1
|
Retention and mass transfer properties of the series of unbonded, amide-bonded, and alkylsulfobetaine-bonded ethylene bridged hybrid hydrophilic interaction liquid chromatography columns. J Chromatogr A 2023; 1692:463828. [PMID: 36804802 DOI: 10.1016/j.chroma.2023.463828] [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: 12/07/2022] [Revised: 01/23/2023] [Accepted: 01/24/2023] [Indexed: 02/09/2023]
Abstract
This work investigates the link between the retentivity and the stationary phase to mobile phase mass transfer resistance of hydrophilic interaction liquid chromatography (HILIC) columns packed with the same base ethylene-bridged hybrid particles (BEH). The retention volumes, the plate heights, and the volume of the adsorbed water layer were measured for the ACQUITYTM UPLCTM BEHTM 130 Å HILIC Column (unbonded BEH), ACQUITY UPLC BEH 130 Å Amide Column (amide group attached), and AtlantisTM Premier BEH 95 Å Z-HILIC (zwitterionic group attached) Column. The method of Guo (toluene retention volumes in pure acetonitrile and in the HILIC eluent) was validated from the UNIFAC group-contribution method and applied to measure accurately the water layer volumes in these columns. A strong correlation was found between the retention volumes of most neutral polar analytes and the volume of the water layer adsorbed in the HILIC column. The fraction of the pore volume occupied by the water layer increases significantly from the BEH HILIC Column to the BEH Amide Column, and to the BEH Z-HILIC Column. This is explained by the water solvation of the attached ligands in the pore volume of the BEH Particles and to the smaller average mesopore size of the BEH Z-HILIC Particles. A second and strong correlation is also observed between the water content in the HILIC particle and the stationary phase to mobile phase mass transfer resistance of the HILIC columns at high mobile phase linear velocities. The measured intra-particle diffusivity normalized to the bulk diffusion coefficient decreased from 0.33 (BEH HILIC Column) to 0.10 (BEH Amide Column) and to only 0.03 (BEH Z-HILIC Column) for comparable retention of cytosine. These results are fully consistent with the higher viscosity of the internal eluent (higher water content) and higher internal obstruction for diffusion (smaller mesopores and internal porosity) in the BEH Z-HILIC Particles. Still, in gradient elution mode, the peak capacity was found to be 18% higher for the BEH Z-HILIC Column than that on the BEH Amide Column because the retention factors at elution were smaller when maintaining the same analysis time and starting eluent composition.
Collapse
|
2
|
Januarius T, Desmet G, Broeckhoven K. Measurement of the molecular diffusion coefficient and the effective longitudinal diffusion under supercritical fluid chromatography conditions in packed bed columns. J Chromatogr A 2022; 1682:463485. [PMID: 36182682 DOI: 10.1016/j.chroma.2022.463485] [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: 07/22/2022] [Revised: 09/02/2022] [Accepted: 09/05/2022] [Indexed: 10/14/2022]
Abstract
The improvement of supercritical fluid chromatography (SFC) instrumentation enhanced its reliability and utility over the past decade. The further development of high speed and high resolution separations is however obstructed by the lack of accurate models for axial dispersion in SFC. This work is a first step to tackle this by developing more reliable methods to measure molecular (Dmol) and longitudinal diffusion (Deff) in SFC, as these affect all aspects of separation efficiency. In the present contribution, we report on an improved method, to enable more flexible, reliable and accurate measurements of Dmol in SFC using commercial instrumentation. A two-column variant of the stopped-flow experiment is proposed as an adapted set-up for measuring the effective longitudinal diffusion coefficient Deff in SFC-conditions. Using the set-ups for a number of test-compounds, it has been found that Deff, and the coefficients describing its constituent sub-processes (cf. particle diffusion Dpart and surface diffusion γsDs), all vary in a linearly proportional way with the bulk diffusion coefficient Dmol within a high degree of accuracy. It has also been found that Deff decreases much more sharply with increasing retention factor compared to LC. By applying the effective medium theory, it was found that the relative surface diffusion coefficient γsDs/Dmol decreases strongly with retention factor for the investigated solutes and column, in contrary to what is typically observed in reversed phase liquid chromatography. Results indicate that this might be related to a change in retention behavior of the analytes. Obviously, more analytes and conditions need to be explored to complete this picture and the extend range of applicability of these observations.
Collapse
Affiliation(s)
| | - Gert Desmet
- Vrije Universiteit Brussel, Pleinlaan 2, Brussel 1050, Belgium
| | - Ken Broeckhoven
- Vrije Universiteit Brussel, Pleinlaan 2, Brussel 1050, Belgium.
| |
Collapse
|
3
|
Pepermans V, Januarius T, Desmet G, Broeckhoven K. Diffusion coefficients of an extensive set of pharmaceutical compounds in supercritical fluid chromatography over a wide range of mobile phase compositions. J Chromatogr A 2022; 1678:463327. [PMID: 35872536 DOI: 10.1016/j.chroma.2022.463327] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 07/08/2022] [Accepted: 07/08/2022] [Indexed: 10/17/2022]
Abstract
Diffusion data are essential for adequate analysis of the kinetic separation performance of any chromatographic system. Unfortunately, for Supercritical Fluid Chromatography (SFC), very little data is available of the diffusion coefficients in mobile phases typically used in contemporary methods, i.e. with a non-negligible amount of polar modifier such as methanol. In this work, a relative simple method which only requires minor modifications to a standard commercially available SFC instrument is used to determine the diffusion coefficient of an extensive set of pharmaceutical compounds in the range of 10-50 vol% of modifier (methanol) in CO2. By using a traditional SFC column, the solute is first separated from the sample solvent plug, before entering a long capillary, where the band broadening can be linked to its diffusion coefficient using the Taylor-Aris equation. By using two UV-detectors, before and after the capillary, the effect of the dispersion in the column can be eliminated and the true volumetric flow rate determined. It was found that in the investigated range of conditions, the change in mobile phase viscosity in a first approximation allows to predict the variation in diffusion coefficient. Chemical structure and more particularly functional groups can however have a significant effect on the diffusion coefficient.
Collapse
Affiliation(s)
| | | | - Gert Desmet
- Vrije Universiteit Brussel, Pleinlaan 2, Brussel 1050, Belgium
| | - Ken Broeckhoven
- Vrije Universiteit Brussel, Pleinlaan 2, Brussel 1050, Belgium.
| |
Collapse
|
4
|
Sadriaj D, Desmet G, Cabooter D. Taylor-Aris methodology for the experimental determination of molecular diffusion coefficients: Tutorial with focus on large biomolecules. J Chromatogr A 2021; 1664:462787. [PMID: 35033789 DOI: 10.1016/j.chroma.2021.462787] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 12/23/2021] [Accepted: 12/23/2021] [Indexed: 10/19/2022]
Abstract
High-Performance Liquid Chromatography (HPLC) is a key technique in the evaluation of biopharmaceuticals. To improve the separation of biopharmaceuticals, it is crucial to improve the fundamental understanding of the parameters governing their band broadening behavior. This can be obtained by a detailed assessment of the individual contributions to their mass transfer. For this purpose, a precise knowledge of the molecular diffusion coefficient (Dm) of biopharmaceuticals is required. Only little experimental data is available for the Dm-values of biopharmaceuticals under HPLC relevant conditions. Furthermore, none of the available equations that can be used to calculate Dm-values, allows to account for any conformational changes that might occur. The Taylor-Aris method is a very simple and absolute method that is often employed to determine Dm-coefficients. The Taylor-Aris method measures the band broadening of an analyte in an open tube under laminar conditions, wherein (1) longitudinal diffusion can be ignored, (2) the sample is fully radially equilibrated and (3) the contribution of the extra-column variance to the total variance is negligible. Moreover, since the open tubes are typically coiled for practical reasons, (4) the influence of secondary flows on the band broadening should be insignificant. In this tutorial paper, the impact of the four conditions mentioned above on the accuracy of the obtained Dm values is revisited. For this purpose, Dm values are measured for two representative compounds (Bovine Serum Albumin and Thiourea), and the obtained values are compared with literature data and theoretical recommendations. Based on these observations, a set of 'rules' for accurate and fast Dm measurements is put forward. Finally, an Interactive Tool (IT), combining these rules in a comprehensive way, is introduced and can be used to set up TA experiments.
Collapse
Affiliation(s)
- Donatela Sadriaj
- KU Leuven, Department for Pharmaceutical and Pharmacological Sciences, Pharmaceutical Analysis, Herestraat 49, Leuven, Belgium; Vrije Universiteit Brussel, Department of Chemical Engineering, Pleinlaan 2, 1050 Brussel, Belgium
| | - Gert Desmet
- Vrije Universiteit Brussel, Department of Chemical Engineering, Pleinlaan 2, 1050 Brussel, Belgium
| | - Deirdre Cabooter
- KU Leuven, Department for Pharmaceutical and Pharmacological Sciences, Pharmaceutical Analysis, Herestraat 49, Leuven, Belgium.
| |
Collapse
|
5
|
Moussa A, Lauer T, Stoll D, Desmet G, Broeckhoven K. Modelling of analyte profiles and band broadening generated by interface loops used in multi-dimensional liquid chromatography. J Chromatogr A 2021; 1659:462578. [PMID: 34700181 DOI: 10.1016/j.chroma.2021.462578] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 09/17/2021] [Accepted: 09/21/2021] [Indexed: 11/17/2022]
Abstract
Currently, the shape and variance of the analyte band entering the second dimension column when injected from an open loop interface in two-dimensional liquid chromatography is not fully understood. This is however important as it is connected to several other variables encountered when developing 2D-LC methods, including the first dimension flow rate, the sampling (modulation) time and the loop volume. Both numerical simulation methods and experimental measurements were used to understand and quantify the dispersion occurring in open tubular interface loops. Variables included are the analyte diffusion coefficient (Dmol), loop filling and emptying rates (Ffill & Fempty), loop inner diameter or radius (Rloop) and loop volume (Vloop). For a straight loop capillary, we find that the concentration profile (as measured at the loop outlet) depends only on a single dimensionless parameter tempty*=VloopFempty·DmolRloop2 and the ratio of the filling and emptying flow rates Fempty/Ffill. A model depending only on these two parameters was developed to predict of the peak variance resulting from the filling and emptying of a straight capillary operated in the first-in-last-out (FILO) modulation mode. Comparison of the concentration profiles and the corresponding variances obtained by either numerical simulation or experiments with straight capillaries shows the results generally agree very well. When the straight capillary is replaced by a tightly coiled loop, significantly smaller (20-40%) peak variances are observed compared to straight capillaries. The magnitude of these decreases is not predicted as well by simulations, however the simulation results are still useful in this case, because they represent an upper boundary (i.e., worst-case scenario) on the predicted variance.
Collapse
Affiliation(s)
- Ali Moussa
- Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussel, Belgium
| | - Thomas Lauer
- Gustavus Adolphus College, 800 West College Avenue, Saint Peter, MN, 56082, USA
| | - Dwight Stoll
- Gustavus Adolphus College, 800 West College Avenue, Saint Peter, MN, 56082, USA
| | - Gert Desmet
- Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussel, Belgium
| | - Ken Broeckhoven
- Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussel, Belgium.
| |
Collapse
|
6
|
Nouwade K, Tfaili S, Chaminade P. Investigation of stationary phases performance for eicosanoids profiling in RP-HPLC. Anal Bioanal Chem 2021; 413:6551-6569. [PMID: 34476519 DOI: 10.1007/s00216-021-03618-8] [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: 07/19/2021] [Accepted: 08/11/2021] [Indexed: 11/30/2022]
Abstract
Eicosanoids - oxidative derivatives from arachidonic acid - represent biologically active lipid mediators in inflammatory processes. Different analytical methods treat eicosanoid analysis. Among which, reverse phase liquid chromatography figures as the appropriate method for eicosanoid profiling. RP-HPLC for eicosanoid analysis is often conducted on C18 columns. Some studies focused on profiling one family of eicosanoids; others considered all eicosanoid families. In both cases, co-elution remained a major issue and detection in mass spectrometry partially resolves this problem. In fact, the mass transitions used to monitor eicosanoid species are not specific enough and many isobars can be listed. For this, optimizing the RP-HPLC separation remains important. Based on the parameter Fs - deriving from the hydrophobic-subtraction model - and radar plots, we chose columns with different selectivities. The hydrophobic-subtraction model guided our interpretation of molecular interactions between eicosanoids and stationary phases. We founded our approach for selectivity optimization on peak capacity per minute and time needed values. Herein, we screened seven stationary phases and evaluated their chromatographic performances in RP-HPLC. Stationary phases presented different chemistry, type of silica, length, and particle size. Superficially porous particle columns registered better chromatographic profiles than classical stationary phases; and columns with embedded polar group did not serve our purpose. The stationary phase Accucore C30 - even being the least retentive - revealed the best selectivity and efficiency, and recorded the shorter duration for eicosanoid analysis.
Collapse
Affiliation(s)
- Kodjo Nouwade
- Université Paris-Saclay, Lipides : systèmes analytiques et biologiques, 92296, Châtenay-Malabry, France
| | - Sana Tfaili
- Université Paris-Saclay, Lipides : systèmes analytiques et biologiques, 92296, Châtenay-Malabry, France.
| | - Pierre Chaminade
- Université Paris-Saclay, Lipides : systèmes analytiques et biologiques, 92296, Châtenay-Malabry, France
| |
Collapse
|
7
|
Performance of nanoflow liquid chromatography using core-shell particles: A comparison study. J Chromatogr A 2021; 1648:462218. [PMID: 33992996 DOI: 10.1016/j.chroma.2021.462218] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 04/12/2021] [Accepted: 04/26/2021] [Indexed: 01/23/2023]
Abstract
Due to its unique structure, core-shell material has presented significantly improved chromatographic performance in comparison with conventional totally porous material. This has been well demonstrated in the analytical column format, e.g. 4.6 mm i.d. columns. In the proteomics field, there is always a demand for high resolution microseparation tools. In order to explore core-shell material's potential in proteomics-oriented microseparations, we investigated chromatographic performance of core-shell material in a nanoLC format, as well as its resolving power for protein digests. The results show core-shell nanoLC columns have similar van Deemter curves to the totally porous particle-packed nanoLC columns. For 100 µm i.d. capillary columns, the core-shell material does not have significantly better dynamics. However, both core-shell and totally porous particle-packed nanoLC columns have shown high efficiencies: plate heights of ~11 µm, equivalent to 90000 plates per meter, have been achieved with 5 µm particles. Using a 60 cm long core-shell nanoLC column, 72000 plates were realized in an isocratic separation of neutral compounds. For a 15 cm long nanoLC column, a maximum peak capacity of 220 has been achieved in a 5 hour gradient separation of protein digests, indicating the high resolving power of core-shell nanoLC columns. With a standard HeLa cell lysate as the sample, 2546 proteins were identified by using the core-shell nanoLC column, while 2916 proteins were identified by using the totally porous particle-packed nanoLC column. Comparing the two sets of proteomics data, it was found that 1830 proteins were identified by both columns, while 1086 and 716 proteins were uniquely identified by using totally porous and core-shell particle-packed nanoLC columns, respectively, suggesting their complementarity in nanoLC-MS based proteomics.
Collapse
|
8
|
Blumberg LM. Practical limits to column performance in liquid chromatography - Optimal operations. J Chromatogr A 2020; 1629:461482. [PMID: 32827904 DOI: 10.1016/j.chroma.2020.461482] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 08/11/2020] [Accepted: 08/12/2020] [Indexed: 12/13/2022]
Abstract
Columns of different structures have different potential kinetic performance - the trade-off between separation, time, and pressure. However, the full potential of a structure cannot always be realized in practically existing columns. Each combination of column efficiency, time, and pressure requires certain cross-sectional dimensions of the column flow-through channels. However, there are limits to the narrowest flow-through channels that can be manufactured with current technology. As a result, columns of some structures cannot be optimized for providing the required efficiency in the shortest time. Additionally, the full potential of its structure can be realized only if a column can operate at the highest pressure available from liquid chromatography (LC) equipment, has sufficient loadability, and satisfies other practical requirements. Equations tailored for a systematic approach to evaluation of factors affecting performance of optimized LC columns (effects of column structure, column dimensions, operational conditions, etc.) were developed. Parameters quantifying the performance of a specific column at and below its largest acceptable pressure were identified. New objective performance parameters of columns and their structures were introduced. Among them are the apparent structural quality factor accounting for the effect of insufficiently high pressure acceptable for the column, the dimensionless plate duration - the parameter of a column structure affecting its performance when the pressure is not limited, - and others. Applying the theory developed herein to published data, the performance of several differently structured columns is evaluated, and the factors affecting their comparative performance are discussed. In the final count, not the quality of a column structure, but practical factors such as the narrowest manufacturable flow-through channels can dominate the choice of the kinetically most suitable column for a practical LC analysis.
Collapse
|
9
|
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]
|
10
|
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
| |
Collapse
|
11
|
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]
|
12
|
Gritti F, Gilar M. Impact of frit dispersion on gradient performance in high-throughput liquid chromatography. J Chromatogr A 2019; 1591:110-119. [DOI: 10.1016/j.chroma.2019.01.021] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Revised: 01/05/2019] [Accepted: 01/08/2019] [Indexed: 01/19/2023]
|
13
|
Abstract
The high performance of chemically-modified silica gel packing materials is based on the utilization of pure silica gels. Earlier silica gels used to be made from inorganic silica; however, nowadays, silica gels are made from organic silanes. The surface smoothness and lack of trace metals of new silica gels permits easy surface modifications (chemical reactions) and improves the reproducibility and stability. Sharpening peak symmetry is based on developing better surface modification methods (silylation). Typical examples can be found in the chromatography of amitriptyline for silanol testing and that of quinizarin for trace metal testing. These test compounds were selected and demonstrated sensitive results in the measurement of trace amounts of either silanol or trace metals. Here, we demonstrate the three-dimensional model chemical structures of bonded-phase silica gels with surface electron density for easy understanding of the molecular interaction sites with analytes. Furthermore, a quantitative explanation of hydrophilic and hydrophobic liquid chromatographies was provided. The synthesis methods of superficially porous silica gels and their modified products were introduced.
Collapse
|
14
|
Gritti F. A stochastic view on column efficiency. J Chromatogr A 2018; 1540:55-67. [DOI: 10.1016/j.chroma.2018.02.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 02/01/2018] [Accepted: 02/04/2018] [Indexed: 12/20/2022]
|
15
|
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]
|
16
|
Ahmed A, Skinley K, Herodotou S, Zhang H. Core-shell microspheres with porous nanostructured shells for liquid chromatography. J Sep Sci 2017; 41:99-124. [DOI: 10.1002/jssc.201700850] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2017] [Revised: 09/28/2017] [Accepted: 09/28/2017] [Indexed: 12/19/2022]
Affiliation(s)
| | | | | | - Haifei Zhang
- Department of Chemistry; University of Liverpool; Liverpool UK
| |
Collapse
|
17
|
Stepanova MА, Kinziabulatova LR, Nikitina AA, Korzhikova-Vlakh EG, Tennikova TB. Cholesterol-imprinted macroporous monoliths: Preparation and characterization. Electrophoresis 2017; 38:2965-2974. [PMID: 28881397 DOI: 10.1002/elps.201700335] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 09/02/2017] [Accepted: 09/03/2017] [Indexed: 11/08/2022]
Abstract
The development of sorbents for selective binding of cholesterol, which is a risk factor for cardiovascular disease, has a great importance for analytical science and medicine. In this work, two series of macroporous cholesterol-imprinted monolithic sorbents differing in the composition of functional monomers (methacrylic acid, butyl methacrylate, 2-hydroxyethyl methacrylate and ethylene dimethacrylate), amount of a template (4, 6 and 8 mol%) used for molecular imprinting, as well as mean pore size were synthesized by in situ free-radical process in stainless steel housing of 50 mm × 4.6 mm i.d. All prepared materials were characterized regarding to their hydrodynamic permeability and porous properties, as well as examined by BET and SEM methods. Imprinting factors, apparent dynamic dissociation constants, the maximum binding capacity, the number of theoretical plates and the height equivalent to a theoretical palate of MIP monoliths at different mobile phase flow rates were determined. The separation of a mixture of structural analogues, namely, cholesterol and prednisolone, was demonstrated. Additionally, the possibility of using the developed monoliths for cholesterol solid-phase extraction from simulated biological solution was shown.
Collapse
Affiliation(s)
- Mariia А Stepanova
- Institute of Macromolecular Compounds, Russian Academy of Sciences, St. Petersburg, Russia.,Institute of Chemistry, Saint-Petersburg State University, St. Petersburg, Russia
| | | | - Anna A Nikitina
- Institute of Macromolecular Compounds, Russian Academy of Sciences, St. Petersburg, Russia
| | | | - Tatiana B Tennikova
- Institute of Chemistry, Saint-Petersburg State University, St. Petersburg, Russia
| |
Collapse
|
18
|
|
19
|
Song H, Vanderheyden Y, Adams E, Desmet G, Cabooter D. Extensive database of liquid phase diffusion coefficients of some frequently used test molecules in reversed-phase liquid chromatography and hydrophilic interaction liquid chromatography. J Chromatogr A 2016; 1455:102-112. [DOI: 10.1016/j.chroma.2016.05.054] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2016] [Revised: 05/06/2016] [Accepted: 05/13/2016] [Indexed: 10/21/2022]
|
20
|
Gritti F, Gilar M, Jarrell JA. Quasi-adiabatic vacuum-based column housing for very high-pressure liquid chromatography. J Chromatogr A 2016; 1456:226-34. [DOI: 10.1016/j.chroma.2016.06.029] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Revised: 06/07/2016] [Accepted: 06/08/2016] [Indexed: 11/27/2022]
|
21
|
Gritti F, Gilar M, Jarrell JA. Achieving quasi-adiabatic thermal environment to maximize resolution power in very high-pressure liquid chromatography: Theory, models, and experiments. J Chromatogr A 2016; 1444:86-98. [DOI: 10.1016/j.chroma.2016.03.070] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Revised: 03/22/2016] [Accepted: 03/23/2016] [Indexed: 11/29/2022]
|
22
|
Sampling frequency, response times and embedded signal filtration in fast, high efficiency liquid chromatography: A tutorial. Anal Chim Acta 2016; 907:31-44. [DOI: 10.1016/j.aca.2015.11.043] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Revised: 11/24/2015] [Accepted: 11/25/2015] [Indexed: 11/21/2022]
|
23
|
Tanaka N, McCalley DV. Core–Shell, Ultrasmall Particles, Monoliths, and Other Support Materials in High-Performance Liquid Chromatography. Anal Chem 2015; 88:279-98. [DOI: 10.1021/acs.analchem.5b04093] [Citation(s) in RCA: 119] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
| | - David V. McCalley
- Centre for Research in Biosciences, University of the West of England, Frenchay, Bristol BS16 1QY, U.K
| |
Collapse
|
24
|
Gritti F, McDonald T, Gilar M. Impact of the column hardware volume on resolution in very high pressure liquid chromatography non-invasive investigations. J Chromatogr A 2015; 1420:54-65. [DOI: 10.1016/j.chroma.2015.09.079] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Revised: 09/24/2015] [Accepted: 09/24/2015] [Indexed: 12/28/2022]
|
25
|
Gritti F, McDonald T, Gilar M. Accurate measurement of dispersion data through short and narrow tubes used in very high-pressure liquid chromatography. J Chromatogr A 2015; 1410:118-28. [DOI: 10.1016/j.chroma.2015.07.086] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Revised: 07/20/2015] [Accepted: 07/22/2015] [Indexed: 11/16/2022]
|
26
|
Grinias JP, Kennedy RT. Evaluation of 5 µm Superficially Porous Particles for Capillary and Microfluidic LC Columns. ACTA ACUST UNITED AC 2015; 2:502-514. [PMID: 26714261 PMCID: PMC4669065 DOI: 10.3390/chromatography2030502] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Large-size (4–5 µm) superficially porous particles yield lower plate heights (e.g., the minimal reduced plate height or hmin ≈ 1.5) than fully porous particles of a similar size when packed into large-bore columns. This property allows for better chromatographic performance without the higher pressures required for smaller particles. This study explores the use of such particles in microfluidic LC columns where materials and fitting pressure limits can constrain the size of particle used. The theoretically predicted performance improvements compared to fully porous particles were not demonstrated in capillary columns (with hmin ≈ 2 for both particle types), in agreement with previous studies that examined smaller superficially porous particles. Microfluidic columns were then compared to capillary columns. Capillary columns significantly outperformed microfluidic columns due to imperfections imposed by microfluidic channel asymmetry and world-to-chip connection at the optimal flow rate; however, superficially porous particles packed in microfluidic LC columns had flatter plate height versus flow rate curves indicating potential for better performance at high reduced velocities.
Collapse
Affiliation(s)
- James P. Grinias
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA
| | - Robert T. Kennedy
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109, USA
- Author to whom correspondence should be addressed; ; Tel.: +1-734-615-4376
| |
Collapse
|
27
|
The relative importance of the adsorption and partitioning mechanisms in hydrophilic interaction liquid chromatography. J Chromatogr A 2015; 1376:112-25. [DOI: 10.1016/j.chroma.2014.11.087] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Revised: 11/28/2014] [Accepted: 11/29/2014] [Indexed: 11/18/2022]
|
28
|
Grinias JP, Keil DS, Jorgenson JW. Observation of enhanced heat dissipation in columns packed with superficially porous particles. J Chromatogr A 2014; 1371:261-4. [DOI: 10.1016/j.chroma.2014.10.075] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Revised: 09/29/2014] [Accepted: 10/24/2014] [Indexed: 10/24/2022]
|
29
|
|
30
|
Broeckhoven K, Desmet G. The future of UHPLC: Towards higher pressure and/or smaller particles? Trends Analyt Chem 2014. [DOI: 10.1016/j.trac.2014.06.022] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
31
|
Heaton JC, McCalley DV. Comparison of the kinetic performance and retentivity of sub-2μm core–shell, hybrid and conventional bare silica phases in hydrophilic interaction chromatography. J Chromatogr A 2014; 1371:106-16. [DOI: 10.1016/j.chroma.2014.10.013] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2014] [Revised: 09/01/2014] [Accepted: 10/07/2014] [Indexed: 10/24/2022]
|
32
|
Gritti F, Shiner S, Fairchild JN, Guiochon G. Characterization and kinetic performance of 2.1 × 100 mm production columns packed with new 1.6 μm superficially porous particles. J Sep Sci 2014; 37:3418-25. [DOI: 10.1002/jssc.201400703] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2014] [Revised: 09/03/2014] [Accepted: 09/04/2014] [Indexed: 11/11/2022]
Affiliation(s)
- Fabrice Gritti
- Department of Chemistry University of Tennessee Knoxville TN USA
| | | | | | - Georges Guiochon
- Department of Chemistry University of Tennessee Knoxville TN USA
| |
Collapse
|
33
|
DeStefano JJ, Boyes BE, Schuster SA, Miles WL, Kirkland JJ. Are sub-2 μm particles best for separating small molecules? An alternative. J Chromatogr A 2014; 1368:163-72. [PMID: 25441351 DOI: 10.1016/j.chroma.2014.09.078] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Revised: 09/26/2014] [Accepted: 09/29/2014] [Indexed: 11/24/2022]
Abstract
Superficially porous particles (SPP) in the 2.5-2.7 μm range provide almost the same efficiency and resolution of sub-2 μm totally porous particles (TPP), but at one-half to one-third of the operating pressure. The advantage of SPP has led to the introduction of sub-2 μm SPP as a natural extension of this technology. While short columns of both SPP and TPP sub-2 μm particles allow very fast separations, the efficiency advantages of these very small particles often are not realized nor sufficient to overcome some of the practical limitations and disadvantages of such small particles. Advantages and disadvantages of columns packed with sub-2 μm particles are described for comparison with the characteristics of larger particles. The authors conclude that while sub-2 μm particles have utility in research studies, columns of larger particles are often better suited for most applications. A suggested 2.0 μm superficially porous particle diameter retains many of the advantages of sub-2 μm particles, but minimizes some of the disadvantages. The characteristics of these new 2.0 μm SPP are described in studies comparing some present sub-2 μm SPP commercial columns for efficiency, column bed homogeneity and stability.
Collapse
Affiliation(s)
- Joseph J DeStefano
- Advanced Materials Technology, Inc., 3521 Silverside Rd., Ste. 1-K, Quillen Bldg, Wilmington, DE 19810 USA
| | - Barry E Boyes
- Advanced Materials Technology, Inc., 3521 Silverside Rd., Ste. 1-K, Quillen Bldg, Wilmington, DE 19810 USA
| | - Stephanie A Schuster
- Advanced Materials Technology, Inc., 3521 Silverside Rd., Ste. 1-K, Quillen Bldg, Wilmington, DE 19810 USA.
| | - William L Miles
- Advanced Materials Technology, Inc., 3521 Silverside Rd., Ste. 1-K, Quillen Bldg, Wilmington, DE 19810 USA
| | - Joseph J Kirkland
- Advanced Materials Technology, Inc., 3521 Silverside Rd., Ste. 1-K, Quillen Bldg, Wilmington, DE 19810 USA
| |
Collapse
|
34
|
Gritti F, Bell DS, Guiochon G. Particle size distribution and column efficiency. An ongoing debate revived with 1.9μm Titan-C18 particles. J Chromatogr A 2014; 1355:179-92. [DOI: 10.1016/j.chroma.2014.06.029] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Revised: 06/06/2014] [Accepted: 06/10/2014] [Indexed: 10/25/2022]
|
35
|
Gritti F, Guiochon G. Effect of the pressure on pre-column sample dispersion theory, experiments, and practical consequences. J Chromatogr A 2014; 1352:20-8. [DOI: 10.1016/j.chroma.2014.04.089] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Revised: 04/27/2014] [Accepted: 04/28/2014] [Indexed: 10/25/2022]
|
36
|
Gritti F, Guiochon G. The rationale for the optimum efficiency of columns packed with new 1.9μm fully porous Titan-C18 particles-a detailed investigation of the intra-particle diffusivity. J Chromatogr A 2014; 1355:164-78. [PMID: 24969087 DOI: 10.1016/j.chroma.2014.05.076] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Revised: 05/26/2014] [Accepted: 05/27/2014] [Indexed: 12/01/2022]
Abstract
In a previous report, it was reported that columns packed with fully porous 1.9μm Titan-C18 particles provided a minimum reduced plate height as small as 1.7 for the most retained compound (n-octanophenone) under RPLC conditions. These particles are characterized by a relatively narrow size distribution with a relative standard deviation (RSD) of only 10%. A column packed with classical 5μm Symmetry-C18 particles, used as a reference RPLC column, generated a minimum reduced plate height of 2.1 for the same retained compound. This work demonstrates that this was due to an unusually low intra-particle diffusivity across these particles, which leads to a small longitudinal diffusion coefficient along the column. The demonstration is based on the combination of accurate measurements of the height equivalent to a theoretical plate (HETP), inverse size exclusion chromatography (ISEC), peak parking (PP), and minor disturbance method (MDM) experiments. The experimental results show that the reduced eddy dispersion HETP term (A=0.8 for a reduced velocity of 5), the internal particle porosity (ϵp=0.35), and the enrichment of acetonitrile in the pore volume (75% acetonitrile in the bulk, 85% inside the mesoporous volume) are identical on both the Titan-C18 and Symmetry-C18 columns. The difference between the internal structures of these two brands of RPLC-C18 fully porous particles lies in the values of the internal obstruction factor γp, which is 0.42 for the Symmetry-C18 but only 0.26 for the Titan-C18 particles. This is in part related to the diffusion hindrance due to the small average pore size of the Titan-C18 particles, around 59Å versus 77Å for Symmetry-C18 particles. A simple model of constriction along diffusion paths having the shape of a truncated cone suggests that the width of the pore size distribution (RSD of 30% and 20% for Titan-C18 and Symmetry-C18 particles) is mostly responsible for the difference in their obstruction factors.
Collapse
Affiliation(s)
- Fabrice Gritti
- Department of Chemistry, University of Tennessee, Knoxville, TN 37996-1600, USA
| | - Georges Guiochon
- Department of Chemistry, University of Tennessee, Knoxville, TN 37996-1600, USA.
| |
Collapse
|