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Nai EA, Thurbide KB. A novel switchable water stationary phase for supercritical fluid chromatography. Anal Chim Acta 2023; 1278:341686. [PMID: 37709440 DOI: 10.1016/j.aca.2023.341686] [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: 06/29/2023] [Accepted: 08/02/2023] [Indexed: 09/16/2023]
Abstract
A novel pH switchable water stationary phase is presented for use in supercritical fluid chromatography (SFC). By adding NH4OH to the water coating and system hydration, changes in CO2 pressure and temperature allow a wide range of stationary phase pH conditions (∼3-9) to be achieved, which impact analyte retention properties. For example, 100 atm and 50 °C produces an acidic water stationary phase (pH near 4.0) where octanoic acid readily elutes while the base caffeine does not. Conversely, at 80 atm and 120 °C a basic water stationary phase (pH near 8.0) is obtained and the opposite occurs. Further, under constant pressure and temperature conditions, simply adding or removing NH4OH from the system is also found to readily allow switching between the basic and acidic water stationary phase modes and demonstrates control over ionizable analyte elution. For instance, hexanoic acid elution is near 40 times more delayed on a basic water stationary phase and, as such, it can be eluted at later points in time as desired by removing the NH4OH and switching to an acidic stationary phase. Experiments indicate that stationary phase pH switching occurs uniformly across the 15 m column length within about 18 s and that analyte retention times are very reproducible upon performing a switch (1.4% RSD; n = 3). Results demonstrate the selectivity factor between acidic and neutral analytes can be reversed and increased about 35 times, while in other trials resolution also similarly increased near 40-fold. By rapidly switching the stationary phase pH back and forth between acidic and basic modes, the selectivity between ionizable analytes could also be increased as desired. Various applications with the system show that it can vastly increase the separation between target analytes and matrix components as required by the dynamics of a particular separation.
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Affiliation(s)
- Emmanuel A Nai
- Department of Chemistry, University of Calgary, 2500 University Drive, NW, Calgary, Alberta, T2N 1N4, Canada
| | - Kevin B Thurbide
- Department of Chemistry, University of Calgary, 2500 University Drive, NW, Calgary, Alberta, T2N 1N4, Canada.
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2
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Takekana M, Yoshida T, Yoshida E, Ono S, Horie S, Vavricka CJ, Hiratani M, Tsuge K, Ishii J, Hayakawa Y, Kondo A, Hasunuma T. Online SFE-SFC-MS/MS colony screening: A high-throughput approach for optimizing (-)-limonene production. J Chromatogr B Analyt Technol Biomed Life Sci 2023; 1215:123588. [PMID: 36587464 DOI: 10.1016/j.jchromb.2022.123588] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Revised: 10/22/2022] [Accepted: 12/24/2022] [Indexed: 12/29/2022]
Abstract
Conventional analysis of microbial bioproducers requires the extraction of metabolites from liquid cultures, where the culturing steps are time consuming and greatly limit throughput. To break through this barrier, the current study aims to directly evaluate microbial bioproduction colonies by way of supercritical fluid extraction-supercritical fluid chromatography-triple quadrupole mass spectrometry (SFE-SFC-MS/MS). The online SFE-SFC-MS/MS system offers great potential for high-throughput analysis due to automated metabolite extraction without any need for pretreatment. This is the first report of SFE-SFC-MS/MS as a method for direct colony screening, as demonstrated in the high-throughput screening of (-)-limonene bioproducers. Compared with conventional analysis, the SFE-SFC-MS/MS system enables faster and more convenient screening of highly productive strains.
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Affiliation(s)
- Musashi Takekana
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan
| | - Takanobu Yoshida
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan
| | - Erika Yoshida
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan; Research Institute for Bioscience Products & Fine Chemicals. Ajinomoto Co., Inc. Kanagawa, Japan
| | - Sumika Ono
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan
| | | | - Christopher J Vavricka
- Department of Biotechnology and Life Science, Graduate School of Engineering, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | - Moe Hiratani
- Research Institute for Bioscience Products & Fine Chemicals. Ajinomoto Co., Inc. Kanagawa, Japan
| | - Kenji Tsuge
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan
| | - Jun Ishii
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan; Engineering Biology Research Center, Kobe University, Kobe, Japan
| | | | - Akihiko Kondo
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan; Engineering Biology Research Center, Kobe University, Kobe, Japan
| | - Tomohisa Hasunuma
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan; Engineering Biology Research Center, Kobe University, Kobe, Japan.
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Nai EA, Thurbide KB. Supercritical Fluid Chromatography of Organic Bases Using a Modified Water Stationary Phase. Chromatographia 2022. [DOI: 10.1007/s10337-022-04208-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Shah PA, Shrivastav PS, Sharma VS. Supercritical fluid chromatography for the analysis of antihypertensive Drugs: A short review. Microchem J 2022. [DOI: 10.1016/j.microc.2022.107341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Measurements of drugs and metabolites in biological matrices using SFC and SFE-SFC-MS. SEP SCI TECHNOL 2022. [DOI: 10.1016/b978-0-323-88487-7.00004-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
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6
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Tanaka S, Uchiyama N, Goda T, Iida T, Horie S, Masada S, Arai R, Yamamoto E, Hakamatsuka T, Okuda H, Goda Y. A simple and rapid method to simultaneously analyze ciclesonide and its impurities in a ciclesonide metered-dose inhaler using on-line supercritical fluid extraction/supercritical fluid chromatography/quadrupole time-of-flight mass spectrometry. J Pharm Biomed Anal 2021; 204:114253. [PMID: 34271287 DOI: 10.1016/j.jpba.2021.114253] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 07/05/2021] [Accepted: 07/05/2021] [Indexed: 01/11/2023]
Abstract
A simple and rapid on-line SFE/SFC/quadrupole TOF-MS method to simultaneously analyze active pharmaceutical ingredients and impurities from metered-dose inhalers (MDIs) was developed using ciclesonide MDI (CIC-MDI) as an example. CIC-MDI, as drug Alvesco®, has been approved for the treatment of bronchial asthma, and its major impurities are listed in the European Pharmacopoeia and in the supplementary package inserts of Alvesco® (called as "Pharmaceutical interview form" in Japan). In the developed method, CIC-MDI was manually sprayed only once on a glass disc prior to the SFE/SFC/quadrupole TOF-MS. In the SFE, CIC and its impurities and other impurities having various polarities and hydrophobicity, were extracted in 3.5 min and subsequently separated on a CHIRALPAK IE-3 column to be detected by quadrupole TOF-MS in 6.5 min. This method would be applicable to the analysis of other inhalable pharmaceutical products whose sample preparation requires complicated procedures, as well as to the analysis of general pharmaceutical products for profiling impurities.
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Affiliation(s)
- Seiji Tanaka
- Division of Pharmacognosy, Phytochemistry and Narcotics, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki, Kanagawa, 210-9501, Japan
| | - Nahoko Uchiyama
- Division of Pharmacognosy, Phytochemistry and Narcotics, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki, Kanagawa, 210-9501, Japan.
| | - Takahiro Goda
- Shimadzu Corporation, 1 Nishinokyo Kuwabara-cho, Nakagyo-ku, Kyoto, 604-8511, Japan
| | - Tetsuo Iida
- Shimadzu Corporation, 1 Nishinokyo Kuwabara-cho, Nakagyo-ku, Kyoto, 604-8511, Japan
| | - Shinnosuke Horie
- Shimadzu Corporation, 1 Nishinokyo Kuwabara-cho, Nakagyo-ku, Kyoto, 604-8511, Japan
| | - Sayaka Masada
- Division of Pharmacognosy, Phytochemistry and Narcotics, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki, Kanagawa, 210-9501, Japan
| | - Ryoko Arai
- Division of Pharmacognosy, Phytochemistry and Narcotics, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki, Kanagawa, 210-9501, Japan
| | - Eiichi Yamamoto
- Division of Drugs, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki, Kanagawa, 210-9501, Japan
| | - Takashi Hakamatsuka
- Division of Pharmacognosy, Phytochemistry and Narcotics, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki, Kanagawa, 210-9501, Japan
| | - Haruhiro Okuda
- National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki, Kanagawa, 210-9501, Japan
| | - Yukihiro Goda
- National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki, Kanagawa, 210-9501, Japan
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Chemical derivatization in combination with supercritical fluid chromatography to improve resolution of stereoisomers. Bioanalysis 2021; 13:985-999. [PMID: 34081541 DOI: 10.4155/bio-2021-0053] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Aim: Quantification of stereoisomers in biological matrices is of pivotal importance for drug development. Supercritical fluid chromatography paired with chiral stationary phases is the gold standard for resolution of enantiomers. However, this technique often proves inadequate for resolution of polar stereoisomers. Materials & methods: A combination of achiral chemical derivatization with supercritical fluid chromatography using chiral stationary columns to improve enantiomeric resolution is described. Results: Separation of four possible stereoisomers of linerixibat was achieved after derivatization with 3N HCl in n-butanol within 12 min (case1). Derivatization with acetic, propionic, butyric, isobutyric, valeric and isovaleric anhydrides significantly improved the separation of stereoisomers (case 2 and 3) within 10 min. The best stereoisomeric resolution was achieved using valeric and isovaleric anhydrides.
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Krčmová LK, Melichar B, Švec F. Chromatographic methods development for clinical practice: requirements and limitations. Clin Chem Lab Med 2020; 58:1785-1793. [DOI: 10.1515/cclm-2020-0517] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Accepted: 05/25/2020] [Indexed: 12/30/2022]
Abstract
Abstract
Development of a chromatographic method in bioanalysis is a challenging and complex procedure with many pitfalls and often unexpected reversals that can require several months to accomplish. Even an experienced analytical team must contend many limitations mainly in connection with the strict requirements imposed on current clinical research. These restrictions typically persist throughout the whole development process, from clinical trial assignment, across optimization of extraction of biological materials and chromatographic separation, to validation and data interpretation. This paper describes questions and their possible answers raised during the pre-analytical phase such as use of modern sample preparation techniques in clinical methods, application of internal standards, as well as selection of stationary phases and detection techniques in the analytical phase. Validation problems and interpretation of results are demonstrated with three typical examples of characteristics to be considered, i.e. recovery, matrix effect, and limit of detection vs. lower limit of quantification.
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Affiliation(s)
- Lenka Kujovská Krčmová
- The Department of Analytical Chemistry, Faculty of Pharmacy , Charles University , Hradec Králové , Czech Republic
- The Department of Clinical Biochemistry and Diagnostics , University Hospital , Sokolská 581, 500 05 Hradec Králové , Czech Republic
| | - Bohuslav Melichar
- The Department of Oncology, Faculty of Medicine and Dentistry , Palacky University , Olomouc , Olomouc , Czech Republic
| | - František Švec
- The Department of Analytical Chemistry, Faculty of Pharmacy , Charles University , Hradec Králové , Czech Republic
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Scott AF, Thurbide KB. Retention Characteristics of a pH Tunable Water Stationary Phase in Supercritical Fluid Chromatography. J Chromatogr Sci 2016; 55:82-89. [DOI: 10.1093/chromsci/bmw153] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Revised: 07/06/2016] [Indexed: 11/14/2022]
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10
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Hekayati J, Roosta A, Javanmardi J. Volumetric properties of supercritical carbon dioxide from volume-translated and modified Peng-Robinson equations of state. KOREAN J CHEM ENG 2016. [DOI: 10.1007/s11814-016-0176-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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11
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Advances in LC: bioanalytical method transfer. Bioanalysis 2016; 8:1837-44. [PMID: 27491842 DOI: 10.4155/bio-2016-4999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
There are three main reasons for transferring from an existing bioanalytical assay to an alternative chromatographic method: speed, cost and sensitivity. These represent a challenge to the analyst in that there is an interplay between these three considerations and one factor is often improved at the expense of another. These three factors act as drivers to encourage technology development and support its uptake. The more recently introduced chromatographic technologies may show significant improvements against one of more of these factors relative to conventional 4.6-mm id reversed-phase HPLC. In this article, some of these new chromatographic approaches will be considered in terms of what they can offer the bioanalysts.
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Overcoming bioanalytical challenges associated with the separation and quantitation of GSK1278863, a HIF-prolyl hydroxylase inhibitor, and its 14 stereoisomeric metabolites. J Chromatogr B Analyt Technol Biomed Life Sci 2016; 1009-1010:7-16. [DOI: 10.1016/j.jchromb.2015.11.057] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Revised: 11/18/2015] [Accepted: 11/22/2015] [Indexed: 11/23/2022]
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Camphanic acid chloride: a powerful derivatization reagent for stereoisomeric separation and its DMPK applications. Bioanalysis 2015; 7:3005-17. [DOI: 10.4155/bio.15.219] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Background: Camphanic acid chloride has proven to be an efficient chiral derivatization reagent for determination of stereoisomers. Results: The utility of chemical derivatization of various stereoisomers containing hydroxy functional groups with camphanic acid chloride in the presence or absence of a base is highlighted. This procedure is shown to be relatively simple, fast and a cost-effective method of separating racemic drugs and stereoisomeric metabolites in biological matrices. Camphanic derivatives contain two additional chirogenic centers, which are found to enhance stereoisomeric separation on both traditional and chiral stationary phases. Conclusion: Four methodologies described herein for separation of multiple stereoisomers in biological samples confirm camphanic acid chloride to be a powerful chiral reagent for stereoisomeric resolution for drug metabolism and PK applications.
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Toward greener analytical techniques for the absolute quantification of peptides in pharmaceutical and biological samples. J Pharm Biomed Anal 2015; 113:181-8. [DOI: 10.1016/j.jpba.2015.03.023] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Revised: 03/19/2015] [Accepted: 03/23/2015] [Indexed: 11/22/2022]
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Supercritical fluid chromatography in pharmaceutical analysis. J Pharm Biomed Anal 2015; 113:56-71. [DOI: 10.1016/j.jpba.2015.03.007] [Citation(s) in RCA: 164] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Revised: 03/03/2015] [Accepted: 03/05/2015] [Indexed: 12/21/2022]
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17
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Biological sample preparation: attempts on productivity increasing in bioanalysis. Bioanalysis 2014; 6:1691-710. [DOI: 10.4155/bio.14.118] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Sample preparation is an important step of any biomedical analysis. Development and validation of fast, reproducible and reliable sample preparation methods would be very helpful in increasing productivity. Except for a few direct injection methods, almost all biological samples should at least be diluted before any analysis. Sometimes dilution is not possible because of the low concentration of the target analyte in the sample, and alternative pretreatments, such as filtration, precipitation and sample clean up using different extraction methods, are needed. This review focuses on the recent achievements in the pretreatment of biological samples and investigates them in six categories (i.e., dilution, filtration/dialysis, precipitation, extraction [solid-phase extraction, liquid–liquid extraction], novel techniques [turbulent flow chromatography, immunoaffinity method, electromembrane extraction] and combined methods). Each category will be discussed according to its productivity rate and suitability for routine analysis, and the discussed methods will be compared according to the mentioned indices.
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Scott AF, Thurbide KB. Comparative Response Characterization of a Universal Acoustic Flame Detector for Chromatography. Chromatographia 2014. [DOI: 10.1007/s10337-014-2692-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Multi-target screening of biological samples using LC–MS/MS: focus on chromatographic innovations. Bioanalysis 2014; 6:1255-73. [DOI: 10.4155/bio.14.80] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Multi-target screening of biological fluids is a key tool in clinical and forensic toxicology. A complete toxicological analysis encompasses the sample preparation, the chromatographic separation and the detection. The present review briefly covers the new trends in sample preparation and detection and mainly focuses on the chromatographic stage, since a lot of technical improvements have been proposed over the last years. Among them, columns packed with sub-2 μm fully porous particles and sub-3 μm core-shell particles allow for significant improvements of resolution and higher throughput. Even if reversed-phase LC remains the most widely used chromatographic mode for toxicological screening, hydrophilic interaction chromatography and supercritical fluid chromatography appear as promising alternatives for attaining orthogonal selectivity, retention of polar compounds, and enhanced MS sensitivity.
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Application of supercritical fluid carbon dioxide to the extraction and analysis of lipids. Bioanalysis 2012; 4:2413-22. [DOI: 10.4155/bio.12.198] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Supercritical carbon dioxide (SCCO2) is an ecofriendly supercritical fluid that is chemically inert, nontoxic, noninflammable and nonpolluting. As a green material, SCCO2 has desirable properties such as high density, low viscosity and high diffusivity that make it suitable for use as a solvent in supercritical fluid extraction, an effective and environment-friendly analytical method, and as a mobile phase for supercritical fluid chromatography, which facilitates high-throughput, high-resolution analysis. Furthermore, the low polarity of SCCO2 is suitable for the extraction and analysis of hydrophobic compounds. The growing concern surrounding environmental pollution has triggered the development of green analysis methods based on the use of SCCO2 in various laboratories and industries. SCCO2 is becoming an effective alternative to conventional organic solvents. In this review, the usefulness of SCCO2 in supercritical fluid extraction and supercritical fluid chromatography for the extraction and analysis of lipids is described.
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Uchikata T, Matsubara A, Fukusaki E, Bamba T. High-throughput phospholipid profiling system based on supercritical fluid extraction–supercritical fluid chromatography/mass spectrometry for dried plasma spot analysis. J Chromatogr A 2012; 1250:69-75. [DOI: 10.1016/j.chroma.2012.06.031] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2012] [Revised: 06/07/2012] [Accepted: 06/08/2012] [Indexed: 10/28/2022]
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Papetti A. Isolation and characterization of antimicrobial food components. Curr Opin Biotechnol 2012; 23:168-73. [DOI: 10.1016/j.copbio.2011.09.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2011] [Revised: 09/07/2011] [Accepted: 09/14/2011] [Indexed: 11/24/2022]
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Supercritical fluid chromatography for bioanalysis: practical and theoretical considerations. Bioanalysis 2011; 3:125-31. [PMID: 21250840 DOI: 10.4155/bio.10.188] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
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Abstract
The acetonitrile shortage during 2008 to 2009 challenged bioanalytical scientists due to the ubiquitous role that acetonitrile plays in sample preparation and analysis. Replacement, reduction and reuse of acetonitrile were the core tenants behind each approach used to tackle the shortage. Sample preparation of biological matrices can be accomplished by protein precipitation using a variety of solvents; methanol is usually the best substitute for acetonitrile. The potential liabilities in using methanol can be handled with appropriate modifications. Often methanol is superior to acetonitrile for both protein precipitation and chromatography if phospholipid interference is a problem. Solvent consumption can be minimized by reducing column dimensions and particle size. Separations can be achieved at greatly reduced run times using sub-2-μm and fused-core particle columns. Emerging technologies, such as desorption ESI, direct analysis in real time and laser diode thermal desorption, eliminate the need for chromatography and achieve significant solvent and time savings. Acetonitrile recyclers can purify HPLC waste for reuse.
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