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Fairchild JN, Horváth K, Guiochon G. Approaches to comprehensive multidimensional liquid chromatography systems. J Chromatogr A 2008; 1216:1363-71. [PMID: 19150720 DOI: 10.1016/j.chroma.2008.12.073] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2008] [Revised: 12/12/2008] [Accepted: 12/22/2008] [Indexed: 12/11/2022]
Abstract
This work compares the performance of the three different schemes implementing two-dimensional liquid chromatography (2D-LC) in terms of the peak capacity that they can generate and of the time that they need to complete a two-dimensional analysis. We discuss in detail how time is spent in these two-dimensional liquid chromatography x liquid chromatography (LC x LC) schemes and how to compare them. Keeping constant the characteristics of the first-dimension separation, we systematically varied those of the second-dimension separation and of its coupling to the first-dimension. In the process, five systems were created, based on the principles of the three known implementations of comprehensive 2D-LC. This work demonstrates an original method for the selection of the best comprehensive 2D-LC approach, depending on the desired peak capacity and on time constraints. The decision to use a 2D-LC method arises from the need to achieve a given resolution (i.e., a target peak capacity) within as short a time as possible or to reach the highest possible resolution in a given analysis time. Using the most appropriate schemes, we suggest how it is realistically possible to generate peak capacities ranging from 266 in just over 20 min or about 2800 in 2.3 h. When the time available for a two-dimensional separation is very short and the desired peak capacity cannot be achieved in 1D-LC, an on-line 2D-LC approach is unquestionably best. However, if a longer analysis time is acceptable, a 10-fold increase in the peak capacity can be obtained at the cost of a mere 7-fold increase in total analysis time.
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Affiliation(s)
- Jacob N Fairchild
- Department of Chemistry, University of Tennessee, Knoxville, TN 37996-1600, USA
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52
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Kivilompolo M, Hyötyläinen T. Comparison of separation power of ultra performance liquid chromatography and comprehensive two-dimensional liquid chromatography in the separation of phenolic compounds in beverages. J Sep Sci 2008; 31:3466-72. [DOI: 10.1002/jssc.200800287] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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53
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Optimization of separation in two-dimensional high-performance liquid chromatography by adjusting phase system selectivity and using programmed elution techniques. J Chromatogr A 2008; 1189:207-20. [DOI: 10.1016/j.chroma.2007.11.053] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2007] [Revised: 11/09/2007] [Accepted: 11/19/2007] [Indexed: 11/27/2022]
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54
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Kivilompolo M, Obůrka V, Hyötyläinen T. Comprehensive two-dimensional liquid chromatography in the analysis of antioxidant phenolic compounds in wines and juices. Anal Bioanal Chem 2008; 391:373-80. [DOI: 10.1007/s00216-008-1997-9] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2007] [Revised: 01/28/2008] [Accepted: 02/19/2008] [Indexed: 11/29/2022]
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55
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Stalikas CD. Extraction, separation, and detection methods for phenolic acids and flavonoids. J Sep Sci 2008; 30:3268-95. [PMID: 18069740 DOI: 10.1002/jssc.200700261] [Citation(s) in RCA: 446] [Impact Index Per Article: 27.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The impetus for developing analytical methods for phenolic compounds in natural products has proved to be multifaceted. Hundreds of publications on the analysis of this category of compounds have appeared over the past two decades. Traditional and more advanced techniques have come to prominence for sample preparation, separation, detection, and identification. This review provides an updated and extensive overview of methods and their applications in natural product matrices and samples of biological origin. In addition, it critically appraises recent developments and trends, and provides selected representative bibliographic examples.
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56
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Dugo P, Cacciola F, Kumm T, Dugo G, Mondello L. Comprehensive multidimensional liquid chromatography: Theory and applications. J Chromatogr A 2008; 1184:353-68. [PMID: 17655853 DOI: 10.1016/j.chroma.2007.06.074] [Citation(s) in RCA: 231] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2007] [Revised: 06/27/2007] [Accepted: 06/28/2007] [Indexed: 11/23/2022]
Abstract
Comprehensive two-dimensional (2D) liquid chromatographic (LC x LC) techniques can be considered innovative methods only recently developed and adopted in many configurations. The revolutionary aspect of comprehensive two-dimensional techniques, with respect to classical multidimensional (MD) chromatography, is that the entire sample is subjected to the 2D advantage. The major benefit is that the separation capacities of each dimension are multiplied, offering a high peak capacity to resolve samples of great complexity. The first part of the present review briefly describes the theoretical and practical aspects related to the development of a multidimensional comprehensive liquid chromatographic method. Applicational experiences in comprehensive liquid chromatography are then described, divided into four groups, according to the HPLC modes used in the two dimensions and to the nature of the samples analyzed.
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Affiliation(s)
- Paola Dugo
- Dipartimento di Scienza degli alimenti e dell'ambiente, Facoltà di Scienze, Università di Messina, Salita Sperone 31, 98166 Messina, Italy.
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Cong J, Lin B. Study of Separation Conditions of Active Components in Licorice with Two‐Dimensional Liquid Chromatography. J LIQ CHROMATOGR R T 2008. [DOI: 10.1080/10826070801893516] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Jingxiang Cong
- a School of Chemical Engineering, Dalian University of Technology , Dalian, Liaoning, P. R. China
- b Center of Separation Technology,University of Science and Technology , Anshan, Liaoning, P. R. China
| | - Bingchang Lin
- b Center of Separation Technology,University of Science and Technology , Anshan, Liaoning, P. R. China
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58
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Beldean‐Galea MS, Jandera P, Hodisan S. Retention and Separation Selectivity of Natural Phenolic Antioxidants on Zirconia Based Stationary Phases. J LIQ CHROMATOGR R T 2008. [DOI: 10.1080/10826070801890454] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
| | - Pavel Jandera
- b Faculty of Chemical Technology , University of Pardubice , Czech Republic
| | - Sorin Hodisan
- c Faculty of Science , University of Oradea , Oradea, Romania
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59
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François I, de Villiers A, Tienpont B, David F, Sandra P. Comprehensive two-dimensional liquid chromatography applying two parallel columns in the second dimension. J Chromatogr A 2007; 1178:33-42. [PMID: 18054028 DOI: 10.1016/j.chroma.2007.11.032] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2007] [Revised: 11/05/2007] [Accepted: 11/12/2007] [Indexed: 11/25/2022]
Abstract
The design of a new interface for comprehensive two-dimensional liquid chromatography (LC x LC) is described. To the conventionally used LC x LC system with the loop-type interface consisting of a two-position/ten-port switching valve equipped with two loops, an extra two-position/ten-port switching valve, a detector, a pump and a second column placed in parallel with the column in the second dimension, are added. The features of the interface are that the separation space in the second dimension is significantly enlarged and that the number of fractions transferred from the first to the second dimension can be increased, reducing the risk to lose resolution of the primary dimension. The potential of the system in NPLC x 2RPLC is illustrated with the analysis of a standard mixture and a lemon oil extract. For the lemon oil analysis, the effective peak capacity was increased from 437 using a conventional interface to 1095 with the new interface. RPLC x 2RPLC in combination with reduced modulation times was applied to the analysis of steroids and to the detection of impurities at the 0.05% relative concentration level in a sulfonamide drug sample.
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Affiliation(s)
- Isabelle François
- Ghent University, Department of Organic Chemistry, Krijgslaan 281 (S4-bis), B-9000 Ghent, Belgium
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60
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Abstract
The properties of stationary phases and their characterization methods are reviewed. New and significant developments have occurred in the last few years, and new methods for stationary phase characterization have become available. The characterization methods are discussed, and the differences between the different methods are pointed out. In addition, method development approaches are reviewed, with special emphasis on recent developments that employ multiple parameters in parallel. Also, the renewed interest of temperature as a tool in method development is surveyed.
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Affiliation(s)
- Uwe D Neue
- Waters Corporation, Milford, MA 01757, USA.
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61
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Cacciola F, Jandera P, Hajdú Z, Cesla P, Mondello L. Comprehensive two-dimensional liquid chromatography with parallel gradients for separation of phenolic and flavone antioxidants. J Chromatogr A 2007; 1149:73-87. [PMID: 17331519 DOI: 10.1016/j.chroma.2007.01.119] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2006] [Revised: 01/23/2007] [Accepted: 01/25/2007] [Indexed: 10/23/2022]
Abstract
Various combinations of PEG-silica, phenyl-silica and C18 columns in a single-column or serial (tandem) arrangement in the first dimension and a monolithic Chromolith column in the second dimension were tested for comprehensive two-dimensional (2D) LCxLC separation of phenolic and flavone natural antioxidants. The combinations of different stationary phase chemistries provided low selectivity correlations between the first-dimension and the second-dimension separation systems. Improvement in system orthogonality, bandwidths suppression, more regular band distribution over the whole 2D retention plane and increased peak capacity in different 2D setups was achieved by using gradients with matching profiles running in parallel in the two dimensions over the whole 2D separation time range. Instead of two sampling loops, two alternating trapping XTerra columns were used for sample fraction transfer from the first-dimension column to the second dimension. Stronger retention on the XTerra columns in comparison to PEG-silica or phenyl-silica columns in the first dimension allowed using focusing of sample fractions in narrow zones on the top of a trapping column and back-flushing into the second dimension in a very low volume of the mobile phase. This fraction transfer modulation provided significant bandwidth suppression in the second dimension. 2D systems with optimized stationary phase selectivity, parallel gradients and fraction transfer modulation using two trapping columns were applied for the analysis of natural antioxidants in beer and wine samples.
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Affiliation(s)
- F Cacciola
- Department of Analytical Chemistry, University of Pardubice, Pardubice, Czech Republic
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62
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Kivilompolo M, Hyötyläinen T. Comprehensive two-dimensional liquid chromatography in analysis of Lamiaceae herbs: Characterisation and quantification of antioxidant phenolic acids. J Chromatogr A 2007; 1145:155-64. [PMID: 17307195 DOI: 10.1016/j.chroma.2007.01.090] [Citation(s) in RCA: 150] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2006] [Revised: 01/16/2007] [Accepted: 01/19/2007] [Indexed: 11/25/2022]
Abstract
A fast and effective dynamic sonication assisted ethanol extraction method was developed for extracting phenolic acids from basil, oregano, rosemary, sage, spearmint and thyme of the Lamiaceae family. The results were compared with results obtained by conventional solvent extraction techniques. A comprehensive two-dimensional liquid chromatography (LC x LC) system interfaced to electrospray ionisation time-of-flight (TOF) mass spectrometry was then optimised for analysis and quantification of the herb extracts. The optimised LC x LC system employed a combination of C18 and cyano columns. The relative standard deviations for the retention times were better than 0.05% (rosmarinic acid 0.1%) and those for the peak areas 2-14% (2 mg/l, n=3). Limits of detection were 18-90 ng/ml. The LC x LC-MS method was applied to the quantitative analysis of phenolic acids, and the results were compared with those obtained with conventional LC-MS.
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Affiliation(s)
- Maarit Kivilompolo
- Laboratory of Analytical Chemistry, Department of Chemistry, University of Helsinki, P.O. Box 55, FIN-00014, Helsinki, Finland
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63
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Cacciola F, Jandera P, Mondello L. Temperature effects on separation on zirconia columns: Applications to one- and two-dimensional LC separations of phenolic antioxidants. J Sep Sci 2007; 30:462-74. [PMID: 17444215 DOI: 10.1002/jssc.200600387] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The effects of temperature and mobile phase on LC chromatographic separation of phenolic antioxidants on zirconia-based columns were investigated. Unlike silica-based materials, zirconia columns show excellent thermal stability over a wide range of temperatures and enable high-temperature separations. Enthalpic and entropic contributions to the retention of phenolic compounds on ZR-Carbon and ZR-Carbon C18 columns were determined from retention versus temperature plots in order to elucidate the retention mechanism of sample compounds over the temperature range up to 14 degrees C. High-temperature liquid chromatography on ZR-Carbon columns was used for comprehensive LC x LC two-dimensional separation systems based on the different selectivity of a Zorbax SB micro-column used in the first dimension and a ZR-Carbon column used in the second dimension. Two-dimensional LC x LC systems employing a setup with two alternately operated parallel ZR-Carbon columns in the second dimension were used for the analysis of phenolic antioxidants in beer and wine samples.
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Affiliation(s)
- Francesco Cacciola
- Department of Analytical Chemistry, University of Pardubice, Pardubice, Czech Republic
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64
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Cacciola F, Jandera P, Blahová E, Mondello L. Development of different comprehensive two dimensional systems for the separation of phenolic antioxidants. J Sep Sci 2006; 29:2500-13. [PMID: 17154131 DOI: 10.1002/jssc.200600213] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Three different comprehensive 2-D HPLC systems for the separation of phenolic antioxidants have been developed on the basis of different selectivities of a PEG-silica column in the first dimension and a packed or monolithic C18 or a ZR-CARBON column, respectively, in the second dimension. Two-dimensional comprehensive liquid chromatography using a serially connected short PEG-silica column and a conventional C18-silica or a ZR-CARBON column in the second dimension was tested to improve the resolution of the earlier eluting compounds in the first dimension. Various types of interface were used to connect the columns in the first and in the second dimension: i) two injection sampling loops of 100 microL in conventional arrangement; ii) a 10-port 2-position valve equipped with two trapping X-Terra columns instead of loops; and iii) two analytical D2 columns in parallel. The mobile phase in the first dimension has a lower elution strength than in the second dimension, allowing band compression of the solutes transferred from the first to the second dimension. This effect was enhanced using trapping columns instead of sampling loops as the interface between the two dimensions, thus allowing a decrease in the time of analysis. These systems were used for the analysis of beer samples. The relative location of the components in the 2-D retention plane varied in relation to their chemical structure in each instrumental set-up and allowed positive peak identification.
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Affiliation(s)
- Francesco Cacciola
- Department of Analytical Chemistry, University of Pardubice, Pardubice, Czech Republic
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65
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Abstract
Selectivity of phase system is of primary concern when designing a 2-D separation, as it affects the 2-D system orthogonality and consequently the peak capacity controlling the number of peaks that can be separated in the available 2-D retention space limited by the time of analysis. Possibilities for characterization of LC phase system selectivity with respect to different polar and nonpolar structural units are compared, with special attention to multidimensional samples with various types of repeat groups, such as homopolymers, (co)polymers, fatty acid esters with various acyl lengths and number and position of double bonds, etc. Possibilities of the 2-D LC separations of these and other sample types, including pharmaceuticals, natural phenolic compounds, biopolymers, etc., using various combinations of separation modes are reviewed. Rules for design of comprehensive 2-D LC x LC systems are discussed, with respect to mobile phase compatibility in the two systems and modulation techniques suppressing band broadening connected with the sample fraction transfer from the first to the second dimension. Pitfalls connected with online connection of normal-phase and RP LC systems and their possible practical solutions are addressed and illustrated by practical examples.
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Affiliation(s)
- Pavel Jandera
- Department of Analytical Chemistry, Faculty of Chemical Technology, University of Pardubice, Pardubice, Czech Republic.
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