings that demonstrate retention and selectivity of the polar stationary phases in HILIC.
Yong Guo - One of the best experts on this subject based on the ideXlab platform.
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Evaluating Relative Retention of Polar Stationary Phases in Hydrophilic Interaction Chromatography
Separations, 2019Co-Authors: Yong Guo, Nidhi Bhalodia, Bassel FattalAbstract:A large number of polar stationary phases with diverse chemistry have been developed for various applications in Hydrophilic Interaction Chromatography (HILIC). However, column manufacturers employ different testing procedures to evaluate retention of the polar stationary phases. This renders the retention data impossible for comparison and makes it difficult for the users to select the right stationary phase based on retention. We have evaluated 25 polar stationary phases using cytosine and uracil as the model compounds in various mobile phase conditions. These stationary phases show a wide range of retention characteristics for the model compounds. The ranking of the stationary phases does not change drastically with the acetonitrile level in the mobile phase.
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Recent progress in the fundamental understanding of Hydrophilic Interaction Chromatography (HILIC)
The Analyst, 2015Co-Authors: Yong GuoAbstract:With the exponential growth in the application of the HILIC technique, there has been a significant progress in understanding the fundamental aspects of Hydrophilic Interaction Chromatography. The experimental studies tend to be more extensive in terms of the number of stationary phases investigated and the number of probe compounds employed in comparison with the earlier studies; and more theoretical studies in quantitative structure retention relationship (QSRR) and molecular dynamics simulations have also been published and provide molecular-level insights into the retention mechanism. This review focuses on the recent progress in understanding the retention mechanism, retention models, selectivity, and the kinetic performance of HILIC. A better understanding of these fundamental aspects will undoubtedly facilitate more applications of this chromatographic technique in a wider range of fields.
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retention and selectivity of stationary phases for Hydrophilic Interaction Chromatography
Journal of Chromatography A, 2011Co-Authors: Yong Guo, Sheetal GaikiAbstract:More and more polar stationary phases have become available for the separation of small polar compounds in the past decade as Hydrophilic Interaction Chromatography (HILIC) continues to find applications in new fields (e.g., metabolomics and proteomics). Bare silica phases remain popular, especially in the bio-analytical area. A wide range of functional groups (e.g., amino, amide, diol, sulfobetaine, and triazole) have been employed as polar stationary phases for HILIC separation. This review provides a survey of the popular stationary phases commercially available and discusses the retention and selectivity characteristics of the polar stationary phases in HILIC. The purpose of the review is not to provide a comprehensive overview of literature reports, but rather focuses on findings that demonstrate retention and selectivity of the polar stationary phases in HILIC.
Mark A Strege - One of the best experts on this subject based on the ideXlab platform.
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Quantitative determination of beta-cyclodextrin in a powder insulin formulation for nasal delivery using Hydrophilic Interaction Chromatography with evaporative light scattering detection
Journal of Liquid Chromatography & Related Technologies, 2019Co-Authors: Mark A Strege, Siyuan Huang, Donald S. RisleyAbstract:This study demonstrated the first application of Hydrophilic Interaction Chromatography (HILIC) with evaporative light scattering detection (ELSD) for the analysis of beta-cyclodextrin in a peptide...
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chiral separations of polar compounds by Hydrophilic Interaction Chromatography with evaporative light scattering detection
Analytical Chemistry, 2000Co-Authors: Donald S. Risley, Mark A StregeAbstract:The chiral separations of drug substances and underivatized amino acids were demonstrated in this study through the use of Hydrophilic Interaction Chromatography (HILIC). The polar character of the model compounds presented challenges for their analysis by traditional modes of Chromatography, but through the employment of multimodal Chromatography utilizing the HILIC mechanism and cyclodextrin- or teicoplanin-derivatized stationary phases, effective resolution was achieved. The analytes lacked sufficient ultraviolet chromophores, requiring their determination by evaporative light scattering detection. HILIC was demonstrated to represent a novel technique for the facilitation of chiral Chromatography by providing an environment of solubility and retention that could not be achieved through the use of the traditional methods of reversed-phase, normal-phase, or polar organic mode.
Joshua D Rabinowitz - One of the best experts on this subject based on the ideXlab platform.
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separation and quantitation of water soluble cellular metabolites by Hydrophilic Interaction Chromatography tandem mass spectrometry
Journal of Chromatography A, 2006Co-Authors: Sunil Bajad, Wenyun Lu, Elizabeth Kimball, Jie Yuan, Celeste N Peterson, Joshua D RabinowitzAbstract:A key unmet need in metabolomics is the ability to efficiently quantify a large number of known cellular metabolites. Here we present a liquid Chromatography (LC)–electrospray ionization tandem mass spectrometry (ESI-MS/MS) method for reliable measurement of 141 metabolites, including components of central carbon, amino acid, and nucleotide metabolism. The selected LC approach, Hydrophilic Interaction Chromatography with an amino column, effectively separates highly water soluble metabolites that fail to retain using standard reversed-phase Chromatography. MS/MS detection is achieved by scanning through numerous selected reaction monitoring events on a triple quadrupole instrument. When applied
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separation and quantitation of water soluble cellular metabolites by Hydrophilic Interaction Chromatography tandem mass spectrometry
Journal of Chromatography A, 2006Co-Authors: Sunil Bajad, Wenyun Lu, Elizabeth Kimball, Jie Yuan, Celeste N Peterson, Joshua D RabinowitzAbstract:A key unmet need in metabolomics is the ability to efficiently quantify a large number of known cellular metabolites. Here we present a liquid Chromatography (LC)-electrospray ionization tandem mass spectrometry (ESI-MS/MS) method for reliable measurement of 141 metabolites, including components of central carbon, amino acid, and nucleotide metabolism. The selected LC approach, Hydrophilic Interaction Chromatography with an amino column, effectively separates highly water soluble metabolites that fail to retain using standard reversed-phase Chromatography. MS/MS detection is achieved by scanning through numerous selected reaction monitoring events on a triple quadrupole instrument. When applied to extracts of Escherichia coli grown in [12C]- versus [13C]glucose, the method reveals appropriate 12C- and 13C-peaks for 79 different metabolites.
