1
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Kochale K, Cunha R, Teutenberg T, Schmidt TC. Development of a column switching for direct online enrichment and separation of polar and nonpolar analytes from aqueous matrices. J Chromatogr A 2024; 1714:464554. [PMID: 38065029 DOI: 10.1016/j.chroma.2023.464554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 11/28/2023] [Accepted: 11/30/2023] [Indexed: 01/05/2024]
Abstract
Trace substances in surface waters may threaten health and pose a risk for the aquatic environment. Moreover, separation and detection by instrumental analysis is challenging due to the low concentration and the wide range of polarities. Separation of polar and nonpolar analytes can be achieved by using stationary phases with different selectivity. Lower limits of detection of trace substances can be obtained by offline enrichment on solid phase materials. However, these practices require substantial effort and are time consuming and costly. Therefore, in this study, a column switching was developed to enrich and separate both polar and nonpolar analytes by an on-column large volume injection of aqueous samples. The column switching can significantly reduce the effort and time for analyzing trace substances without compromising on separation and detection. A reversed phase (RP) column is used to trap the nonpolar analytes. The polar analytes are enriched on a porous graphitized carbon column (PGC) coupled serially behind the RP column. A novel valve switching system is implemented to enable elution of the nonpolar analytes from the RP column and, subsequently, elution of polar analytes from the PGC column and separation on a hydrophilic interaction liquid chromatography (HILIC) column. To enable separation of polar analytes dissolved in an aqueous matrix by HILIC, the water plug that is flushed from the PGC column is diluted by dosing organic solvent directly upstream of the HILIC column. The developed method was tested by applying target analysis and non-target screening, highlighting the advantage to effectively separate and detect both polar and nonpolar compounds in a single chromatographic run. In the target analysis, the analytes, with a logD at pH 3 ranging from -2.8 to + 4.5, could be enriched and separated. Besides the 965 features in the RP phase, 572 features from real wastewater were observed in the HILIC phase which would otherwise elute in the void time in conventional one-dimensional RP methods.
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Affiliation(s)
- Kjell Kochale
- Institut für Umwelt & Energie, Technik & Analytik e. V. (IUTA), Bliersheimer Str. 58-60, 47229 Duisburg, Germany; Instrumental Analytical Chemistry, University of Duisburg-Essen, Universitätsstr. 5, 45141 Essen, Germany
| | - Ricardo Cunha
- Institut für Umwelt & Energie, Technik & Analytik e. V. (IUTA), Bliersheimer Str. 58-60, 47229 Duisburg, Germany
| | - Thorsten Teutenberg
- Institut für Umwelt & Energie, Technik & Analytik e. V. (IUTA), Bliersheimer Str. 58-60, 47229 Duisburg, Germany.
| | - Torsten C Schmidt
- Instrumental Analytical Chemistry, University of Duisburg-Essen, Universitätsstr. 5, 45141 Essen, Germany
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2
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Caño-Carrillo I, Martínez-Piernas AB, Gilbert-López B, Molina-Díaz A, García-Reyes JF. Simultaneous analysis of highly polar and multi-residue-type pesticides by heart-cutting 2D-LC-MS. Talanta 2024; 266:124918. [PMID: 37454518 DOI: 10.1016/j.talanta.2023.124918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 07/03/2023] [Accepted: 07/05/2023] [Indexed: 07/18/2023]
Abstract
Liquid chromatography-mass spectrometry (LC-MS) is currently the gold-standard technique for the analysis of non-volatile small organic molecules. However, one-dimensional liquid chromatography (1D-LC) cannot efficiently deal with mixtures of analytes with different physicochemical properties and, thus, specific chromatographic behaviour. As an alternative, this work proposes a two-dimensional liquid chromatography/high-resolution mass spectrometry (2D-LC-HRMS) approach for the simultaneous analysis of compounds with different polarities. It is based on the combination of hydrophilic interaction liquid chromatography (HILIC) in the first dimension (1D) and reversed-phase chromatography (RPLC) in the second dimension (2D), employing the heart-cutting methodology. The coupling between 1D and 2D was performed by a multiple heart-cutting (MHC) interface equipped with an active solvent modulation (ASM) valve. The aim of the study was the development of a 2D-LC methodology able to (i) acquire the 1D and 2D content by MS in a single analytical run, avoiding the loss of information caused by the MHC algorithm for filling the sampling loops; (ii) overcome the breakthrough problem caused by solvent incompatibility, modifying the 2D gradient during the ASM phase for this purpose. To evaluate the 2D-LC approach, pesticide residue analysis was proposed, selecting 20 pesticides covering a wide range of polarities (log Kow from -3.2 to 4.3) and including some of the so-called single residue method pesticides because of the difficulty of including them in 1D-LC multi-residue methods with satisfactory chromatographic resolution. The proposed strategy was to transfer in a single cut the void volume from the HILIC separation (consisting of the nonpolar pesticides) to the 2D for analysis under RPLC conditions. The developed assembly was assessed in a vegetable matrix (tomato) employing a hybrid QuEChERS/QuPPe sample treatment based on acetonitrile and methanol extraction. The proposed setup may be extended for 2D-LC applications where it is essential to acquire the entire content of both dimensions in a single data file just by coupling a selection valve to the MHC interface.
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Affiliation(s)
- Irene Caño-Carrillo
- Analytical Chemistry Research Group, Department of Physical and Analytical Chemistry, University of Jaén, Campus Las Lagunillas, 23071, Jaén, Spain
| | - Ana B Martínez-Piernas
- Analytical Chemistry Research Group, Department of Physical and Analytical Chemistry, University of Jaén, Campus Las Lagunillas, 23071, Jaén, Spain
| | - Bienvenida Gilbert-López
- Analytical Chemistry Research Group, Department of Physical and Analytical Chemistry, University of Jaén, Campus Las Lagunillas, 23071, Jaén, Spain; University Research Institute for Olives Grove and Olive Oil, University of Jaén, Campus Las Lagunillas, 23071, Jaén, Spain
| | - Antonio Molina-Díaz
- Analytical Chemistry Research Group, Department of Physical and Analytical Chemistry, University of Jaén, Campus Las Lagunillas, 23071, Jaén, Spain; University Research Institute for Olives Grove and Olive Oil, University of Jaén, Campus Las Lagunillas, 23071, Jaén, Spain
| | - Juan F García-Reyes
- Analytical Chemistry Research Group, Department of Physical and Analytical Chemistry, University of Jaén, Campus Las Lagunillas, 23071, Jaén, Spain; University Research Institute for Olives Grove and Olive Oil, University of Jaén, Campus Las Lagunillas, 23071, Jaén, Spain.
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3
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Chapel S, Rouvière F, Guillarme D, Heinisch S. Reversed HILIC Gradient: A Powerful Strategy for On-Line Comprehensive 2D-LC. Molecules 2023; 28:molecules28093907. [PMID: 37175317 PMCID: PMC10179806 DOI: 10.3390/molecules28093907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 04/25/2023] [Accepted: 04/27/2023] [Indexed: 05/15/2023] Open
Abstract
The aim of the present work is to evaluate the possibilities and limitations of reversed hydrophilic interaction chromatography (revHILIC) mode in liquid chromatography (LC). This chromatographic mode consists of combining a highly polar stationary phase (bare silica) with a gradient varying from very low (1-5%) to high (40%) acetonitrile content (reversed gradient compared to HILIC). The retention behavior of revHILIC was first compared with that of reversed-phase LC (RPLC) and HILIC using representative mixtures of peptides and pharmaceutical compounds. It appears that the achievable selectivity can be ranked in the order RPLC > revHILIC > HILIC with the two different samples. Next, two-dimensional liquid chromatography (2D-LC) conditions were evaluated by combining RPLC, revHILIC, or HILIC with RPLC in an on-line comprehensive (LC × LC) mode. evHILIC × RPLC not only showed impressive performance in terms of peak capacity and sensitivity, but also provided complementary selectivity compared to RPLC × RPLC and HILIC × RPLC. Indeed, both the elution order and the retention time range differ significantly between the three techniques. In conclusion, there is no doubt that revHILIC should be considered as a viable option for 2D-LC analysis of small molecules and also peptides.
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Affiliation(s)
- Soraya Chapel
- Institut Des Sciences Analytiques, Université de Lyon, UMR 5280, CNRS, 5 rue de la Doua, 69100 Villeurbanne, France
- Pharmaceutical Analysis, Department of Pharmaceutical and Pharmacological Sciences, University of Leuven (KU Leuven), Herestraat 49, 3000 Leuven, Belgium
| | - Florent Rouvière
- Institut Des Sciences Analytiques, Université de Lyon, UMR 5280, CNRS, 5 rue de la Doua, 69100 Villeurbanne, France
| | - Davy Guillarme
- School of Pharmaceutical Sciences, University of Geneva, CMU-Rue Michel Servet 1, 1211 Geneva 4, Switzerland
- Institute of Pharmaceutical Sciences of Western Switzerland, University of Geneva, CMU-Rue Michel Servet 1, 1211 Geneva 4, Switzerland
| | - Sabine Heinisch
- Institut Des Sciences Analytiques, Université de Lyon, UMR 5280, CNRS, 5 rue de la Doua, 69100 Villeurbanne, France
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4
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Lin Z, Wang Q, Zhou Y, Shackman JG. Trapping mode two-dimensional liquid chromatography for quantitative low-level impurity enrichment in pharmaceutical development. J Chromatogr A 2023; 1700:464043. [PMID: 37172541 DOI: 10.1016/j.chroma.2023.464043] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 04/20/2023] [Accepted: 05/02/2023] [Indexed: 05/15/2023]
Abstract
Trapping mode two-dimensional liquid chromatography (2D-LC) has recently found applications in pharmaceutical analysis to clean, refocus, and enrich analytes. Given its enrichment capability, 2D-LC with multiple trappings is appealing for low-level impurity monitoring that cannot be solved by single dimensional LC (1D-LC) or unenriched 2D-LC analysis. However, the quantitative features of multi-trapping 2D-LC remain largely unknown at impurity levels from parts-per-million (ppm) to 0.15% (w/w). We present a simple heart-cutting trapping mode 2D-LC workflow using only common components and software found in typical off-the-shelf 1D-LC instruments. This robust, turn-key system's quantitative capabilities were evaluated using a variety of standard markers, demonstrating linear enrichment for up to 20 trapping cycles and achieving a recovery of over 97.0%. Next, the trapping system was applied to several real-world low-level impurity pharmaceutical case studies including (1) the identification of two unknown impurities at sub-ppm levels resulting in material discoloration, (2) the discovery of a new impurity at 0.05% (w/w) co-eluted with a known impurity, making the undesired summation above the target specification, and (3) the quantification of a potential mutagenic impurity at 10-ppm level in a poorly soluble substrate. The recovery in all studies was better than 97.0% with RSD lower than 3.0%, demonstrating accuracy and precision of the 2D-LC trapping workflow. As no specialized equipment or software is required, we envision that the system could be used to develop low-impurity monitoring methods suitable for validation and potential execution in quality-control laboratories.
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Affiliation(s)
- Ziqing Lin
- Bristol Myers Squibb Company, Chemical Process Development, One Squibb Drive, New Brunswick, NJ 08903, USA.
| | - Qinggang Wang
- Bristol Myers Squibb Company, Chemical Process Development, One Squibb Drive, New Brunswick, NJ 08903, USA
| | - Yiyang Zhou
- Bristol Myers Squibb Company, Chemical Process Development, One Squibb Drive, New Brunswick, NJ 08903, USA
| | - Jonathan G Shackman
- Bristol Myers Squibb Company, Chemical Process Development, One Squibb Drive, New Brunswick, NJ 08903, USA
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5
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Optimizing transfer and dilution processes when using active solvent modulation in on-line two-dimensional liquid chromatography. Anal Chim Acta 2023; 1252:341040. [PMID: 36935135 DOI: 10.1016/j.aca.2023.341040] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 03/01/2023] [Accepted: 03/02/2023] [Indexed: 03/06/2023]
Abstract
Two-dimensional liquid chromatography (2D-LC) is becoming increasingly popular for the analysis of complex samples, which is partly due to the recent introduction of commercial 2D-LC systems. To deal with the mobile phase incompatibility between highly orthogonal retention mechanisms, such as hydrophilic interaction liquid chromatography (HILIC) and reversed-phase LC (RPLC), several strategies have been introduced over the years. One of these strategies is active solvent modulation (ASM), a valve-based approach allowing the on-line dilution of the effluent eluting from the first dimension before transfer to the second dimension. This strategy has gained a lot of attention and holds great potential, however, no clear guidelines are currently in place for its use. Therefore, this study aims to investigate how the ASM process can be optimized when using highly incompatible LC combinations, such as HILIC and RPLC, in a simplified selective comprehensive 2D-LC set-up (sHILIC x RPLC) to suggest guidelines for future users. Using a representative sample, the dilution factor (DF), the duration of the ASM phase, the filling percentage of the sample loops, and their unloading configuration are investigated and optimized. It is observed that a DF of 10 with an optimal ASM phase duration, a sample loop filling of maximum 25%, and an unloading configuration in backflush mode, result in the best peak shapes, intensities, and recoveries for early eluting compounds, while keeping the total analysis time minimal. Based on these results, some general recommendations are made that could also be applied in other 2D-LC modes, such as comprehensive 2D-LC (LC x LC), heart-cutting 2D-LC (LC-LC), and other chromatographic combinations with mobile phase incompatibility issues.
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6
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Enhancing the compatibility of normal-phase chromatography x reversed-phase chromatography by combination of low-temperature sensitive aqueous-phase compatible normal- phase chromatography and at-column dilution modulation. J Chromatogr A 2023; 1691:463821. [PMID: 36724722 DOI: 10.1016/j.chroma.2023.463821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 01/19/2023] [Accepted: 01/21/2023] [Indexed: 01/27/2023]
Abstract
The nearly opposite retention mechanism in the two-dimensional liquid chromatography (2D-LC), which combines normal phase liquid chromatography (NPLC) and reversed phase liquid chromatography (RPLC), shows extremely high orthogonality and theoretical peak capacity. However, peak breakthrough and peak distortion caused by the highly incompatible 2D mobile phases counteracts the advantages offered by high orthogonality. To address this difficulty, this study proposes a comprehensive two-dimensional NPLC × RPLC integrating temperature-sensitive aqueous-phase compatible normal-phase chromatography (TSACNPLC) and at-column dilution modulation (ACDM). The proposed 2D-LC system uses an aqueous-miscible acetonitrile/methanol eluent in the 1st D NPLC, instead of an aqueous-phase immiscible eluent, such as n-hexane/methanol, to increase the miscibility with the RP mobile phase system. Additionally, the system exploits temperature-sensitive retention behavior to enhance the retention ability of aqueous-phase compatible NPLC. To verify the feasibility of the proposed 2D-LC, this study selected three multi-component samples with mid-to-low polarity, including ethoxylated (n ≈ 6) bisphenol A (BPA-6EO), ethoxylated (n ≈ 6) tristearylphenol (TSP-6EO), and safflower methanol extract. Next, the effectiveness of the constructed 2D-LC was systematically investigated, including low temperature-induced retention enhancement of NPLC, overcoming solvent incompatibility by ACDM, and optimization of 2 D separation conditions, was systematically investigated.
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7
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Tang S, Venkatramani CJ. Resolving Solvent Incompatibility in Two-Dimensional Liquid Chromatography with In-Line Mixing Modulation. Anal Chem 2022; 94:16142-16150. [DOI: 10.1021/acs.analchem.2c03572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Shijia Tang
- Small Molecule Analytical Chemistry, Genentech, 1 DNA Way, South San Francisco, California 94080, United States
| | - Cadapakam J. Venkatramani
- Small Molecule Analytical Chemistry, Genentech, 1 DNA Way, South San Francisco, California 94080, United States
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8
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van den Hurk RS, Abdulhussain N, van Beurden AS, Dekker ME, Hulsbergen A, Peters RA, Pirok BW, van Asten AC. Characterization and comparison of smokeless powders by on-line two-dimensional liquid chromatography. J Chromatogr A 2022; 1672:463072. [DOI: 10.1016/j.chroma.2022.463072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 04/13/2022] [Accepted: 04/14/2022] [Indexed: 10/18/2022]
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9
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Yang P, Gao W, Pursch M, Luong J. Gaining New Insights in Advanced Polymeric Materials Using Comprehensive Two-Dimensional Liquid Chromatography. LCGC NORTH AMERICA 2022. [DOI: 10.56530/lcgc.na.xh1183h9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Two-dimensional liquid chromatography (2D-LC) offers new insights into modern polymeric materials such as biodegradable polymers, polymers made from renewable feedstock, and complex formulated systems. Advances in instrumentation and the development of new modulation techniques enable more combinations of different separation modes. Hyphenation with universal and information-rich detectors further enhances the versatility and flexibility of the analytical strategy. Detailed characterization of copolymer composition heterogeneity and identification of polymeric ingredients in complex consumer products are key highlights of new applications.
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10
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Groeneveld G, Dunkle MN, Pursch M, Mes EP, Schoenmakers PJ, Gargano AF. Investigation of the Effects of Solvent-Mismatch and Immiscibility in Normal-Phase × Aqueous Reversed-Phase Liquid Chromatography. J Chromatogr A 2022; 1665:462818. [DOI: 10.1016/j.chroma.2022.462818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 11/28/2021] [Accepted: 01/07/2022] [Indexed: 11/28/2022]
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11
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Groeneveld G, Salome R, Dunkle MN, Bashir M, Gargano AFG, Pursch M, Mes EPC, Schoenmakers PJ. Fast determination of functionality-type × molecular-weight distribution of propoxylates with varying numbers of hydroxyl end-groups using gradient-normal-phase liquid chromatography × ultra-high pressure size-exclusion chromatography. J Chromatogr A 2021; 1659:462644. [PMID: 34739964 DOI: 10.1016/j.chroma.2021.462644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 10/16/2021] [Accepted: 10/21/2021] [Indexed: 10/20/2022]
Abstract
Understanding the relation between chemical characteristics and properties of synthetic polymers is one of the challenges faced by analytical chemists in industry. This is a complex task, as polymers are not synthesized as single molecule, but are populations of chemically similar compounds with distributions over several properties. The latter include, for example, molecular weight, nature of end-groups (functionality), and chemical composition. In this paper, comprehensive two-dimensional liquid chromatography was used to determine the combined functionality-type and molecular-weight distributions of hydroxy‑functionalized propoxylates. Propoxylates derived from different initiators (one up to eight terminal hydroxyl groups) were separated in the first dimension using a gradient normal-phase LC separation (NPLC). In the second dimension ultra-high pressure size-exclusion chromatography separation (UHPSEC), further speciating distributions based on molecular size. The developed NPLC × SEC method with evaporative light-scattering detection can be used for the fast screening (< 30 min) of mutually dependent functionality-type and molecular-weight distributions of unknown propoxylates.
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Affiliation(s)
- Gino Groeneveld
- University of Amsterdam, Van 't Hoff Institute for Molecular Sciences, Science Park 904, 1098 XH Amsterdam, the Netherlands.
| | - Ron Salome
- Dow, Analytical Science, P.O. Box 48, 4530 AA Terneuzen, the Netherlands
| | - Melissa N Dunkle
- Dow, Analytical Science, P.O. Box 48, 4530 AA Terneuzen, the Netherlands
| | - Mubasher Bashir
- Dow, Analytical Science, P.O. Box 48, 4530 AA Terneuzen, the Netherlands
| | - Andrea F G Gargano
- University of Amsterdam, Van 't Hoff Institute for Molecular Sciences, Science Park 904, 1098 XH Amsterdam, the Netherlands
| | | | - Edwin P C Mes
- Dow, Analytical Science, P.O. Box 48, 4530 AA Terneuzen, the Netherlands
| | - Peter J Schoenmakers
- University of Amsterdam, Van 't Hoff Institute for Molecular Sciences, Science Park 904, 1098 XH Amsterdam, the Netherlands
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12
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Chapel S, Heinisch S. Strategies to circumvent the solvent strength mismatch problem in online comprehensive two-dimensional liquid chromatography. J Sep Sci 2021; 45:7-26. [PMID: 34525266 DOI: 10.1002/jssc.202100534] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 08/23/2021] [Accepted: 08/24/2021] [Indexed: 11/09/2022]
Abstract
On-line comprehensive two-dimensional liquid chromatography is a powerful technique for the separation of highly complex samples. Due to the addition of the second dimension of separation, impressive peak capacities can be obtained within a reasonable analysis time compared to one-dimensional liquid chromatography. In online comprehensive two-dimensional liquid chromatography, the separation power is maximized by selecting two separation dimensions as orthogonal as possible, which most often requires the combination of different mobile phases and stationary phases. The online transfer of a given solvent from the first dimension to the second dimension may cause severe injection effects in the second dimension, mostly due to solvent strength mismatch. Those injection effects may include peak broadening, peak distortion, peak splitting or breakthrough phenomenon. They are often found to reduce significantly the peak capacity and the peak intensity. To overcome such effects, arising specifically in online comprehensive two-dimensional liquid chromatography, different methods have been developed over the years. In this review, we focused on the most recently reported ones. A critical discussion, supported by a theoretical approach, gives an overview of their advantages and drawbacks.
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Affiliation(s)
- Soraya Chapel
- Université de Lyon, Institut des sciences analytiques, Villeurbanne, France
| | - Sabine Heinisch
- Université de Lyon, Institut des sciences analytiques, Villeurbanne, France
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13
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Haidar Ahmad IA, Makey DM, Wang H, Shchurik V, Singh AN, Stoll DR, Mangion I, Regalado EL. In Silico Multifactorial Modeling for Streamlined Development and Optimization of Two-Dimensional Liquid Chromatography. Anal Chem 2021; 93:11532-11539. [PMID: 34375071 DOI: 10.1021/acs.analchem.1c01970] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Continued adoption of two-dimensional liquid chromatography (2D-LC) in industrial laboratories will depend on the development of approaches to make method development for 2D-LC more systematic, less tedious, and less reliant on user expertise. In this paper, we build on previous efforts in these directions by describing the use of multifactorial modeling software that can help streamline and simplify the method development process for 2D-LC. Specifically, we have focused on building retention models for second dimension (2D) separations involving variables including gradient time, temperature, organic modifier blending, and buffer concentration using LC simulator (ACD/Labs) software. Multifactorial retention modeling outcomes are illustrated as resolution map planes or cubes that enable straightforward location of 2D conditions that maximize resolution while minimizing analysis time. We also illustrate the practicality of this approach by identifying conditions that yield baseline separation of all compounds co-eluting from a first dimension (1D) separation using a single combination of 2D stationary phase and elution conditions. The multifactorial retention models were found to be very accurate for both the 1D and 2D separations, with differences between experimental and simulated retention times of less than 0.5%. Pharmaceutical applications of this approach for multiple heartcutting 2D-LC were demonstrated using IEC-IEC or achiral RPLC-chiral RPLC for 2D separations of multicomponent mixtures. The framework outlined here should help make 2D-LC method development more systematic and streamline development and optimization for a variety of 2D-LC applications in both industry and academia.
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Affiliation(s)
- Imad A Haidar Ahmad
- Analytical Research and Development, MRL, Merck & Co., Inc., Rahway, New Jersey 07065, United States
| | - Devin M Makey
- Analytical Research and Development, MRL, Merck & Co., Inc., Rahway, New Jersey 07065, United States.,Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Heather Wang
- Analytical Research and Development, MRL, Merck & Co., Inc., Rahway, New Jersey 07065, United States
| | - Vladimir Shchurik
- Analytical Research and Development, MRL, Merck & Co., Inc., Rahway, New Jersey 07065, United States
| | - Andrew N Singh
- Analytical Research and Development, MRL, Merck & Co., Inc., Rahway, New Jersey 07065, United States
| | - Dwight R Stoll
- Department of Chemistry, Gustavus Adolphus College, Saint Peter, Minnesota 56082, United States
| | - Ian Mangion
- Analytical Research and Development, MRL, Merck & Co., Inc., Rahway, New Jersey 07065, United States
| | - Erik L Regalado
- Analytical Research and Development, MRL, Merck & Co., Inc., Rahway, New Jersey 07065, United States
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14
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Pepermans V, Chapel S, Heinisch S, Desmet G. Detailed numerical study of the peak shapes of neutral analytes injected at high solvent strength in short reversed-phase liquid chromatography columns and comparison with experimental observations. J Chromatogr A 2021; 1643:462078. [PMID: 33780885 DOI: 10.1016/j.chroma.2021.462078] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 03/10/2021] [Accepted: 03/13/2021] [Indexed: 12/27/2022]
Abstract
We report on a numerical investigation of the different steps in the development of the spatial concentration profiles developing along the axis of a liquid chromatography column when injecting large relative volumes (>10 to 20% of column volume) of analytes dissolved in a high solvent strength solvent band as can be encountered in the second dimension (2D) column of a two-dimensional liquid chromatography (2D-LC) system. More specifically, we made a detailed study of the different retention and the axial band broadening effects leading to the double-headed peak shapes or strongly fronting peaks that can be experimentally observed under certain conditions in 2D-LC. The establishment of these intricate peak profiles is discussed in all its fine, mechanistic details. The effect of the volume of the column, the volume and the shape of the sample band, the retention properties of the analyte and the band broadening experienced by the analytes and the sample solvent are investigated. A good agreement between the simulations and the experimental observations with caffeine and methylparaben injected in acetonitrile/water (ACN/H2O) mobile phase with different injection volumes is obtained. Save the difference in dwell volume, key features of experimental and simulated chromatograms agree within a few %. The simulations are also validated against a number of simple mathematical rules of thumb that can be established to predict the occurrence of a breakthrough fraction and estimate the amount of breakthrough.
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Affiliation(s)
- Vincent Pepermans
- Department of Chemical Engineering, Vrije Universiteit Brussel, Brussels, Belgium
| | - Soraya Chapel
- Université de Lyon, Institut des Sciences Analytiques, UMR 5280, CNRS, 5 rue de la Doua, 69100, Villeurbanne, France
| | - Sabine Heinisch
- Université de Lyon, Institut des Sciences Analytiques, UMR 5280, CNRS, 5 rue de la Doua, 69100, Villeurbanne, France
| | - Gert Desmet
- Department of Chemical Engineering, Vrije Universiteit Brussel, Brussels, Belgium.
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15
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Shoykhet K, Stoll D, Buckenmaier S. Constant pressure mode of operation in the second dimension of two-dimensional liquid chromatography: A proof of concept. J Chromatogr A 2021; 1639:461880. [PMID: 33508638 DOI: 10.1016/j.chroma.2021.461880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Revised: 12/28/2020] [Accepted: 12/30/2020] [Indexed: 10/22/2022]
Abstract
The use of two-dimensional liquid chromatography (2D-LC) continues to grow as the advantages over 1D-LC become increasingly clear in specific application areas, and the number of experienced 2D-LC users increases. As with any technique, however, there is always room for innovation that could improve the performance of 2D-LC. In recent years the technical aspects and potential benefits of a volume-based mode of operation were studied in detail for 1D-LC. The salient features of this approach that are immediately interesting for use in 2D-LC are two-fold. First, the ability to maintain a nominally constant pressure in the second dimension by dynamically adjusting the flow rate to compensate for changes in the viscosity of the fluid in the 2D flow path provides a means to more fully utilize the pressure capability of the pumping system, and accelerates separations in the second dimension (2D). Second, constant pressure operation minimizes physical stress on the system components and the 2D column. In this paper we discuss the aspects of volume-based operation of LC that are particularly relevant to 2D-LC systems. The proof-of-concept experiments illustrate the viability of the constant pressure mode of operation for the second dimension of 2D-LC. In the described separations the throughput improvement is on the order of 10%; this gain will be strongly application-dependent, and may be as large as several tens percent in some cases. Future work will involve a detailed investigation of the impact of the constant pressure mode on robustness of 2D separations.
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Affiliation(s)
- Konstantin Shoykhet
- Agilent Technologies R&D and Marketing GmbH & Co KG, Hewlett-Packard-Str. 8, Waldbronn, 76337, Germany.
| | - Dwight Stoll
- Gustavus Adolphus College, 800 West College Avenue, St. Peter, MN 56082, United States
| | - Stephan Buckenmaier
- Agilent Technologies R&D and Marketing GmbH & Co KG, Hewlett-Packard-Str. 8, Waldbronn, 76337, Germany
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16
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Meunier DM, Wade JH, Janco M, Cong R, Gao W, Li Y, Mekap D, Wang G. Recent Advances in Separation-Based Techniques for Synthetic Polymer Characterization. Anal Chem 2020; 93:273-294. [DOI: 10.1021/acs.analchem.0c04352] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- David M. Meunier
- Core R&D, Analytical Science, The Dow Chemical Company, Midland, Michigan 48640, United States
| | - James H. Wade
- Core R&D, Analytical Science, The Dow Chemical Company, Midland, Michigan 48640, United States
| | - Miroslav Janco
- Core R&D, Analytical Science, The Dow Chemical Company, Collegeville, Pennsylvania 19426, United States
| | - Rongjuan Cong
- Packaging and Specialty Plastics, Characterization, The Dow Chemical Company, Lake Jackson, Texas 77566, United States
| | - Wei Gao
- Core R&D, Analytical Science, The Dow Chemical Company, Collegeville, Pennsylvania 19426, United States
| | - Yongfu Li
- Core R&D, Analytical Science, The Dow Chemical Company, Midland, Michigan 48640, United States
| | - Dibyaranjan Mekap
- Packaging and Specialty Plastics, Characterization, Dow Benelux, 4542 NM Terneuzen, The Netherlands
| | - Grace Wang
- School of Cinematic Arts, University of Southern California, Los Angeles, California 90089, United States
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17
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Liu S, Li Z, Yu B, Wang S, Shen Y, Cong H. Recent advances on protein separation and purification methods. Adv Colloid Interface Sci 2020; 284:102254. [PMID: 32942182 DOI: 10.1016/j.cis.2020.102254] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 09/01/2020] [Accepted: 09/01/2020] [Indexed: 12/21/2022]
Abstract
Protein, as the material basis of vita, is the crucial undertaker of life activities, which constitutes the framework and main substance of human tissues and organs, and takes part in various forms of life activities in organisms. Separating proteins from biomaterials and studying their structures and functions are of great significance for understanding the law of life activities and clarifying the essence of life phenomena. Therefore, scientists have proposed the new concept of proteomics, in which protein separation technology plays a momentous role. It has been diffusely used in the food industry, agricultural biological research, drug development, disease mechanism, plant stress mechanism, and marine environment research. In this paper, combined with the recent research situation, the progress of protein separation technology was reviewed from the aspects of extraction, precipitation, membrane separation, chromatography, electrophoresis, molecular imprinting, microfluidic chip and so on.
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18
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Huygens B, Efthymiadis K, Nowé A, Desmet G. Application of evolutionary algorithms to optimise one- and two-dimensional gradient chromatographic separations. J Chromatogr A 2020; 1628:461435. [PMID: 32822975 DOI: 10.1016/j.chroma.2020.461435] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 07/09/2020] [Accepted: 07/27/2020] [Indexed: 11/30/2022]
Abstract
We report on the performance of three classes of evolutionary algorithms (genetic algorithms (GA), evolution strategies (ES) and covariance matrix adaptation evolution strategy (CMA-ES)) as a means to enhance searches in the method development spaces of 1D- and 2D-chromatography. After optimisation of the design parameters of the different algorithms, they were benchmarked against the performance of a plain grid search. It was found that all three classes significantly outperform the plain grid search, especially in terms of the number of search runs needed to achieve a given separation quality. As soon as more than 100 search runs are needed, the ES algorithm clearly outperforms the GA and CMA-ES algorithms, with the latter performing very well for short searches (<50 search runs) but being susceptible to convergence to local optima for longer searches. It was also found that the performance of the ES and GA algorithms, as well as the grid search, follow a hyperbolic law in the large search run number limit, such that the convergence rate parameter of this hyperbolic function can be used to quantify the difference in required number of search runs for these algorithms. In agreement with one's physical expectations, it was also found that the general advantage of the GA and ES algorithms over the grid search, as well as their mutual performance differences, grow with increasing difficulty of the separation problem.
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Affiliation(s)
- Bram Huygens
- Vrije Universiteit Brussel, Department of Chemical Engineering, Pleinlaan 2, 1050 Brussels, Belgium
| | - Kyriakos Efthymiadis
- Vrije Universiteit Brussel, Artificial Intelligence Lab, Pleinlaan 2, 1050 Brussels, Belgium
| | - Ann Nowé
- Vrije Universiteit Brussel, Artificial Intelligence Lab, Pleinlaan 2, 1050 Brussels, Belgium
| | - Gert Desmet
- Vrije Universiteit Brussel, Department of Chemical Engineering, Pleinlaan 2, 1050 Brussels, Belgium.
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19
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Moussa A, Lauer T, Stoll D, Desmet G, Broeckhoven K. Numerical and experimental investigation of analyte breakthrough from sampling loops used for multi-dimensional liquid chromatography. J Chromatogr A 2020; 1626:461283. [DOI: 10.1016/j.chroma.2020.461283] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 05/26/2020] [Accepted: 05/27/2020] [Indexed: 11/17/2022]
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20
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Yang SH, Chen B, Wang J, Zhang K. Characterization of High Molecular Weight Multi-Arm Functionalized PEG–Maleimide for Protein Conjugation by Charge-Reduction Mass Spectrometry Coupled to Two-Dimensional Liquid Chromatography. Anal Chem 2020; 92:8584-8590. [DOI: 10.1021/acs.analchem.0c01567] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Samuel H. Yang
- Research and Early Development, Genentech Inc., 1 DNA Way, South San Francisco, California 94080, United States
| | - Bifan Chen
- Research and Early Development, Genentech Inc., 1 DNA Way, South San Francisco, California 94080, United States
| | - Jenny Wang
- Research and Early Development, Genentech Inc., 1 DNA Way, South San Francisco, California 94080, United States
| | - Kelly Zhang
- Research and Early Development, Genentech Inc., 1 DNA Way, South San Francisco, California 94080, United States
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21
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Groeneveld G, Pirok BWJ, Schoenmakers PJ. Perspectives on the future of multi-dimensional platforms. Faraday Discuss 2020; 218:72-100. [PMID: 31140485 DOI: 10.1039/c8fd00233a] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Two-dimensional liquid chromatography (2D-LC) formats have emerged to help address separation problems that are too complex for conventional one-dimensional LC. There are a number of obstacles to the proliferation of 2D-LC that are gradually being removed. Reliable commercial instrumentation has become available and data analysis software is being improved. Detector-sensitivity and phase-system compatibility issues can largely be solved by using active-modulation strategies. The remaining challenge, developing good and fast 2D-LC methods within a reasonable time, may be solved with smart algorithms. The technology platform that has been developed for 2D-LC also creates a number of other possibilities. Between the two separation stages, all kinds of physical (e.g. dissolution) or chemical (e.g. enzymatic or light-induced degradation) processes can be made to take place, allowing a wide variety of experiments to be performed within a single, efficient and automated analysis. All these developments are discussed in this paper and a number of critical issues are identified. A practical example, the characterization of polysorbates by high-resolution comprehensive two-dimensional liquid chromatography in combination with high-resolution mass spectrometry, is described as a culmination of recent developments in 2D-LC and as an illustration of the current state of the art.
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Affiliation(s)
- Gino Groeneveld
- University of Amsterdam, van 't Hoff Institute for Molecular Sciences, Analytical-Chemistry Group, Science Park 904, 1098 XH Amsterdam, The Netherlands.
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22
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Piendl SK, Geissler D, Weigelt L, Belder D. Multiple Heart-Cutting Two-Dimensional Chip-HPLC Combined with Deep-UV Fluorescence and Mass Spectrometric Detection. Anal Chem 2020; 92:3795-3803. [DOI: 10.1021/acs.analchem.9b05206] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Sebastian K. Piendl
- Institute of Analytical Chemistry, Leipzig University, Linnéstraße 3, 04103 Leipzig, Germany
| | - David Geissler
- Institute of Analytical Chemistry, Leipzig University, Linnéstraße 3, 04103 Leipzig, Germany
| | - Laura Weigelt
- Institute of Analytical Chemistry, Leipzig University, Linnéstraße 3, 04103 Leipzig, Germany
| | - Detlev Belder
- Institute of Analytical Chemistry, Leipzig University, Linnéstraße 3, 04103 Leipzig, Germany
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23
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De Vos J, Dams M, Broeckhoven K, Desmet G, Horstkotte B, Eeltink S. Prototyping of a Microfluidic Modulator Chip and Its Application in Heart-Cut Strong-Cation-Exchange-Reversed-Phase Liquid Chromatography Coupled to Nanoelectrospray Mass Spectrometry for Targeted Proteomics. Anal Chem 2020; 92:2388-2392. [DOI: 10.1021/acs.analchem.9b05141] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Jelle De Vos
- Department of Chemical Engineering, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | - Magali Dams
- Department of Chemical Engineering, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | - Ken Broeckhoven
- Department of Chemical Engineering, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | - Gert Desmet
- Department of Chemical Engineering, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | - Burkhard Horstkotte
- Department of Chemical Engineering, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
- Department of Analytical Chemistry, Faculty of Pharmacy, Charles University, Heyrovského 1203, CZ-50005 Hradec Králové, Czech Republic
| | - Sebastiaan Eeltink
- Department of Chemical Engineering, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
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24
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Mixed-mode chromatography characteristics of chiralpak ZWIX(+) and ZWIX(−) and elucidation of their chromatographic orthogonality for LC × LC application. Anal Chim Acta 2020; 1093:168-179. [DOI: 10.1016/j.aca.2019.09.068] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2019] [Revised: 09/18/2019] [Accepted: 09/22/2019] [Indexed: 12/12/2022]
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25
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Liu W, Shang X, Yao S, Wang F. A novel and nonderivatization method for the determination of valproic acid in human serum by two‐dimensional liquid chromatography. Biomed Chromatogr 2019; 34:e4695. [PMID: 31469425 DOI: 10.1002/bmc.4695] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 08/22/2019] [Accepted: 08/26/2019] [Indexed: 11/07/2022]
Affiliation(s)
- Wei Liu
- Department of PharmacyAffiliated Guangji Hospital of Soochow University Suzhou Jiangsu China
| | - Xiang Shang
- Department of PharmacyAffiliated Guangji Hospital of Soochow University Suzhou Jiangsu China
| | - Shuyong Yao
- Department of PharmacyAffiliated Guangji Hospital of Soochow University Suzhou Jiangsu China
| | - Feng Wang
- Department of Pharmacythe Second Xiangya Hospital of Central South University Changsha Hunan China
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26
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Yang P, Gao W, Zhang T, Pursch M, Luong J, Sattler W, Singh A, Backer S. Two‐dimensional liquid chromatography with active solvent modulation for studying monomer incorporation in copolymer dispersants. J Sep Sci 2019; 42:2805-2815. [DOI: 10.1002/jssc.201900283] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2019] [Revised: 06/23/2019] [Accepted: 06/24/2019] [Indexed: 12/13/2022]
Affiliation(s)
- Peilin Yang
- Analytical ScienceThe Dow Chemical Company Collegeville PA USA
| | - Wei Gao
- Analytical ScienceThe Dow Chemical Company Collegeville PA USA
| | - Tianlan Zhang
- Analytical ScienceThe Dow Chemical Company Collegeville PA USA
| | - Matthias Pursch
- Analytical ScienceDow Deutschland Anlagen GmbH Stade Germany
| | - Jim Luong
- Analytical ScienceDow Chemical Canada ULC Fort Saskatchewan AB Canada
| | - Wesley Sattler
- Formulation Science & AutomationThe Dow Chemical Company Collegeville PA USA
| | - Anurima Singh
- Packaging and Specialty PlasticsThe Dow Chemical Company Freeport TX USA
| | - Scott Backer
- Home and Personal CareThe Dow Chemical Company Collegeville PA USA
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27
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Chen Y, Li J, Schmitz OJ. Development of an At-Column Dilution Modulator for Flexible and Precise Control of Dilution Factors to Overcome Mobile Phase Incompatibility in Comprehensive Two-Dimensional Liquid Chromatography. Anal Chem 2019; 91:10251-10257. [DOI: 10.1021/acs.analchem.9b02391] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Yingzhuang Chen
- Key Laboratory of Phytochemical R&D of Hunan Province, Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research, Ministry of Education, Hunan Normal University, Changsha 410081, China
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28
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Pirok BWJ, Stoll DR, Schoenmakers PJ. Recent Developments in Two-Dimensional Liquid Chromatography: Fundamental Improvements for Practical Applications. Anal Chem 2018; 91:240-263. [PMID: 30380827 PMCID: PMC6322149 DOI: 10.1021/acs.analchem.8b04841] [Citation(s) in RCA: 197] [Impact Index Per Article: 32.8] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Bob W J Pirok
- University of Amsterdam , van 't Hoff Institute for Molecular Sciences, Analytical-Chemistry Group , Science Park 904 , 1098 XH Amsterdam , The Netherlands.,TI-COAST , Science Park 904 , 1098 XH Amsterdam , The Netherlands
| | - Dwight R Stoll
- Department of Chemistry , Gustavus Adolphus College , Saint Peter , Minnesota 56082 , United States
| | - Peter J Schoenmakers
- University of Amsterdam , van 't Hoff Institute for Molecular Sciences, Analytical-Chemistry Group , Science Park 904 , 1098 XH Amsterdam , The Netherlands
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29
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Bäurer S, Guo W, Polnick S, Lämmerhofer M. Simultaneous Separation of Water- and Fat-Soluble Vitamins by Selective Comprehensive HILIC × RPLC (High-Resolution Sampling) and Active Solvent Modulation. Chromatographia 2018. [DOI: 10.1007/s10337-018-3615-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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30
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Groeneveld G, Dunkle MN, Rinken M, Gargano AF, de Niet A, Pursch M, Mes EP, Schoenmakers PJ. Characterization of complex polyether polyols using comprehensive two-dimensional liquid chromatography hyphenated to high-resolution mass spectrometry. J Chromatogr A 2018; 1569:128-138. [DOI: 10.1016/j.chroma.2018.07.054] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 06/22/2018] [Accepted: 07/17/2018] [Indexed: 10/28/2022]
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