1
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Dhellemmes L, Leclercq L, Höchsmann A, Neusüß C, Biron JP, Roca S, Cottet H. Critical parameters for highly efficient and reproducible polyelectrolyte multilayer coatings for protein separation by capillary electrophoresis. J Chromatogr A 2023; 1695:463912. [PMID: 36972664 DOI: 10.1016/j.chroma.2023.463912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 03/01/2023] [Accepted: 03/02/2023] [Indexed: 03/08/2023]
Abstract
Since the introduction of polyelectrolyte multilayers to protein separation in capillary electrophoresis (CE), some progress has been made to improve separation efficiency by varying different parameters, such as buffer ionic strength and pH, polyelectrolyte nature and number of deposited layers. However, CE is often overlooked as it lacks robustness compared to other separation techniques. In this work, critical parameters for the construction of efficient and reproducible Successive multiple ionic-polymer layers (SMIL) coatings were investigated, focusing on experimental conditions, such as vial preparation and sample conservation which were shown to have a significant impact on separation performances. In addition to repeatability, intra- and inter-capillary precision were assessed, demonstrating the improved capability of poly(diallyldimethylammonium chloride) / poly(sodium styrene sulfonate) (PDADMAC / PSS) coated capillaries to separate model proteins in a 2 M acetic acid background electrolyte when all the correct precautions are put in place (with run to run%RSD(tm) < 1.8%, day to day%RSD(tm) < 3.2% and cap to cap%RSD(tm) < 4.6%). The approach recently introduced to calculate retention factors was used to quantify residual protein adsorption onto the capillary wall and to assess capillary coating performances. 5-layer PDADAMAC / PSS coatings led to average retention factors for the five model proteins of ∼4×10-2. These values suggest a relatively low residual protein adsorption leading to reasonably flat plate height vs linear velocity curves, obtained by performing electrophoretic separations at different electrical voltages (-10 to -25 kV).
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2
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Nanosphere size control by varying the ratio of poly(ester amide) block copolymer blends. J Colloid Interface Sci 2022; 623:247-256. [PMID: 35588632 DOI: 10.1016/j.jcis.2022.03.144] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 03/29/2022] [Accepted: 03/30/2022] [Indexed: 01/05/2023]
Abstract
HYPOTHESIS Blending amphiphilic triblock (A-B-A) and diblock (A-B) copolymers comprised of the same hydrophobic tyrosine-derived oligomeric B-block and hydrophilic poly(ethylene glycol) methyl ether (mPEG) A-block can provide highly tunable self-assembled nanosphere particle sizes suitable for biomedical applications. EXPERIMENT Triblock and diblock copolymers were synthesized via carbodiimide chemistry and were characterized by nuclear magnetic resonance (NMR) and gel permeation chromatography (GPC). The amount of free PEG present in the purified copolymers was determined using a standard addition calibration curve and GPC peak deconvolution methods. Nanospheres were prepared by co-precipitation of each copolymer and of copolymer blends over a range of mole ratios. Nanospheres were characterized by dynamic light scattering (DLS), transmission electron microscopy (TEM) and % polymer recovery post-preparation. FINDING Precise synthesis control produced triblock and diblock copolymers with narrow molecular weight distributions and minimal residual reactants. Self-assembled nanosphere particle sizes were 33 nm for the triblock and 129 nm for the diblock, and the size of their blends increased continuously as a function of mole ratio within that biomedically relevant range. Addition of unreacted PEG had minimal impact on either triblock or diblock nanosphere particle sizes whereas addition of unreacted oligomeric B-block increased nanosphere sizes.
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3
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Jiang Q, Seth S, Scharl T, Schroeder T, Jungbauer A, Dimartino S. Prediction of the performance of pre-packed purification columns through machine learning. J Sep Sci 2022; 45:1445-1457. [PMID: 35262290 PMCID: PMC9310636 DOI: 10.1002/jssc.202100864] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 01/31/2022] [Accepted: 03/01/2022] [Indexed: 11/11/2022]
Abstract
Pre-packed columns have been increasingly used in process development and biomanufacturing thanks to their ease of use and consistency. Traditionally, packing quality is predicted through rate models, which require extensive calibration efforts through independent experiments to determine relevant mass transfer and kinetic rate constants. Here we propose machine learning as a complementary predictive tool for column performance. A machine learning algorithm, extreme gradient boosting, was applied to a large data set of packing quality (plate height and asymmetry) for pre-packed columns as a function of quantitative parameters (column length, column diameter, and particle size) and qualitative attributes (backbone and functional mode). The machine learning model offered excellent predictive capabilities for the plate height and the asymmetry (90 and 93%, respectively), with packing quality strongly influenced by backbone (∼70% relative importance) and functional mode (∼15% relative importance), well above all other quantitative column parameters. The results highlight the ability of machine learning to provide reliable predictions of column performance from simple, generic parameters, including strategic qualitative parameters such as backbone and functionality, usually excluded from quantitative considerations. Our results will guide further efforts in column optimization, for example, by focusing on improvements of backbone and functional mode to obtain optimized packings.
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Affiliation(s)
- Qihao Jiang
- Institute of BioengineeringSchool of EngineeringThe University of EdinburghEdinburghUK
| | - Sohan Seth
- School of InformaticsThe University of EdinburghEdinburghUK
| | - Theresa Scharl
- Austrian Centre of Industrial BiotechnologyViennaAustria
- Institute of StatisticsUniversity of Natural Resources and Life Sciences ViennaViennaAustria
| | | | - Alois Jungbauer
- Austrian Centre of Industrial BiotechnologyViennaAustria
- Department of BiotechnologyUniversity of Natural Resources and Life SciencesViennaAustria
| | - Simone Dimartino
- Institute of BioengineeringSchool of EngineeringThe University of EdinburghEdinburghUK
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4
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Zhang M, Li J, Chen M, Pan X, Zhang Z, Zhu J. Combination of the Photoinduced Atom Transfer Radical Addition Reaction and Living Cationic Polymerization: A Latent Initiator Strategy toward Tailoring Polymer Molecular Weight Distributions. Macromolecules 2021. [DOI: 10.1021/acs.macromol.1c00332] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Mengmeng Zhang
- State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials, Department of Polymer Science and Engineering, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, China
| | - Jiajia Li
- State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials, Department of Polymer Science and Engineering, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, China
| | - Miao Chen
- State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials, Department of Polymer Science and Engineering, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, China
| | - Xiangqiang Pan
- State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials, Department of Polymer Science and Engineering, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, China
| | - Zhengbiao Zhang
- State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials, Department of Polymer Science and Engineering, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, China
| | - Jian Zhu
- State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials, Department of Polymer Science and Engineering, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, China
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5
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Netopilík M. Plate-model applied on concentration effects in size exclusion chromatography. J LIQ CHROMATOGR R T 2020. [DOI: 10.1080/10826076.2019.1703116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Miloš Netopilík
- Academy of Sciences of the Czech Republic, Institute of Macromolecular Chemistry, Prague, Czech Republic
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6
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Grabarics M, Lettow M, Kirk AT, von Helden G, Causon TJ, Pagel K. Plate-height model of ion mobility-mass spectrometry. Analyst 2020; 145:6313-6333. [DOI: 10.1039/d0an00433b] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
In analogy to chromatography, a plate-height model of drift tube ion mobility-mass spectrometry is presented that describes zone broadening and resolving power in ion mobility separations.
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Affiliation(s)
- Márkó Grabarics
- Department of Biology
- Chemistry and Pharmacy
- Institute of Chemistry and Biochemistry
- Freie Universität Berlin
- 14195 Berlin
| | - Maike Lettow
- Department of Biology
- Chemistry and Pharmacy
- Institute of Chemistry and Biochemistry
- Freie Universität Berlin
- 14195 Berlin
| | - Ansgar T. Kirk
- Institute of Electrical Engineering and Measurement Technology
- Department of Sensors and Measurement Technology
- Leibniz Universität Hannover
- 30167 Hannover
- Germany
| | - Gert von Helden
- Fritz Haber Institute of the Max Planck Society
- Department of Molecular Physics
- 14195 Berlin
- Germany
| | - Tim J. Causon
- Department of Chemistry
- Institute of Analytical Chemistry
- University of Natural Resources and Life Sciences
- Vienna
- 1190 Vienna
| | - Kevin Pagel
- Department of Biology
- Chemistry and Pharmacy
- Institute of Chemistry and Biochemistry
- Freie Universität Berlin
- 14195 Berlin
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7
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Sifri RJ, Padilla-Vélez O, Coates GW, Fors BP. Controlling the Shape of Molecular Weight Distributions in Coordination Polymerization and Its Impact on Physical Properties. J Am Chem Soc 2019; 142:1443-1448. [DOI: 10.1021/jacs.9b11462] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Renee J. Sifri
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853-1301, United States
| | - Omar Padilla-Vélez
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853-1301, United States
| | - Geoffrey W. Coates
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853-1301, United States
| | - Brett P. Fors
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853-1301, United States
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8
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Broeckhoven K, Desmet G. Advances and Challenges in Extremely High-Pressure Liquid Chromatography in Current and Future Analytical Scale Column Formats. Anal Chem 2019; 92:554-560. [DOI: 10.1021/acs.analchem.9b04278] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Ken Broeckhoven
- Vrije Universiteit Brussel, Department of Chemical Engineering (CHIS), Faculty of Engineering, Pleinlaan 2, 1050 Brussels, Belgium
| | - Gert Desmet
- Vrije Universiteit Brussel, Department of Chemical Engineering (CHIS), Faculty of Engineering, Pleinlaan 2, 1050 Brussels, Belgium
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9
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Whitfield R, Truong NP, Messmer D, Parkatzidis K, Rolland M, Anastasaki A. Tailoring polymer dispersity and shape of molecular weight distributions: methods and applications. Chem Sci 2019; 10:8724-8734. [PMID: 33552458 PMCID: PMC7844732 DOI: 10.1039/c9sc03546j] [Citation(s) in RCA: 99] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 08/27/2019] [Indexed: 01/08/2023] Open
Abstract
The width and shape of molecular weight distributions can significantly affect the properties of polymeric materials and thus are key parameters to control. This mini-review aims to critically summarise recent approaches developed to tailor molecular weight distributions and highlights the strengths and limitations of each technique. Special emphasis will also be given to applications where tuning the molecular weight distribution has been used as a strategy to not only enhance polymer properties but also to increase the fundamental understanding behind complex mechanisms and phenomena.
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Affiliation(s)
- Richard Whitfield
- Laboratory of Polymeric Materials , Department of Materials , ETH Zurich , Vladimir-Prelog-Weg 5 , Zurich 8093 , Switzerland .
| | - Nghia P Truong
- Laboratory of Polymeric Materials , Department of Materials , ETH Zurich , Vladimir-Prelog-Weg 5 , Zurich 8093 , Switzerland .
| | - Daniel Messmer
- Laboratory of Polymeric Materials , Department of Materials , ETH Zurich , Vladimir-Prelog-Weg 5 , Zurich 8093 , Switzerland .
| | - Kostas Parkatzidis
- Laboratory of Polymeric Materials , Department of Materials , ETH Zurich , Vladimir-Prelog-Weg 5 , Zurich 8093 , Switzerland .
| | - Manon Rolland
- Laboratory of Polymeric Materials , Department of Materials , ETH Zurich , Vladimir-Prelog-Weg 5 , Zurich 8093 , Switzerland .
| | - Athina Anastasaki
- Laboratory of Polymeric Materials , Department of Materials , ETH Zurich , Vladimir-Prelog-Weg 5 , Zurich 8093 , Switzerland .
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10
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Desmet G, Broeckhoven K. Extra-column band broadening effects in contemporary liquid chromatography: Causes and solutions. Trends Analyt Chem 2019. [DOI: 10.1016/j.trac.2019.115619] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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11
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Kuroda I, Uzu H, Miyazaki S, Ohira M, Tanaka N. Reduction of the extra-column band dispersion by a slow transport of a sample band from the injector to the column in isocratic reversed-phase liquid chromatography. J Chromatogr A 2018; 1572:44-53. [DOI: 10.1016/j.chroma.2018.08.037] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 08/03/2018] [Accepted: 08/15/2018] [Indexed: 01/01/2023]
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12
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Numerical correction for asymmetrical peak profiles for moment analysis of chromatographic behavior. J Chromatogr A 2018; 1567:155-163. [DOI: 10.1016/j.chroma.2018.06.067] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 06/18/2018] [Accepted: 06/28/2018] [Indexed: 11/21/2022]
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13
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Deridder S, Desmet G, Broeckhoven K. Numerical investigation of band spreading generated by flow-through needle and fixed loop sample injectors. J Chromatogr A 2018; 1552:29-42. [DOI: 10.1016/j.chroma.2018.04.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Revised: 03/30/2018] [Accepted: 04/01/2018] [Indexed: 02/06/2023]
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14
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Gentekos DT, Jia J, Tirado ES, Barteau KP, Smilgies DM, DiStasio RA, Fors BP. Exploiting Molecular Weight Distribution Shape to Tune Domain Spacing in Block Copolymer Thin Films. J Am Chem Soc 2018. [DOI: 10.1021/jacs.8b00694] [Citation(s) in RCA: 78] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- Dillon T. Gentekos
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Junteng Jia
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Erika S. Tirado
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Katherine P. Barteau
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States
| | - Detlef-M. Smilgies
- Cornell High Energy Synchrotron Source (CHESS), Cornell University, Ithaca, New York 14853, United States
| | - Robert A. DiStasio
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Brett P. Fors
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
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15
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Broeckhoven K, Vanderlinden K, Guillarme D, Desmet G. On-tubing fluorescence measurements of the band broadening of contemporary injectors in ultra-high performance liquid chromatography. J Chromatogr A 2018; 1535:44-54. [DOI: 10.1016/j.chroma.2017.12.032] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Revised: 12/08/2017] [Accepted: 12/12/2017] [Indexed: 10/18/2022]
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16
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Nadgorny M, Gentekos DT, Xiao Z, Singleton SP, Fors BP, Connal LA. Manipulation of Molecular Weight Distribution Shape as a New Strategy to Control Processing Parameters. Macromol Rapid Commun 2017; 38. [DOI: 10.1002/marc.201700352] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Revised: 06/28/2017] [Indexed: 11/11/2022]
Affiliation(s)
- Milena Nadgorny
- The Department of Chemical and Biomolecular EngineeringThe University of Melbourne Victoria 3010 Australia
| | - Dillon T. Gentekos
- Department of Chemistry and Chemical BiologyCornell University Ithaca NY 14853 USA
| | - Zeyun Xiao
- The Department of Chemical and Biomolecular EngineeringThe University of Melbourne Victoria 3010 Australia
| | - S. Parker Singleton
- Department of Chemistry and Chemical BiologyCornell University Ithaca NY 14853 USA
| | - Brett P. Fors
- Department of Chemistry and Chemical BiologyCornell University Ithaca NY 14853 USA
| | - Luke A. Connal
- The Department of Chemical and Biomolecular EngineeringThe University of Melbourne Victoria 3010 Australia
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17
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Peris-Díaz MD, Alcoriza-Balaguer MI, García-Cañaveras JC, Santonja F, Sentandreu E, Lahoz A. RpeakChrom: Novel R package for the automated characterization and optimization of column efficiency in high-performance liquid chromatography analysis. Electrophoresis 2017; 38:2985-2995. [PMID: 28665035 DOI: 10.1002/elps.201700180] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Revised: 06/08/2017] [Accepted: 06/14/2017] [Indexed: 11/07/2022]
Abstract
Characterization of chromatographic columns using the traditional van Deemter method is limited by the necessity of calculating extra-column variance, issue particularly relevant when modeling asymmetrical peaks eluted from monolithic columns. A novel R package that implements Parabolic Variance Modified Gaussian approach for accurate peak modeling, van Deemter equation and two alternatives approaches, based on van Deemter, has been developed to calculate the height equivalent to a theoretical plate (HETP). To assess package capabilities conventional packed reverse-phase and monolithic HPLC columns were characterized. Peaks eluted from the monolithic column showed a high value of factor asymmetry due, in part, to the contribution of extra-column factors. Such deviation can be circumvented by the two alternatives approaches implemented in the R-package. Furthermore, increased values of eddy diffusion and mass transfer kinetics terms in HETP were observed for the packed column, while accuracy was below 9% in all cases. These results showed the usefulness of the R-package for both modeling chromatographic peaks and assessing column efficiency. The RpeakChrom package could become a helpful tool for testing new stationary phases during column development and to evaluate column during its lifetime. This R tool is freely available from CRAN (https://CRAN.R-project.org/package=RpeakChrom).
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Affiliation(s)
- Manuel David Peris-Díaz
- Biomarkers and Precision Medicine Unit, Analytical Unit, Instituto de Investigación Sanitaria, Fundación Hospital La Fe, Valencia, Spain
| | - Maria Isabel Alcoriza-Balaguer
- Biomarkers and Precision Medicine Unit, Analytical Unit, Instituto de Investigación Sanitaria, Fundación Hospital La Fe, Valencia, Spain
| | - Juan Carlos García-Cañaveras
- Biomarkers and Precision Medicine Unit, Analytical Unit, Instituto de Investigación Sanitaria, Fundación Hospital La Fe, Valencia, Spain
| | - Francisco Santonja
- Departamento de Estadística e Investigación Operativa, Facultat de Ciencias Matematicas, Universidad de Valencia, Burjassot, Spain
| | - Enrique Sentandreu
- Biomarkers and Precision Medicine Unit, Analytical Unit, Instituto de Investigación Sanitaria, Fundación Hospital La Fe, Valencia, Spain
| | - Agustín Lahoz
- Biomarkers and Precision Medicine Unit, Analytical Unit, Instituto de Investigación Sanitaria, Fundación Hospital La Fe, Valencia, Spain
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18
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Mao K, Du H, Bai L, Zhang Y, Zhu H, Wang Y. Poly (2-methyl-2-oxazoline) coating by thermally induced immobilization for determination of bovine lactoferrin in infant formula with capillary electrophoresis. Talanta 2017; 168:230-239. [DOI: 10.1016/j.talanta.2017.03.051] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2016] [Revised: 03/10/2017] [Accepted: 03/16/2017] [Indexed: 11/16/2022]
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19
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Schultze-Jena A, Boon M, Bussmann P, Janssen A, van der Padt A. The counterintuitive role of extra-column volume in the determination of column efficiency and scaling of chromatographic processes. J Chromatogr A 2017; 1493:49-56. [DOI: 10.1016/j.chroma.2017.02.068] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Revised: 02/17/2017] [Accepted: 02/28/2017] [Indexed: 01/28/2023]
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20
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Schure MR, Moran RE. Size exclusion chromatography with superficially porous particles. J Chromatogr A 2017; 1480:11-19. [PMID: 28007299 PMCID: PMC5266604 DOI: 10.1016/j.chroma.2016.12.016] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2016] [Revised: 11/07/2016] [Accepted: 12/09/2016] [Indexed: 10/20/2022]
Abstract
A comparison is made using size-exclusion chromatography (SEC) of synthetic polymers between fully porous particles (FPPs) and superficially porous particles (SPPs) with similar particle diameters, pore sizes and equal flow rates. Polystyrene molecular weight standards with a mobile phase of tetrahydrofuran are utilized for all measurements conducted with standard HPLC equipment. Although it is traditionally thought that larger pore volume is thermodynamically advantageous in SEC for better separations, SPPs have kinetic advantages and these will be shown to compensate for the loss in pore volume compared to FPPs. The comparison metrics include the elution range (smaller with SPPs), the plate count (larger for SPPs), the rate production of theoretical plates (larger for SPPs) and the specific resolution (larger with FPPs). Advantages to using SPPs for SEC are discussed such that similar separations can be conducted faster using SPPs. SEC using SPPs offers similar peak capacities to that using FPPs but with faster operation. This also suggests that SEC conducted in the second dimension of a two-dimensional liquid chromatograph may benefit with reduced run time and with equivalently reduced peak width making SPPs advantageous for sampling the first dimension by the second dimension separator. Additional advantages are discussed for biomolecules along with a discussion of optimization criteria for size-based separations.
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Affiliation(s)
- Mark R Schure
- Theoretical Separation Science Laboratory, Kroungold Analytical, Inc., 1299 Butler Pike, Blue Bell, PA, 19422 USA.
| | - Robert E Moran
- Advanced Materials Technology, Inc., 3521 Silverside Road, Suite 1-K, Quillen Building, Wilmington, DE, 19810, USA
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21
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Liu H, Pang Z, Fan G. Translation Modification Iteration for Resolution and Quantification of Overlapping Chromatographic Peaks. Chromatographia 2016. [DOI: 10.1007/s10337-016-3172-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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22
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Scharl T, Jungreuthmayer C, Dürauer A, Schweiger S, Schröder T, Jungbauer A. Trend analysis of performance parameters of pre-packed columns for protein chromatography over a time span of ten years. J Chromatogr A 2016; 1465:63-70. [DOI: 10.1016/j.chroma.2016.07.054] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Revised: 07/17/2016] [Accepted: 07/20/2016] [Indexed: 11/29/2022]
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23
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Kottisch V, Gentekos DT, Fors BP. "Shaping" the Future of Molecular Weight Distributions in Anionic Polymerization. ACS Macro Lett 2016; 5:796-800. [PMID: 35614766 DOI: 10.1021/acsmacrolett.6b00392] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Varying molecular weight distributions (MWDs) have the potential to precisely tune polymer properties, but this approach remains relatively unexplored owing to a lack of synthetic methods that provide control over the exact makeup of a distribution. Herein, we report a simple and highly efficient strategy for addressing this challenge through temporal regulation of initiation in the anionic polymerization of styrene. This method yields unprecedented control over the shape of the polymer MWD and facilitates the synthesis of diblock copolymers with controlled MWD compositions. Importantly, we show that the MWD symmetry has a marked influence on the stiffness of poly(styrene-block-isoprene) copolymers, which demonstrates that varying MWD shape is an effective method for altering polymer properties.
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Affiliation(s)
| | | | - Brett P. Fors
- Cornell University, Ithaca, New York 14853, United States
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24
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Vanderheyden Y, Vanderlinden K, Broeckhoven K, Desmet G. Problems involving the determination of the column-only band broadening in columns producing narrow and tailed peaks. J Chromatogr A 2016; 1440:74-84. [DOI: 10.1016/j.chroma.2016.02.042] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Revised: 02/12/2016] [Accepted: 02/15/2016] [Indexed: 10/22/2022]
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25
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Gentekos DT, Dupuis LN, Fors BP. Beyond Dispersity: Deterministic Control of Polymer Molecular Weight Distribution. J Am Chem Soc 2016; 138:1848-51. [DOI: 10.1021/jacs.5b13565] [Citation(s) in RCA: 123] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | | | - Brett P. Fors
- Cornell University, Ithaca, New York 14853, United States
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26
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Prediction of Peak Shape and Characterization of Column Performance in Liquid Chromatography as a Function of Flow Rate. CHROMATOGRAPHY 2015. [DOI: 10.3390/chromatography2040625] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Chen G, Svirskis D, Wen J. Development and validation of a stability indicating isocratic HPLC method for gemcitabine with application to drug release from poly lactic-co-glycolic acid nanoparticles and enzymatic degradation studies. J Pharm Pharmacol 2015; 67:1528-36. [DOI: 10.1111/jphp.12470] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Accepted: 06/21/2015] [Indexed: 11/28/2022]
Abstract
Abstract
Objectives
Previously reported HPLC methods for gemcitabine determination are time-consuming with complicated mobile phases and gradient elution. Thus, a sensitive and stability-indicating isocratic HPLC method, which provides simple, fast and precise measurements, was developed. This method was applied to study the digestive enzymatic degradation of gemcitabine, for the first time, and the protection afforded following incorporation into poly lactic-co-glycolic acid (PLGA) nanoparticles.
Methods
An analytical HPLC method was developed with an optimized combination of operating conditions. Forced degradation and application of the method to in-vitro drug release studies were conducted. Finally, gemcitabine-loaded nanoparticles were exposed to the digestive enzymes pepsin, trypsin and α-chymotrypsin, and the resulting degradation evaluated.
Key findings
The analytical method was linear between 1 and 100 μg/ml, with excellent accuracy of 99.91–101.77% and precision of 1.71 or lower, with a 0.014 μg/ml limit of detection (LOD) and a 0.043 μg/ml limit of quantification (LOQ). Following exposure of gemcitabine to stressors, the drug was relatively stable in strong acid (1 N HCl), base (1 N NaOH) and as an aqueous solution exposed to light over 7 days, with less than 10% degradation. However, gemcitabine was more susceptible to degradation at 70°C and oxidative conditions (3% v/v H2O2) with greater than 10% degradation noted after 7 days. In-vitro drug release studies demonstrated a sustained drug release profile from PLGA nanoparticles, which also improved the resistance of gemcitabine to enzymatic degradation.
Conclusion
These results demonstrate the utility and effectiveness of this simple isocratic HPLC method in evaluating the overall performance of a gemcitabine-loaded formulation.
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Affiliation(s)
- Guanyu Chen
- School of Pharmacy, Faculty of Medical and Health Science, University of Auckland, Aukland, New Zealand
| | - Darren Svirskis
- School of Pharmacy, Faculty of Medical and Health Science, University of Auckland, Aukland, New Zealand
| | - Jingyuan Wen
- School of Pharmacy, Faculty of Medical and Health Science, University of Auckland, Aukland, New Zealand
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Analysis of therapeutic proteins and peptides using multiangle light scattering coupled to ultra high performance liquid chromatography. J Sep Sci 2015; 38:1537-43. [DOI: 10.1002/jssc.201400863] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Revised: 01/30/2015] [Accepted: 02/08/2015] [Indexed: 01/28/2023]
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29
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Hu D, Mei X, Shi P, Zhou X. Inner-Pipe Structure to Improve Column Heterogeneity and Peak Shape. J Chromatogr Sci 2015; 53:565-70. [DOI: 10.1093/chromsci/bmu085] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Flow rate dependent extra-column variance from injection in capillary liquid chromatography. J Chromatogr A 2014; 1380:38-44. [PMID: 25591400 DOI: 10.1016/j.chroma.2014.12.017] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Revised: 11/14/2014] [Accepted: 12/05/2014] [Indexed: 11/20/2022]
Abstract
Efficiency and resolution in capillary liquid chromatography (LC) can be significantly affected by extra-column band broadening, especially for isocratic separations. This is particularly a concern in evaluating column bed structure using non-retained test compounds. The band broadening due to an injector supplied with a commercially available capillary LC system was characterized from experimental measurements. The extra-column variance from the injection valve was found to have an extra-column contribution independent of the injection volume, showing an exponential dependence on flow rate. The overall extra-column variance from the injection valve was found to vary from 34 to 23 nL. A new mathematical model was derived that explains this exponential contribution of extra-column variance on chromatographic performance. The chromatographic efficiency was compromised by ∼130% for a non-retained analyte because of injection valve dead volume. The measured chromatographic efficiency was greatly improved when a new nano-flow pumping system with integrated injection valve was used.
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31
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Comparison and optimization of different peak integration methods to determine the variance of unretained and extra-column peaks. J Chromatogr A 2014; 1364:140-50. [DOI: 10.1016/j.chroma.2014.08.066] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Revised: 08/19/2014] [Accepted: 08/21/2014] [Indexed: 11/19/2022]
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32
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Zou X, Gao M, Liu D, Zhang X, Xiu Z, Xiao H. A novel preparative liquid chromatograph for repetitive enrichment and purification of low-abundance compounds. J Chromatogr A 2014; 1351:90-5. [DOI: 10.1016/j.chroma.2014.05.041] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2014] [Revised: 05/13/2014] [Accepted: 05/15/2014] [Indexed: 11/16/2022]
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33
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Fekete S, Kohler I, Rudaz S, Guillarme D. Importance of instrumentation for fast liquid chromatography in pharmaceutical analysis. J Pharm Biomed Anal 2014; 87:105-19. [DOI: 10.1016/j.jpba.2013.03.012] [Citation(s) in RCA: 96] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Accepted: 03/16/2013] [Indexed: 11/25/2022]
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34
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Cabooter D, Broeckhoven K, Sterken R, Vanmessen A, Vandendael I, Nakanishi K, Deridder S, Desmet G. Detailed characterization of the kinetic performance of first and second generation silica monolithic columns for reversed-phase chromatography separations. J Chromatogr A 2014; 1325:72-82. [DOI: 10.1016/j.chroma.2013.11.047] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Revised: 11/20/2013] [Accepted: 11/26/2013] [Indexed: 12/15/2022]
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35
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Spaggiari D, Fekete S, Eugster PJ, Veuthey JL, Geiser L, Rudaz S, Guillarme D. Contribution of various types of liquid chromatography–mass spectrometry instruments to band broadening in fast analysis. J Chromatogr A 2013; 1310:45-55. [DOI: 10.1016/j.chroma.2013.08.001] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Revised: 07/31/2013] [Accepted: 08/02/2013] [Indexed: 10/26/2022]
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36
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Kirkland JJ, Schuster SA, Johnson WL, Boyes BE. Fused-core particle technology in high-performance liquid chromatography: An overview. J Pharm Anal 2013; 3:303-312. [PMID: 29403832 PMCID: PMC5760966 DOI: 10.1016/j.jpha.2013.02.005] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The advent of superficially porous particles (SPPs) for packed HPLC columns has changed the way that many practitioners have approached the problem of developing needed separations. The very high efficiency of such columns, combined with convenient operating conditions, modest back pressures and the ability to use conventional HPLC instruments has resulted in intense basic studies of SPP technology, and widespread applications in many sciences. This report contains an overview of the SPP technology first developed in 2006 by Advanced Materials Technology, Inc., for sub-3-μm particles, then expanded into a family of SPP products with different particle sizes, pore sizes and other physical parameters. This approach was designed so that each particle of the family could be optimized for separating a particular group of compounds, usually based on solute size.
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Affiliation(s)
- Joseph J Kirkland
- Advanced Materials Technology, Inc., 3521 Silverside Road, Suite 1-K, Quillen Building, Wilmington, DE 19810, USA
| | - Stephanie A Schuster
- Advanced Materials Technology, Inc., 3521 Silverside Road, Suite 1-K, Quillen Building, Wilmington, DE 19810, USA
| | - William L Johnson
- Advanced Materials Technology, Inc., 3521 Silverside Road, Suite 1-K, Quillen Building, Wilmington, DE 19810, USA
| | - Barry E Boyes
- Advanced Materials Technology, Inc., 3521 Silverside Road, Suite 1-K, Quillen Building, Wilmington, DE 19810, USA.,Complex Carbohydrate Research Center, 315 Riverbend Road, Athens, GA 30602, USA
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37
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Hong P, Koza S, Bouvier ESP. Size-Exclusion Chromatography for the Analysis of Protein Biotherapeutics and their Aggregates. J LIQ CHROMATOGR R T 2012; 35:2923-2950. [PMID: 23378719 PMCID: PMC3556795 DOI: 10.1080/10826076.2012.743724] [Citation(s) in RCA: 299] [Impact Index Per Article: 24.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
In recent years, the use and number of biotherapeutics has increased significantly. For these largely protein-based therapies, the quantitation of aggregates is of particular concern given their potential effect on efficacy and immunogenicity. This need has renewed interest in size-exclusion chromatography (SEC). In the following review we will outline the history and background of SEC for the analysis of proteins. We will also discuss the instrumentation for these analyses, including the use of different types of detectors. Method development for protein analysis by SEC will also be outlined, including the effect of mobile phase and column parameters (column length, pore size). We will also review some of the applications of this mode of separation that are of particular importance to protein biopharmaceutical development and highlight some considerations in their implementation.
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38
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Wu N, Bradley AC. Effect of column dimension on observed column efficiency in very high pressure liquid chromatography. J Chromatogr A 2012; 1261:113-20. [DOI: 10.1016/j.chroma.2012.05.054] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2012] [Revised: 05/13/2012] [Accepted: 05/15/2012] [Indexed: 10/28/2022]
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Blanco Gomis D, Núñez NS, García EA, Abrodo PA, Álvarez DG. Modification of a Conventional High Performance Liquid Chromatograph for Use in High Speed Liquid Chromatography. J LIQ CHROMATOGR R T 2011. [DOI: 10.1080/10826070600757623] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Domingo Blanco Gomis
- a Department of Physical and Analytical Chemistry , University of Oviedo , Oviedo , Spain
| | - Noé Sánchez Núñez
- a Department of Physical and Analytical Chemistry , University of Oviedo , Oviedo , Spain
| | - Elena Andrés García
- a Department of Physical and Analytical Chemistry , University of Oviedo , Oviedo , Spain
| | - Pilar Arias Abrodo
- a Department of Physical and Analytical Chemistry , University of Oviedo , Oviedo , Spain
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40
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Gritti F, Guiochon G. Accurate measurements of peak variances: Importance of this accuracy in the determination of the true corrected plate heights of chromatographic columns. J Chromatogr A 2011; 1218:4452-61. [DOI: 10.1016/j.chroma.2011.05.035] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2010] [Revised: 01/24/2011] [Accepted: 05/10/2011] [Indexed: 10/18/2022]
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41
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Miyabe K, Guiochon G. Numerical Method for the Estimation of Column Radial Heterogeneity and of the Actual Column Efficiency from Tailing Peak Profiles. Anal Chem 2010; 83:182-92. [DOI: 10.1021/ac102195x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Kanji Miyabe
- Graduate School of Science and Engineering for Research, University of Toyama, 3190, Gofuku, Toyama 930-8555, Japan, and Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996-1600, United States
| | - Georges Guiochon
- Graduate School of Science and Engineering for Research, University of Toyama, 3190, Gofuku, Toyama 930-8555, Japan, and Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996-1600, United States
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42
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Richard DJ, Striegel AM. The obstruction factor in size-exclusion chromatography. 1. The intraparticle obstruction factor. J Chromatogr A 2010; 1217:7131-7. [DOI: 10.1016/j.chroma.2010.09.021] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2010] [Revised: 08/27/2010] [Accepted: 09/08/2010] [Indexed: 11/30/2022]
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43
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Development and optimization of a metabolomic method for analysis of adherent cell cultures. Anal Biochem 2010; 404:30-9. [DOI: 10.1016/j.ab.2010.04.013] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2010] [Revised: 04/09/2010] [Accepted: 04/12/2010] [Indexed: 12/29/2022]
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44
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Vangelooven J, De Malsche W, Op De Beeck J, Eghbali H, Gardeniers H, Desmet G. Design and evaluation of flow distributors for microfabricated pillar array columns. LAB ON A CHIP 2010; 10:349-356. [PMID: 20091007 DOI: 10.1039/b916126k] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Five different flow distributors have been compared as a function of the flow rate for their ability to distribute small sample volumes over the entire width of flat rectangular microfabricated pillar array columns. The investigated designs can be divided in two major categories: (1) bifurcating, radially non-interconnecting distributors and (2) radially interconnecting distributors consisting of diamond-shaped pillars, elongated in the direction perpendicular to the flow, providing a high ratio of radial permeability over axial permeability. The quality of the flow distribution was evaluated experimentally by injecting equal volumes of fluorescent tracer into each of the tested designs and calculating the obtained peak variances using the method of moments. Purely bifurcating distributors perform less well than the best possible radially interconnected distributors, because the former inevitably require the use of wide open channels (d > 10 microm), wherein a lot of band broadening can occur. By doubling the aspect ratio of the radially stretched pillars from 5 to 10, the measured peak variance drops to 1/8 of the original value. The best results were obtained with a distributor in which the flow is distributed by a bed of anisotropic pillars with an aspect ratio of 10, but our results indicate that a substantial improvement can still be made by increasing the aspect ratio and adding gradually diverging sidewalls to the inlet.
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Affiliation(s)
- Joris Vangelooven
- Department of Chemical Engineering, Vrije Universiteit Brussel, Pleinlaan2, 1040 Brussels, Belgium
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45
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Miyabe K, Matsumoto Y, Niwa Y, Ando N, Guiochon G. An estimation of the column efficiency made by analyzing tailing peak profiles. J Chromatogr A 2009; 1216:8319-30. [DOI: 10.1016/j.chroma.2009.09.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2008] [Revised: 08/26/2009] [Accepted: 09/07/2009] [Indexed: 11/15/2022]
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46
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Lin SC, Whang CW. Capillary electrophoretic separation of tricyclic antidepressants using a polymer-coated capillary and β-cyclodextrin as an electrolyte additive. J Sep Sci 2008; 31:3921-9. [DOI: 10.1002/jssc.200800426] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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47
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Usher KM, Simmons CR, Dorsey JG. Modeling chromatographic dispersion: A comparison of popular equations. J Chromatogr A 2008; 1200:122-8. [DOI: 10.1016/j.chroma.2008.05.073] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2007] [Revised: 05/14/2008] [Accepted: 05/19/2008] [Indexed: 10/22/2022]
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48
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Štulík K, Pacáková V, Fleet B. Electrochemical Detection in Hight-Performance Liquid Chromatography. ACTA ACUST UNITED AC 2008. [DOI: 10.1080/10408348408542774] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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49
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Lin PYT, Bulawa HC, Wong P, Lin L, Scott J, Blank CL. The Determination of Catecholamines, Indoleamines, Metabolites, and Related Enzymatic Activities Using Three Micron Liquid Chromatography Columns. ACTA ACUST UNITED AC 2006. [DOI: 10.1080/01483918408073983] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- P. Y. T. Lin
- a Department of Chemistry , University of Oklahoma , Norman , OK , 73019
| | - H. C. Bulawa
- a Department of Chemistry , University of Oklahoma , Norman , OK , 73019
| | - P. Wong
- a Department of Chemistry , University of Oklahoma , Norman , OK , 73019
| | - L. Lin
- a Department of Chemistry , University of Oklahoma , Norman , OK , 73019
| | - J. Scott
- a Department of Chemistry , University of Oklahoma , Norman , OK , 73019
| | - C. L. Blank
- a Department of Chemistry , University of Oklahoma , Norman , OK , 73019
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