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Sang M, Pan N, Wu J, Chen X, Cai S, Fang H, Xiao M, Jiang X, Liu Z. Reversed-Phase Medium-Pressure Liquid Chromatography Purification of Omega-3 Fatty Acid Ethyl Esters Using AQ-C18. Mar Drugs 2024; 22:285. [PMID: 38921596 PMCID: PMC11205217 DOI: 10.3390/md22060285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2024] [Revised: 06/12/2024] [Accepted: 06/14/2024] [Indexed: 06/27/2024] Open
Abstract
Omega-3 fatty acids are in high demand due to their efficacy in treating hypertriglyceridemia and preventing cardiovascular diseases. However, the growth of the industry is hampered by low purity and insufficient productivity. This study aims to develop an efficient RP-MPLC purification method for omega-3 fatty acid ethyl esters with high purity and capacity. The results indicate that the AQ-C18 featuring polar end-capped silanol groups outperformed C18 and others in retention time and impurity separation. By injecting pure fish oil esters with a volume equivalent to a 1.25% bed volume on an AQ-C18 MPLC column using a binary isocratic methanol-water (90:10, v:v) mobile phase at 30 mL/min, optimal omega-3 fatty acid ethyl esters were obtained, with the notable purity of 90.34% and a recovery rate of 74.30%. The total content of EPA and DHA produced increased from 67.91% to 85.27%, meeting the acceptance criteria of no less than 84% set by the 2020 edition of the Pharmacopoeia of the People's Republic of China. In contrast, RP-MPLC significantly enhanced the production efficiency per unit output compared to RP-HPLC. This study demonstrates a pioneering approach to producing omega-3 fatty acid ethyl esters with high purity and of greater quantity using AQ-C18 RP-MPLC, showing this method's significant potential for use in industrial-scale manufacturing.
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Affiliation(s)
- Mingxin Sang
- College of Chemical Engineering, Huaqiao University, Xiamen 361021, China; (M.S.); (M.X.)
- Fisheries Research Institute of Fujian, Xiamen 361013, China; (X.C.); (S.C.); (H.F.)
| | - Nan Pan
- Fisheries Research Institute of Fujian, Xiamen 361013, China; (X.C.); (S.C.); (H.F.)
| | - Jingna Wu
- Xiamen Key Laboratory of Marine Medicinal Natural Products Resources, Fujian Universities and Colleges Engineering Research Center of Marine Biopharmaceutical Resources, Xiamen Medical College, Xiamen 361023, China;
| | - Xiaoting Chen
- Fisheries Research Institute of Fujian, Xiamen 361013, China; (X.C.); (S.C.); (H.F.)
| | - Shuilin Cai
- Fisheries Research Institute of Fujian, Xiamen 361013, China; (X.C.); (S.C.); (H.F.)
| | - Huan Fang
- Fisheries Research Institute of Fujian, Xiamen 361013, China; (X.C.); (S.C.); (H.F.)
- College of Biological Science and Engineering, Fuzhou University, Fuzhou 350108, China
| | - Meitian Xiao
- College of Chemical Engineering, Huaqiao University, Xiamen 361021, China; (M.S.); (M.X.)
| | - Xiaoming Jiang
- Quanzhou Institute of Marine Bioresources Industry, Quanzhou 362000, China;
| | - Zhiyu Liu
- Key Laboratory of Cultivation and High-Value Utilization of Marine Organisms in Fujian Province, National Research and Development Center for Marine Fish Processing (Xiamen), Xiamen 361013, China
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2
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Determination of β-blocking receptor drugs in silica gel TLC systems with the mobile phase containing surfactant. CURRENT ISSUES IN PHARMACY AND MEDICAL SCIENCES 2022. [DOI: 10.2478/cipms-2022-0037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Abstract
Eight drugs blocking beta-adrenergic receptors activity (acebutolol, alprenolol, atenolol, oxprenolol, labetalol, metoprolol, propranolol and sotalol) were investigated through the use of the thin-layer technique with its mobile phase containing surfactant. Assessment of the effect of surfactant presence and 1-propanol concentration in the mobile phase on the retention and separation of investigated solutes was then carried out wherein the effect of the surfactant concentration on the zone shape properties (asymmetry and tailing coefficient) was investigated. The method was applied for the quantitative analysis of the chosen solutes, and the LOD and LOQ values of chosen were determined. These were as follows: acebutolol – 1.11 and 3.36 μg/spot, metoprolol 1.45 μg/spot, 4.4 μg/spot. The chosen system is environmentally friendly due to using silica gel plates and only 5% of propanol in water.
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Kumar R, Kumar A, Kumar A, Tripathi M, Sharma A. Significance of Cartridges and Resins used in a Purification Column during 18F-fluorodeoxyglucose Synthesis. Indian J Nucl Med 2022; 37:318-322. [PMID: 36817206 PMCID: PMC9930447 DOI: 10.4103/ijnm.ijnm_14_22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 03/24/2022] [Accepted: 04/04/2022] [Indexed: 12/04/2022] Open
Abstract
Aims and Objective The aims and objective of this study to share the 15 years of working experience regarding importance of cartridges and resins used in a Purification Column during 18F-FDG synthesis. Materials and Methods 18F- flourodeoxyglucose (18F-FDG) is common radiotracer used in positron emission tomography (PET). 18F-FDG is synthesized in a PET radiochemistry synthesis module and purification column is an integral part of 18F-FDG synthesis. The purification column has four integral parts, namely of ion exchange retardation resin, cation exchange resin, C18 bonded silica, Neutral Alumina. Conclusion The purification column plays a very important role during the synthesis of 18F-FDG. If all parts of the purification column are intact, then maximum transfer of produced 18F-FDG from reaction vessels to the final product vial takes place. The total yield of 18F-FDG is also dependent upon the purification column. If all components of purification column placed tightly and properly charged then there is a high possibility of maximum yield of final product without impurities.
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Affiliation(s)
- Rajeev Kumar
- Department of Nuclear Medicine, IGIMS, Patna, India
| | - Amit Kumar
- Medical Cyclotron Facility, Radiation Medicine Centre, Bhabha Atomic Research Centre, Mumbai, India
| | - Arunav Kumar
- Department of Nuclear Medicine, IGIMS, Patna, India
| | | | - Anshul Sharma
- Departments of Nuclear Medicine, AIIMS, New Delhi, India
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4
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Shang C, Fan F. Preparation of ionogel-bonded mesoporous silica and its application in liquid chromatography. NEW J CHEM 2021. [DOI: 10.1039/d1nj03244e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
A new preparation strategy for stable ionogels on silica obtained by a chemical bonding method and its application in LC.
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Affiliation(s)
- Ce Shang
- E&D Research Institute of Liaohe Oilfield Company, Panjin, 124010, China
| | - Fangbin Fan
- Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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5
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Kadlecová Z, Kalíková K, Ansorge M, Gilar M, Tesařová E. The effect of particle and ligand types on retention and peak shape in liquid chromatography. Microchem J 2020. [DOI: 10.1016/j.microc.2020.105466] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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6
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Pankajkumar-Patel N, Peris-García E, Ruiz-Angel MJ, García-Alvarez-Coque MC. Comparison of surfactant-mediated liquid chromatographic modes with sodium dodecyl sulphate for the analysis of basic drugs. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2020; 12:2443-2452. [PMID: 32930233 DOI: 10.1039/d0ay00526f] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
In reversed-phase liquid chromatography (RPLC), basic drugs are positively charged at the usual working pH range and interact with free anionic silanols present in conventional silica-based stationary phases. This translates into stronger retention and tailed and broadened peaks. This problem can be resolved by the addition of reagents to the mobile phase that are adsorbed on the stationary phase, avoiding the access of solutes to silanols. Among these additives, surfactants under micellar conditions have provided good silanol suppressing potency through the technique known as micellar liquid chromatography (MLC). The most common example of this is anionic sodium dodecyl sulphate (SDS). When SDS is at moderate concentration in the presence of high organic solvent content, micelles are not formed and the chromatographic mode is known as high submicellar liquid chromatography (HSLC). In contrast, the addition of an oil to an aqueous solution of SDS containing micelles gives rise to microemulsions in a chromatographic mode known as microemulsion liquid chromatography (MELC). A comprehensive comparison of the chromatographic behaviour of a set of basic β-adrenoceptor antagonists analysed by MLC, HSLC and MELC is carried out in this work, in terms of retention, peak shape and organic solvent consumption. The study shows that high submicellar eluents reduce retention and enhance efficiency with respect to conventional RPLC and MLC. Meanwhile, MELC allows reduced analysis times with less organic solvent with respect to HSLC. The narrower and more symmetrical peaks in MLC, HSLC and MELC, with respect to conventional RPLC, reveal the presence of silanol masking.
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Affiliation(s)
- N Pankajkumar-Patel
- Departament de Química Analítica, Universitat de València, c/Dr. Moliner 50, Burjassot, Spain.
| | - E Peris-García
- Departament de Química Analítica, Universitat de València, c/Dr. Moliner 50, Burjassot, Spain.
| | - M J Ruiz-Angel
- Departament de Química Analítica, Universitat de València, c/Dr. Moliner 50, Burjassot, Spain.
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7
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Burgos-Gil R, Peris-García E, Ruiz-Angel M, Baeza-Baeza J, García-Alvarez-Coque M. Protocol to compare column performance applied to hydrophilic interaction liquid chromatography. Microchem J 2019. [DOI: 10.1016/j.microc.2019.103973] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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8
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Peris-García E, García-Alvarez-Coque M, Carda-Broch S, Ruiz-Angel M. Effect of buffer nature and concentration on the chromatographic performance of basic compounds in the absence and presence of 1-hexyl-3-methylimidazolium chloride. J Chromatogr A 2019; 1602:397-408. [DOI: 10.1016/j.chroma.2019.06.061] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Revised: 06/26/2019] [Accepted: 06/28/2019] [Indexed: 10/26/2022]
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9
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Ban T, Li XP, Li CL, Wang Q. Surface Characterization of a Series of 1-Alkyl-3-methylimidazolium-Based Ionic Liquids by Inverse Gas Chromatography. Ind Eng Chem Res 2018. [DOI: 10.1021/acs.iecr.8b02110] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Tao Ban
- Center for Physical and Chemical Analysis and Key Laboratory of Coal Cleaning Conversion and Chemical Engineering Process, Xinjiang Uyghur Autonomous Region, College of Chemistry and Chemical Engineering, Xinjiang University, Urumqi 830046, P. R. China
| | - Xiao-Ping Li
- Center for Physical and Chemical Analysis and Key Laboratory of Coal Cleaning Conversion and Chemical Engineering Process, Xinjiang Uyghur Autonomous Region, College of Chemistry and Chemical Engineering, Xinjiang University, Urumqi 830046, P. R. China
| | - Cai-Lian Li
- Center for Physical and Chemical Analysis and Key Laboratory of Coal Cleaning Conversion and Chemical Engineering Process, Xinjiang Uyghur Autonomous Region, College of Chemistry and Chemical Engineering, Xinjiang University, Urumqi 830046, P. R. China
| | - Qiang Wang
- Center for Physical and Chemical Analysis and Key Laboratory of Coal Cleaning Conversion and Chemical Engineering Process, Xinjiang Uyghur Autonomous Region, College of Chemistry and Chemical Engineering, Xinjiang University, Urumqi 830046, P. R. China
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Suitability of 1-hexyl-3-methylimidazolium ionic liquids for the analysis of pharmaceutical formulations containing tricyclic antidepressants. J Chromatogr A 2018; 1559:118-127. [DOI: 10.1016/j.chroma.2017.11.063] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 11/21/2017] [Accepted: 11/26/2017] [Indexed: 11/17/2022]
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11
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Extent of the influence of phosphate buffer and ionic liquids on the reduction of the silanol effect in a C18 stationary phase. J Chromatogr A 2018; 1559:112-117. [DOI: 10.1016/j.chroma.2017.05.061] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Revised: 05/24/2017] [Accepted: 05/29/2017] [Indexed: 11/19/2022]
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12
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Calabuig-Hernández S, García-Alvarez-Coque MC, Ruiz-Angel MJ. Performance of amines as silanol suppressors in reversed-phase liquid chromatography. J Chromatogr A 2016; 1465:98-106. [PMID: 27586325 DOI: 10.1016/j.chroma.2016.08.048] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Revised: 08/18/2016] [Accepted: 08/20/2016] [Indexed: 10/21/2022]
Abstract
In reversed-phase liquid chromatography, cationic basic compounds yield broad and asymmetrical peaks, as a result of their ionic interaction with the anionic free silanol groups present in the silica-based stationary phases (commonly derivatised with C18 groups). A simple way to improve the peak shape is the addition to the hydro-organic mobile phase of a reagent (usually called additive) with cationic character. This associates with the stationary phase to prevent the access of analytes to the free silanol groups. Cationic additives may interact electrostatically with the anionic silanols. The hydrophobic region of the additive may also associate with the alkyl chains bound to the stationary phase, with the positive charge oriented towards the mobile phase. The access to the silanol groups is thus blocked, but in turn, the stationary phase is positively charged and will repel the protonated basic compounds, which unless their polarity is sufficiently low, will elute at very short times. In this work, a comparative study of the performance of a group of amines (butylamine, pentylamine, hexylamine, cyclopentylamine, cycloheptylamine, N,N-dimethyloctylamine and tributylmethylammonium chloride), as modifiers of the chromatographic behaviour of basic compounds, is carried out. The behaviour is compared with that obtained with the ionic liquids 1-butyl-3-methylimidazolium chloride and 1-hexyl-3-methylimidazolium chloride, used as additives. The study revealed that the performance of the cationic additives to block the silanol activity is mainly explained by the additive size and its ability to be adsorbed onto the stationary phase.
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Affiliation(s)
- S Calabuig-Hernández
- Departament de Química Analítica, Universitat de València, c/Dr. Moliner 50, Burjassot, Spain
| | | | - M J Ruiz-Angel
- Departament de Química Analítica, Universitat de València, c/Dr. Moliner 50, Burjassot, Spain.
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13
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Fasciano JM, Danielson ND. Micellar and sub-micellar ultra-high performance liquid chromatography of hydroxybenzoic acid and phthalic acid positional isomers. J Chromatogr A 2016; 1438:150-9. [DOI: 10.1016/j.chroma.2016.02.024] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Revised: 01/18/2016] [Accepted: 02/05/2016] [Indexed: 10/22/2022]
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14
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Yu S, Bian Y, Zhou R, Mou R, Chen M, Cao Z. Robust method for the analysis of phytochelatins in rice by high-performance liquid chromatography coupled with electrospray tandem mass spectrometry based on polymeric column materials. J Sep Sci 2015; 38:4146-52. [PMID: 26541262 DOI: 10.1002/jssc.201500557] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Revised: 09/23/2015] [Accepted: 09/27/2015] [Indexed: 12/26/2022]
Abstract
A sensitive and robust high-performance liquid chromatography coupled with electrospray tandem mass spectrometry method for the identification and quantification of glutathione and phytochelatins from rice was developed. Homogenized samples were extracted with water containing 100 mM dithiothreitol, and solid-phase extraction using polymer anion exchange resin was employed for sample purification. Chromatography was performed on a polymeric column with acetonitrile and water containing 0.1% formic acid as the mobile phase at the flow rate of 300 μL/min. The limit of quantitation was 6-100 nM. This assay showed excellent linearity for both glutathione and phytochelatins over physiological normal ranges, with correlation coefficients (r) > 0.9976. Recoveries for four biothiols were within the range of 76-118%, within relative standard deviations less than 15%. The intraday precision (n = 7) was 2.1-13.3%, and the interday precision over 15 days was 4.3-15.2%. The optimized method was applied to analyze tissue samples from rice grown using nutrient solutions with three different cadmium concentrations (0, 50, and 100 μM). With increasing cadmium concentrations, the content of phytochelatin 2 and phytochelatin 3 in rice roots increased, in contrast to most phytochelatins, and the content of glutathione in rice stems and roots decreased significantly.
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Affiliation(s)
- Shasha Yu
- Rice Product Quality Inspection and Supervision Center of Ministry of Agriculture, China National Rice Research Institute, Hangzhou, China
| | - Yingfang Bian
- Rice Product Quality Inspection and Supervision Center of Ministry of Agriculture, China National Rice Research Institute, Hangzhou, China
| | - Rong Zhou
- Rice Product Quality Inspection and Supervision Center of Ministry of Agriculture, China National Rice Research Institute, Hangzhou, China
| | - Renxiang Mou
- Rice Product Quality Inspection and Supervision Center of Ministry of Agriculture, China National Rice Research Institute, Hangzhou, China
| | - Mingxue Chen
- Rice Product Quality Inspection and Supervision Center of Ministry of Agriculture, China National Rice Research Institute, Hangzhou, China
| | - Zhaoyun Cao
- Rice Product Quality Inspection and Supervision Center of Ministry of Agriculture, China National Rice Research Institute, Hangzhou, China
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15
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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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16
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On the use of ionic liquids as mobile phase additives in high-performance liquid chromatography. A review. Anal Chim Acta 2015; 883:1-21. [PMID: 26088771 DOI: 10.1016/j.aca.2015.03.042] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Revised: 03/24/2015] [Accepted: 03/25/2015] [Indexed: 01/18/2023]
Abstract
The popularity of ionic liquids (ILs) has grown during the last decades in several analytical separation techniques. Consequently, the number of reports devoted to the applications of ILs is still increasing. This review is focused on the use of ILs (mainly imidazolium-based associated to chloride and tetrafluoroborate) as mobile phase additives in high-performance liquid chromatography (HPLC). In this approach, ILs just function as salts, but keep several kinds of intermolecular interactions, which are useful for chromatographic separations. Both cation and anion can be adsorbed on the stationary phase, creating a bilayer. This gives rise to hydrophobic, electrostatic and other specific interactions with the stationary phase and solutes, which modify the retention behaviour and peak shape. This review updates the advances in this field, with emphasis on topics not always deeply considered in the literature, such as the mechanisms of retention, the estimation of the suppressing potency of silanols, modelling and optimisation of the chromatographic performance, and the comparison with other additives traditionally used to avoid the silanol problem.
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Ubeda-Torres MT, Ortiz-Bolsico C, García-Alvarez-Coque MC, Ruiz-Angel MJ. Gaining insight in the behaviour of imidazolium-based ionic liquids as additives in reversed-phase liquid chromatography for the analysis of basic compounds. J Chromatogr A 2014; 1380:96-103. [PMID: 25591403 DOI: 10.1016/j.chroma.2014.12.064] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Revised: 11/27/2014] [Accepted: 12/20/2014] [Indexed: 10/24/2022]
Abstract
In reversed-phase liquid chromatography in the absence of additives, cationic basic compounds give rise to broad and asymmetrical peaks as a result of ionic interactions with residual free silanols on silica-based stationary phases. Ionic liquids (ILs), added to the mobile phase, have been suggested as alternatives to amines to block the activity of silanols. However, the dual character of ILs should be considered: both cation and anion may be adsorbed on the stationary phase, thereby creating a double asymmetrical layer positively or negatively charged, depending on the relative adsorption of both ions. In this work, a study of the performance of six imidazolium-based ILs (the chlorides and tetrafluoroborates of 1-ethyl-, 1-butyl- and 1-hexyl-3-methylimidazolium) as modifiers of the chromatographic behaviour of a group of 10 β-blockers is performed, and compared with triethylamine and dimethyloctylamine. In order to gain more insight in the behaviour of ILs in RPLC, the changes in the nature of the chromatographic system, at increasing concentration of the additives, were followed based on retention and peak shape modelling. The multiple interactions that amines and ILs experience inside the chromatographic system suggest that the suppressing potency should be measured based on the shape of chromatographic peaks and not on the changes in retention. The ILs 1-hexyl-3-methyl-imidazolium chloride and tetrafluoroborate offered the most interesting features for the separation of the basic drugs.
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Affiliation(s)
- M T Ubeda-Torres
- Departament de Química Analítica, Universitat de València, c/Dr. Moliner 50, Burjassot, Spain
| | - C Ortiz-Bolsico
- Departament de Química Analítica, Universitat de València, c/Dr. Moliner 50, Burjassot, Spain
| | | | - M J Ruiz-Angel
- Departament de Química Analítica, Universitat de València, c/Dr. Moliner 50, Burjassot, Spain.
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