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Zhu H, He L, Wu W, Duan H, Chen J, Xiao Q, Lin P, Qin Z, Dai Y, Wu W, Hu L, Yao Z. A compounds annotation strategy using targeted molecular networking for offline two-dimensional liquid chromatography-mass spectrometry analysis: Yupingfeng as a case study. J Chromatogr A 2023; 1702:464045. [PMID: 37236139 DOI: 10.1016/j.chroma.2023.464045] [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: 01/13/2023] [Revised: 03/26/2023] [Accepted: 05/02/2023] [Indexed: 05/28/2023]
Abstract
Component overlapping and long-time consumption hinder the data processing of offline two-dimensional liquid chromatography mass spectrometry (offline 2D-LC MS) system. Although molecular networking has been commonly employed in data processing of liquid chromatography mass spectrometry (LC-MS), its application in offline 2D-LC MS is challenged by voluminous and redundant data. In light of this, for the first time, a data deduplication and visualization strategy combining hand-in-hand alignment with targeted molecular networking (TMN) for compounds annotation of offline 2D-LC MS data was developed and applied to the chemical profile of Yupingfeng (YPF), a classical traditional Chinese medicine (TCM) prescription, as a case study. Firstly, an offline 2D-LC MS system was constructed for the separation and data acquisition of YPF extract. Then the data of 12 fractions derived from YPF were deconvoluted and aligned as a whole data file by hand-in-hand alignment, resulting in a 49.2% reduction in component overlapping (from 17951 to 9112 ions) and an improvement in the MS2 spectrum quality of precursor ions. Subsequently, the MS2-similarity adjacency matrix of focused parent ions was computed by a self-building Python script, which realized the construction of an innovative TMN. Interestingly, the TMN was found to be able to efficiently distinguish and visualize the co-elution, in-source fragmentations and multi-type adduct ions in a clustering network. Consequently, a total of 497 compounds were successfully identified depending on only seven TMN analysis guided by product ions filtering (PIF) and neutral loss filtering (NLF) for the targeted compounds in YPF. This integrated strategy improved the efficiency of targeted compound discovery in offline 2D-LC MS data, also shown a huge scalability in accurate compound annotation of complex samples. In conclusion, our study developed available concepts and tools while providing a research paradigm for efficient and rapid compound annotation in complex samples such as TCM prescriptions, with YPF as an example.
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Affiliation(s)
- Haodong Zhu
- International Cooperative Laboratory of Traditional Chinese Medicine Modernization and Innovative Drug Development of Ministry of Education (MOE) of China / Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research / Institute of Traditional Chinese Medicine & Natural Products, College of Pharmacy, Jinan University, Guangzhou 510632, China
| | - Liangliang He
- International Cooperative Laboratory of Traditional Chinese Medicine Modernization and Innovative Drug Development of Ministry of Education (MOE) of China / Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research / Institute of Traditional Chinese Medicine & Natural Products, College of Pharmacy, Jinan University, Guangzhou 510632, China; Guangzhou Key Laboratory of Formula-Pattern of Traditional Chinese Medicine, School of Traditional Chinese Medicine, Jinan University, Guangzhou 510632, China
| | - Wenyong Wu
- National Engineering Research Center of TCM Standardization Technology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China; School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Huifang Duan
- International Cooperative Laboratory of Traditional Chinese Medicine Modernization and Innovative Drug Development of Ministry of Education (MOE) of China / Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research / Institute of Traditional Chinese Medicine & Natural Products, College of Pharmacy, Jinan University, Guangzhou 510632, China
| | - Jiali Chen
- International Cooperative Laboratory of Traditional Chinese Medicine Modernization and Innovative Drug Development of Ministry of Education (MOE) of China / Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research / Institute of Traditional Chinese Medicine & Natural Products, College of Pharmacy, Jinan University, Guangzhou 510632, China
| | - Qiang Xiao
- International Cooperative Laboratory of Traditional Chinese Medicine Modernization and Innovative Drug Development of Ministry of Education (MOE) of China / Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research / Institute of Traditional Chinese Medicine & Natural Products, College of Pharmacy, Jinan University, Guangzhou 510632, China
| | - Pei Lin
- International Cooperative Laboratory of Traditional Chinese Medicine Modernization and Innovative Drug Development of Ministry of Education (MOE) of China / Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research / Institute of Traditional Chinese Medicine & Natural Products, College of Pharmacy, Jinan University, Guangzhou 510632, China
| | - Zifei Qin
- Department of Pharmacy, the First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
| | - Yi Dai
- International Cooperative Laboratory of Traditional Chinese Medicine Modernization and Innovative Drug Development of Ministry of Education (MOE) of China / Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research / Institute of Traditional Chinese Medicine & Natural Products, College of Pharmacy, Jinan University, Guangzhou 510632, China
| | - Wanying Wu
- National Engineering Research Center of TCM Standardization Technology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China; School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing 210023, China.
| | - Liufang Hu
- International Cooperative Laboratory of Traditional Chinese Medicine Modernization and Innovative Drug Development of Ministry of Education (MOE) of China / Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research / Institute of Traditional Chinese Medicine & Natural Products, College of Pharmacy, Jinan University, Guangzhou 510632, China; Guangzhou Key Laboratory of Formula-Pattern of Traditional Chinese Medicine, School of Traditional Chinese Medicine, Jinan University, Guangzhou 510632, China.
| | - Zhihong Yao
- International Cooperative Laboratory of Traditional Chinese Medicine Modernization and Innovative Drug Development of Ministry of Education (MOE) of China / Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research / Institute of Traditional Chinese Medicine & Natural Products, College of Pharmacy, Jinan University, Guangzhou 510632, China; Guangzhou Key Laboratory of Formula-Pattern of Traditional Chinese Medicine, School of Traditional Chinese Medicine, Jinan University, Guangzhou 510632, China.
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Wicht K, Baert M, Schipperges S, von Doehren N, Desmet G, Van Geem KM, de Villiers A, Lynen F. Enhanced Sensitivity in Comprehensive Liquid Chromatography: Overcoming the Dilution Problem in LC × LC via Temperature-Responsive Liquid Chromatography. Anal Chem 2022; 94:16728-16737. [DOI: 10.1021/acs.analchem.2c03300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Kristina Wicht
- Separation Science Group, Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281-S4, B-9000 Ghent, Belgium
| | - Mathijs Baert
- Separation Science Group, Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281-S4, B-9000 Ghent, Belgium
| | - Sonja Schipperges
- Agilent Technologies, Hewlett Packard Street 8, D-76337 Waldbronn, Germany
| | - Norwin von Doehren
- Agilent Technologies, Netherlands BV, NL-4330 EA Middelburg, Netherlands
| | - Gert Desmet
- Department of Chemical Engineering, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussel, Belgium
| | - Kevin M. Van Geem
- Laboratory for Chemical Technology (LCT), Department of Materials, Textiles and Chemical Engineering, Faculty of Engineering & Architecture, Ghent University, Technologiepark 125, B-9052 Zwijnaarde, Belgium
| | - André de Villiers
- Department of Chemistry and Polymer Science, University of Stellenbosch, Private Bag X1, ZA-7602 Matieland, South Africa
| | - Frédéric Lynen
- Separation Science Group, Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281-S4, B-9000 Ghent, Belgium
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3
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Shang Z, Tian Y, Xiong M, Yi Y, Qiao X, Yang Y, Ye M. Characterization of prenylated phenolics in Glycyrrhiza uralensis by offline two-dimensional liquid chromatography/mass spectrometry coupled with mass defect filter. J Pharm Biomed Anal 2022; 220:115009. [PMID: 36029604 DOI: 10.1016/j.jpba.2022.115009] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 08/13/2022] [Accepted: 08/16/2022] [Indexed: 11/18/2022]
Abstract
Prenylated phenolics are an important class of natural products. In this study, an efficient strategy was established to systematically characterize the prenylated phenolics in Glycyrrhiza uralensis, a popular herbal medicine. Firstly, offline two-dimensional liquid chromatography/mass spectrometry (2DLC/MS) coupled with mass defect filter (MDF) technology was used to preliminarily detect 1631 potential prenylated phenolics. Secondly, the tandem mass spectrometry fragmentation features of different types of prenylated phenolics were investigated using 29 reference standards. Diagnostic fragmentations included neutral loss (NL) of 42 Da for the annular type and NL of 56 Da for the catenulate type in the positive ion mode, and NL of 56 Da for A-ring prenyl groups and NL of 69 Da for B-ring prenyl groups in the negative ion mode. As a result, the prenylation types, substitution sites, and adjacent OH and OCH3 substitutions of 320 prenylated phenolics in G. uralensis were rapidly characterized. Moreover, three prenylated dihydrostilbenes were purified from the aerial part of G. uralensis to verify the structural characterizations.
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Affiliation(s)
- Zhanpeng Shang
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, 38 Xueyuan Road, Beijing 100191, China
| | - Yungang Tian
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, 38 Xueyuan Road, Beijing 100191, China
| | - Ming Xiong
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, 38 Xueyuan Road, Beijing 100191, China
| | - Yang Yi
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, 38 Xueyuan Road, Beijing 100191, China
| | - Xue Qiao
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, 38 Xueyuan Road, Beijing 100191, China
| | - Yanfang Yang
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, 38 Xueyuan Road, Beijing 100191, China.
| | - Min Ye
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, 38 Xueyuan Road, Beijing 100191, China; Yunnan Baiyao International Medical Research Center, Peking University, 38 Xueyuan Road, Beijing 100191, China.
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4
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Wang S, Cao J, Deng J, Hou X, Hao E, Zhang L, Yu H, Li P. Chemical characterization of flavonoids and alkaloids in safflower ( Carthamus tinctorius L.) by comprehensive two-dimensional hydrophilic interaction chromatography coupled with hybrid linear ion trap Orbitrap mass spectrometry. Food Chem X 2021; 12:100143. [PMID: 34712950 PMCID: PMC8529507 DOI: 10.1016/j.fochx.2021.100143] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 10/12/2021] [Accepted: 10/14/2021] [Indexed: 10/31/2022] Open
Abstract
Safflower (Carthamus tinctorius L.) is a famous food additive and herbal medicine in China. In the present research, an online comprehensive two-dimensional hydrophilic interaction chromatography coupled to a diode array detector and a hybrid linear ion trap-Orbitrap mass spectrometry (HILIC × HILIC-DAD-ESI/HRMS/MS n ) platform was developed to analyze the flavonoids and alkaloids in safflower. By combining with an XBridge Amide column (150 mm × 4.6 mm, 3.5 μm) and an Ultimate amide column (50 mm × 4.6 mm, 5 μm), the system orthogonality reached 88% and a total of 231 peaks were detected. Altogether 93 compounds, including 75 flavonoids and their glycosides and 10 alkaloids were unambiguously or tentatively identified in both negative and positive ion modes, using accurate mass and MS fragment data. Among them, 5 compounds were discovered and reported from safflower for the first time. The established HILIC × HILIC platform should be a powerful tool for the separation and characterization of complicated matrices in natural herbs.
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Affiliation(s)
- Songsong Wang
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao 999078, China
| | - Jiliang Cao
- College of Pharmacy, Shenzhen Technology University, Shenzhen 518118, China
| | - Jiagang Deng
- Collaborative Innovation Center of Research on Functional Ingredients from Agricultural Residues, Guangxi Key Laboratory of Efficacy Study on Chinese Materia Medica, Guangxi University of Chinese Medicine, Nanning 530200, China
| | - Xiaotao Hou
- Collaborative Innovation Center of Research on Functional Ingredients from Agricultural Residues, Guangxi Key Laboratory of Efficacy Study on Chinese Materia Medica, Guangxi University of Chinese Medicine, Nanning 530200, China
| | - Erwei Hao
- Collaborative Innovation Center of Research on Functional Ingredients from Agricultural Residues, Guangxi Key Laboratory of Efficacy Study on Chinese Materia Medica, Guangxi University of Chinese Medicine, Nanning 530200, China
| | - Lei Zhang
- Laboratory Animal Center, Sichuan Academy of Chinese Medicine Sciences, Chengdu 610041, China
| | - Hua Yu
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao 999078, China
| | - Peng Li
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao 999078, China
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5
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Chapel S, Heinisch S. Strategies to circumvent the solvent strength mismatch problem in online comprehensive two-dimensional liquid chromatography. J Sep Sci 2021; 45:7-26. [PMID: 34525266 DOI: 10.1002/jssc.202100534] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 08/23/2021] [Accepted: 08/24/2021] [Indexed: 11/09/2022]
Abstract
On-line comprehensive two-dimensional liquid chromatography is a powerful technique for the separation of highly complex samples. Due to the addition of the second dimension of separation, impressive peak capacities can be obtained within a reasonable analysis time compared to one-dimensional liquid chromatography. In online comprehensive two-dimensional liquid chromatography, the separation power is maximized by selecting two separation dimensions as orthogonal as possible, which most often requires the combination of different mobile phases and stationary phases. The online transfer of a given solvent from the first dimension to the second dimension may cause severe injection effects in the second dimension, mostly due to solvent strength mismatch. Those injection effects may include peak broadening, peak distortion, peak splitting or breakthrough phenomenon. They are often found to reduce significantly the peak capacity and the peak intensity. To overcome such effects, arising specifically in online comprehensive two-dimensional liquid chromatography, different methods have been developed over the years. In this review, we focused on the most recently reported ones. A critical discussion, supported by a theoretical approach, gives an overview of their advantages and drawbacks.
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Affiliation(s)
- Soraya Chapel
- Université de Lyon, Institut des sciences analytiques, Villeurbanne, France
| | - Sabine Heinisch
- Université de Lyon, Institut des sciences analytiques, Villeurbanne, France
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6
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Qu K, Wang F, Du Z, Wang S, Zhang Z, Shen Y. A novel and sensitive method for determination of amisulpride in human plasma by two-dimensional liquid chromatography. Biomed Chromatogr 2021; 35:e5149. [PMID: 33928659 DOI: 10.1002/bmc.5149] [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: 11/02/2020] [Revised: 02/09/2021] [Accepted: 04/21/2021] [Indexed: 11/06/2022]
Abstract
A novel and sensitive heart-cutting two-dimensional liquid chromatography with ultraviolet detection method (2D-LC-UV) was developed and validated for determination of amisulpride in human plasma. The 2D-LC system consists of a first dimensional (1 D) LC column and a middle transfer column as well as a second-dimensional (2 D) LC column. After simple protein precipitation, the sample was directly injected into the introduction valve of the 2D-LC system. The 1 D column, playing a role of primary separation and preconcentration for complex plasma matrices, transferred the targets to the intermediate column. Following capture of targets on the middle column online, the analytes were transferred to the 2 D separation column by a six-port valve. The 2 D column, avoiding interference from the plasma matrix, completed further separation and quantification. An assistant pump was optimized for primary enrichment as well as final elution in the heart-cutting mode. The analytical time of amisulpride was 7.401 min. The accuracy was between 0.48 and 8.49%, while the intra- and inter-day precisions ranged from 0.9 to 3.1% and from 1.7% to 3.3%, respectively. The linear range of amisulpride was 48.15-2,407.59 ng/ml, while the extraction recovery was 98.7-101.3%. The strategy established in the study, which was successfully applied to therapeutic drug monitoring of amisulpride for routine clinical detection, displays high sensitivity, good repeatability, convenience and low cost.
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Affiliation(s)
- Kankan Qu
- Department of Pharmacy, The Affiliated Wuxi Mental Health Center with Nanjing Medical University, Wuxi Tongren Rehabilitation Hospital, Wuxi, Jiangsu Province, China
| | - Feng Wang
- Department of Pharmacy, the Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Zhiqiang Du
- Department of Pharmacy, The Affiliated Wuxi Mental Health Center with Nanjing Medical University, Wuxi Tongren Rehabilitation Hospital, Wuxi, Jiangsu Province, China
| | - Shushan Wang
- Department of Pharmacy, The Affiliated Wuxi Mental Health Center with Nanjing Medical University, Wuxi Tongren Rehabilitation Hospital, Wuxi, Jiangsu Province, China
| | - Zhongdong Zhang
- Department of Pharmacy, The Affiliated Wuxi Mental Health Center with Nanjing Medical University, Wuxi Tongren Rehabilitation Hospital, Wuxi, Jiangsu Province, China
| | - Yuan Shen
- Department of Pharmacy, The Affiliated Wuxi Mental Health Center with Nanjing Medical University, Wuxi Tongren Rehabilitation Hospital, Wuxi, Jiangsu Province, China
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7
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Cacciola F, Arena K, Mandolfino F, Donnarumma D, Dugo P, Mondello L. Reversed phase versus hydrophilic interaction liquid chromatography as first dimension of comprehensive two-dimensional liquid chromatography systems for the elucidation of the polyphenolic content of food and natural products. J Chromatogr A 2021; 1645:462129. [PMID: 33864987 DOI: 10.1016/j.chroma.2021.462129] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 03/22/2021] [Accepted: 03/25/2021] [Indexed: 12/19/2022]
Abstract
Comprehensive two-dimensional liquid chromatography is a well-established method for the unraveling of very complex real-world samples. With regard to food and natural products such a technique turned out to be a very promising approach due to its high resolving power and improved identification capability, especially in combination with mass spectrometry. In this context, polyphenols comprise a particular complex class of bioactive compounds, due to their nature and content in commonly consumed foodstuffs, making their analysis challenging. The present contribution shows an overview of the two commonly employed approaches used for polyphenol analysis, viz. RP-LC × RP-LC and HILIC × RP-LC. Furthermore, the latest implementations as well as limitations and future perspectives are critically reported.
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Affiliation(s)
- Francesco Cacciola
- Department of Biomedical, Dental, Morphological and Functional Imaging Sciences, University of Messina, 98125 Messina, Italy.
| | - Katia Arena
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, 98168 Messina, Italy
| | - Filippo Mandolfino
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, 98168 Messina, Italy
| | - Danilo Donnarumma
- Chromaleont s.r.l., c/o Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, 98168 Messina, Italy
| | - Paola Dugo
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, 98168 Messina, Italy; Chromaleont s.r.l., c/o Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, 98168 Messina, Italy
| | - Luigi Mondello
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, 98168 Messina, Italy; Chromaleont s.r.l., c/o Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, 98168 Messina, Italy; Department of Sciences and Technologies for Human and Environment, University Campus Bio-Medico of Rome, 00128 Rome, Italy; BeSep s.r.l., c/o Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, 98168 Messina, Italy
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9
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Liu W, Jin X, Yao S, Wang F. Determination of Risperidone and 9-Hydroxyrisperidone in Human Serum by Heart-Cutting Isocratic Two-Dimensional Liquid Chromatography. ANAL LETT 2020. [DOI: 10.1080/00032719.2020.1728291] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Wei Liu
- Department of Pharmacy, Affiliated Guangji Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Xiaoxia Jin
- Department of Pharmacy, Affiliated Guangji Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Shuyong Yao
- Department of Pharmacy, Affiliated Guangji Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Feng Wang
- Department of Pharmacy, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
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10
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Zhou W, Liu Y, Wang J, Guo Z, Shen A, Liu Y, Liang X. Application of two‐dimensional liquid chromatography in the separation of traditional Chinese medicine. J Sep Sci 2019; 43:87-104. [DOI: 10.1002/jssc.201900765] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 10/16/2019] [Accepted: 10/20/2019] [Indexed: 01/19/2023]
Affiliation(s)
- Weijia Zhou
- Key Lab of Separation Science for Analytical ChemistryDalian Institute of Chemical PhysicsChinese Academy of Sciences Dalian P. R. China
- College of Fisheries and Life ScienceDalian Ocean University Dalian P. R. China
| | - Yanming Liu
- Shandong Institute of Food and Drug Control Jinan P. R. China
| | - Jixia Wang
- Key Lab of Separation Science for Analytical ChemistryDalian Institute of Chemical PhysicsChinese Academy of Sciences Dalian P. R. China
| | - Zhimou Guo
- Key Lab of Separation Science for Analytical ChemistryDalian Institute of Chemical PhysicsChinese Academy of Sciences Dalian P. R. China
| | - Aijin Shen
- Key Lab of Separation Science for Analytical ChemistryDalian Institute of Chemical PhysicsChinese Academy of Sciences Dalian P. R. China
| | - Yanfang Liu
- Key Lab of Separation Science for Analytical ChemistryDalian Institute of Chemical PhysicsChinese Academy of Sciences Dalian P. R. China
| | - Xinmiao Liang
- Key Lab of Separation Science for Analytical ChemistryDalian Institute of Chemical PhysicsChinese Academy of Sciences Dalian P. R. China
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11
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Liu W, Shang X, Yao S, Wang F. A novel and nonderivatization method for the determination of valproic acid in human serum by two‐dimensional liquid chromatography. Biomed Chromatogr 2019; 34:e4695. [PMID: 31469425 DOI: 10.1002/bmc.4695] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 08/22/2019] [Accepted: 08/26/2019] [Indexed: 11/07/2022]
Affiliation(s)
- Wei Liu
- Department of PharmacyAffiliated Guangji Hospital of Soochow University Suzhou Jiangsu China
| | - Xiang Shang
- Department of PharmacyAffiliated Guangji Hospital of Soochow University Suzhou Jiangsu China
| | - Shuyong Yao
- Department of PharmacyAffiliated Guangji Hospital of Soochow University Suzhou Jiangsu China
| | - Feng Wang
- Department of Pharmacythe Second Xiangya Hospital of Central South University Changsha Hunan China
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12
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Ji S, Wang S, Xu H, Su Z, Tang D, Qiao X, Ye M. The application of on-line two-dimensional liquid chromatography (2DLC) in the chemical analysis of herbal medicines. J Pharm Biomed Anal 2018; 160:301-313. [PMID: 30114608 DOI: 10.1016/j.jpba.2018.08.014] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Revised: 08/02/2018] [Accepted: 08/07/2018] [Indexed: 11/30/2022]
Abstract
Herbal medicines are complicated chemical systems containing hundreds of small molecules of various polarities, structural types, and contents. Thus far, the chromatographic separation of herbal extracts is still a big challenge. Two-dimensional liquid chromatography (2DLC) has become an attractive separation tool in the past few years. Particularly, a lot of attention has been paid to on-line 2DLC. In this review, we aim to give an overview on applications of on-line 2DLC in the chemical analysis of herbal medicines since 2010. Firstly, classification and general configurations of on-line 2DLC were briefly introduced. Then, we summarized main applications in herbal medicines of heart-cutting 2DLC (LC-LC), comprehensive 2DLC (LC × LC), and their combinations, with emphasis on LC × LC. Mass spectrometry is the most popular detector coupled with 2DLC, which allows sensitive and accurate structural characterization of herbal compounds. Finally, future developments in on-line 2DLC techniques were also discussed.
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Affiliation(s)
- Shuai Ji
- Department of Pharmaceutical Analysis, Xuzhou Medical University, 209 Tongshan Road, Xuzhou 221004, China; State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, 38 Xueyuan Road, Beijing 100191, China
| | - Shuang Wang
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, 38 Xueyuan Road, Beijing 100191, China
| | - Haishan Xu
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, 38 Xueyuan Road, Beijing 100191, China; Civil Aviation Medicine Center & Civil Aviation General Hospital, Civil Aviation Administration of China, A-1 Gaojing, Chaoyang District, Beijing 100123, China
| | - Zhenyu Su
- Department of Pharmaceutical Analysis, Xuzhou Medical University, 209 Tongshan Road, Xuzhou 221004, China
| | - Daoquan Tang
- Department of Pharmaceutical Analysis, Xuzhou Medical University, 209 Tongshan Road, Xuzhou 221004, China
| | - Xue Qiao
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, 38 Xueyuan Road, Beijing 100191, China.
| | - Min Ye
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, 38 Xueyuan Road, Beijing 100191, China.
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Pan H, Yao C, Yang W, Yao S, Huang Y, Zhang Y, Wu W, Guo D. An enhanced strategy integrating offline two-dimensional separation and step-wise precursor ion list-based raster-mass defect filter: Characterization of indole alkaloids in five botanical origins of Uncariae Ramulus Cum Unicis as an exemplary application. J Chromatogr A 2018; 1563:124-134. [PMID: 29880214 DOI: 10.1016/j.chroma.2018.05.066] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Revised: 04/20/2018] [Accepted: 05/28/2018] [Indexed: 01/01/2023]
Abstract
Comprehensive chemical profiling is of great significance for understanding the therapeutic material basis and quality control of herbal medicines, which is challenging due to its inherent chemical diversity and complexity, as well as wide concentration range. In this study, we introduced an enhanced strategy integrating offline two-dimensional (2D) separation and the step-wise precursor ion list-based raster-mass defect filter (step-wise PIL-based raster-MDF) scan by tandem LTQ-Orbitrap mass spectrometer. A comprehensive analysis of indole alkaloids in five botanical origins of Uncariae Ramulus Cum Unicis (Gou-Teng) was used as an exemplary application. A positively charged reversed phase (PR) × conventional RP LC system in different pH conditions was constructed with the orthogonality of 74%. A theoretical step-wise PIL among 310-950 Da with the step-size of 2 Da was developed to selectively trigger fragmentations and extend the coverage of potential indole alkaloids. Simultaneously, by defining parent mass width (PMW) of the step-wise PIL to ±55 mDa, a raster-MDF screening was achieved in the acquisition process. Additionally, subtype classification and structural elucidation were facilitated by a four-step interpretation strategy. As a result, a total of 1227 indole alkaloids were efficiently exposed and characterized from five botanical origins of Gou-Teng, which showed high chemical diversity. A systematic comparison among five species was first performed and only 66 indole alkaloids were common. For method validation, three new alkaloid N-oxides were isolated and unambiguously identified by NMR. The present study provides a novel data-dependent acquisition method with improved target coverage and high selectivity. The integrated strategy is practical to efficiently expose and comprehensively characterize complex components in herbal medicines.
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Affiliation(s)
- Huiqin Pan
- Shanghai Research Center for Modernization of Traditional Chinese Medicine, National Engineering Laboratory for TCM Standardization Technology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences,Haike Road 501, Shanghai, 201203, People's Republic of China; University of Chinese Academy of Sciences,No.19A Yuquan Road, Beijing, 100049, People's Republic of China
| | - Changliang Yao
- Shanghai Research Center for Modernization of Traditional Chinese Medicine, National Engineering Laboratory for TCM Standardization Technology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences,Haike Road 501, Shanghai, 201203, People's Republic of China; University of Chinese Academy of Sciences,No.19A Yuquan Road, Beijing, 100049, People's Republic of China
| | - Wenzhi Yang
- Shanghai Research Center for Modernization of Traditional Chinese Medicine, National Engineering Laboratory for TCM Standardization Technology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences,Haike Road 501, Shanghai, 201203, People's Republic of China
| | - Shuai Yao
- Shanghai Research Center for Modernization of Traditional Chinese Medicine, National Engineering Laboratory for TCM Standardization Technology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences,Haike Road 501, Shanghai, 201203, People's Republic of China
| | - Yong Huang
- Shanghai Research Center for Modernization of Traditional Chinese Medicine, National Engineering Laboratory for TCM Standardization Technology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences,Haike Road 501, Shanghai, 201203, People's Republic of China
| | - Yibei Zhang
- Shanghai Research Center for Modernization of Traditional Chinese Medicine, National Engineering Laboratory for TCM Standardization Technology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences,Haike Road 501, Shanghai, 201203, People's Republic of China
| | - Wanying Wu
- Shanghai Research Center for Modernization of Traditional Chinese Medicine, National Engineering Laboratory for TCM Standardization Technology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences,Haike Road 501, Shanghai, 201203, People's Republic of China.
| | - Dean Guo
- Shanghai Research Center for Modernization of Traditional Chinese Medicine, National Engineering Laboratory for TCM Standardization Technology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences,Haike Road 501, Shanghai, 201203, People's Republic of China.
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14
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Global profiling combined with predicted metabolites screening for discovery of natural compounds: Characterization of ginsenosides in the leaves of Panax notoginseng as a case study. J Chromatogr A 2018; 1538:34-44. [DOI: 10.1016/j.chroma.2018.01.040] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2017] [Revised: 11/17/2017] [Accepted: 01/18/2018] [Indexed: 12/16/2022]
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15
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Wang YQ, Tang X, Li JF, Wu YL, Sun YY, Fang MJ, Wu Z, Wang XM, Qiu YK. Development of an on-line mixed-mode gel liquid chromatography×reversed phase liquid chromatography method for separation of water extract from Flos Carthami. J Chromatogr A 2017; 1519:145-151. [PMID: 28886939 DOI: 10.1016/j.chroma.2017.08.053] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Revised: 05/25/2017] [Accepted: 08/20/2017] [Indexed: 02/02/2023]
Abstract
A novel on-line comprehensive two-dimensional liquid chromatography (2D-LC) method by coupling mixed-mode gel liquid chromatography (MMG-LC) with reversed phase liquid chromatography (RPLC) was developed. A mixture of 17 reference compounds was used to study the separation mechanism. A crude water extract of Flos Carthami was applied to evaluate the performance of the novel 2D-LC system. In the first dimension, the extract was eluted with a gradient of water/methanol over a cross-linked dextran gel Sephadex LH-20 column. Meanwhile, the advantages of size exclusion, reversed phase partition and adsorption separation mechanism were exploited before further on-line reversed phase purification on the second dimension. This novel on-line mixed-mode Sephadex LH-20×RPLC method provided higher peak resolution, sample processing ability (2.5mg) and better orthogonality (72.9%) versus RPLC×RPLC and hydrophilic interaction liquid chromatography (HILIC)×RPLC. To the best of our knowledge, this is the first report of a mixed-mode Sephadex LH-20×RPLC separation method with successful applications in on-line mode, which might be beneficial for harvesting targets from complicated medicinal plants.
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Affiliation(s)
- Yu-Qing Wang
- Fujian Provincial Key Laboratory of Innovative Drug Target Research, School of Pharmaceutical Sciences, Xiamen University, South Xiang-An Road, Xiamen, 361102, China
| | - Xu Tang
- Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography State Oceanic Administration, Xiamen 361005, China
| | - Jia-Fu Li
- Fujian Provincial Key Laboratory of Innovative Drug Target Research, School of Pharmaceutical Sciences, Xiamen University, South Xiang-An Road, Xiamen, 361102, China
| | - Yun-Long Wu
- Fujian Provincial Key Laboratory of Innovative Drug Target Research, School of Pharmaceutical Sciences, Xiamen University, South Xiang-An Road, Xiamen, 361102, China
| | - Yu-Ying Sun
- Fujian Provincial Key Laboratory of Innovative Drug Target Research, School of Pharmaceutical Sciences, Xiamen University, South Xiang-An Road, Xiamen, 361102, China
| | - Mei-Juan Fang
- Fujian Provincial Key Laboratory of Innovative Drug Target Research, School of Pharmaceutical Sciences, Xiamen University, South Xiang-An Road, Xiamen, 361102, China
| | - Zhen Wu
- Fujian Provincial Key Laboratory of Innovative Drug Target Research, School of Pharmaceutical Sciences, Xiamen University, South Xiang-An Road, Xiamen, 361102, China
| | - Xiu-Min Wang
- Fujian Provincial Key Laboratory of Innovative Drug Target Research, School of Pharmaceutical Sciences, Xiamen University, South Xiang-An Road, Xiamen, 361102, China.
| | - Ying-Kun Qiu
- Fujian Provincial Key Laboratory of Innovative Drug Target Research, School of Pharmaceutical Sciences, Xiamen University, South Xiang-An Road, Xiamen, 361102, China.
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16
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Validation of a two-dimensional liquid chromatography method for quality control testing of pharmaceutical materials. J Chromatogr A 2017; 1492:89-97. [PMID: 28284763 DOI: 10.1016/j.chroma.2017.02.074] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Revised: 02/26/2017] [Accepted: 02/28/2017] [Indexed: 11/22/2022]
Abstract
Despite the advantages of 2D-LC, there is currently little to no work in demonstrating the suitability of these 2D-LC methods for use in a quality control (QC) environment for good manufacturing practice (GMP) tests. This lack of information becomes more critical as the availability of commercial 2D-LC instrumentation has significantly increased, and more testing facilities begin to acquire these 2D-LC capabilities. It is increasingly important that the transferability of developed 2D-LC methods be assessed in terms of reproducibility, robustness and performance across different laboratories worldwide. The work presented here focuses on the evaluation of a heart-cutting 2D-LC method used for the analysis of a pharmaceutical material, where a key, co-eluting impurity in the first dimension (1D) is resolved from the main peak and analyzed in the second dimension (2D). A design-of-experiments (DOE) approach was taken in the collection of the data, and the results were then modeled in order to evaluate method robustness using statistical modeling software. This quality by design (QBD) approach gives a deeper understanding of the impact of these 2D-LC critical method attributes (CMAs) and how they affect overall method performance. Although there are multiple parameters that may be critical from method development point of view, a special focus of this work is devoted towards evaluation of unique 2D-LC critical method attributes from method validation perspective that transcend conventional method development and validation. The 2D-LC method attributes are evaluated for their recovery, peak shape, and resolution of the two co-eluting compounds in question on the 2D. In the method, linearity, accuracy, precision, repeatability, and sensitivity are assessed along with day-to-day, analyst-to-analyst, and lab-to-lab (instrument-to-instrument) assessments. The results of this validation study demonstrate that the 2D-LC method is accurate, sensitive, and robust and is ultimately suitable for QC testing with good method transferability.
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17
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Česla P, Křenková J. Fraction transfer process in on-line comprehensive two-dimensional liquid-phase separations. J Sep Sci 2016; 40:109-123. [DOI: 10.1002/jssc.201600921] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Revised: 11/15/2016] [Accepted: 11/20/2016] [Indexed: 01/19/2023]
Affiliation(s)
- Petr Česla
- Faculty of Chemical Technology, Department of Analytical Chemistry; University of Pardubice; Pardubice Czech Republic
| | - Jana Křenková
- Institute of Analytical Chemistry of the CAS; v.v.i.; Brno Czech Republic
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18
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Affiliation(s)
- Dwight R. Stoll
- Department
of Chemistry, Gustavus Adolphus College, Saint Peter, Minnesota 56082, United States
| | - Peter W. Carr
- Department
of Chemistry, University of Minnesota, Minneapolis, Minnesota 55104, United States
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19
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A new method for the determination of peak distribution across a two-dimensional separation space for the identification of optimal column combinations. Anal Bioanal Chem 2016; 408:8079-8088. [PMID: 27624763 DOI: 10.1007/s00216-016-9911-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Revised: 08/22/2016] [Accepted: 08/26/2016] [Indexed: 12/16/2022]
Abstract
For the identification of the optimal column combinations, a comparative orthogonality study of single columns and columns coupled in series for the first dimension of a microscale two-dimensional liquid chromatographic approach was performed. In total, eight columns or column combinations were chosen. For the assessment of the optimal column combination, the orthogonality value as well as the peak distributions across the first and second dimension was used. In total, three different methods of orthogonality calculation, namely the Convex Hull, Bin Counting, and Asterisk methods, were compared. Unfortunately, the first two methods do not provide any information of peak distribution. The third method provides this important information, but is not optimal when only a limited number of components are used for method development. Therefore, a new concept for peak distribution assessment across the separation space of two-dimensional chromatographic systems and clustering detection was developed. It could be shown that the Bin Counting method in combination with additionally calculated histograms for the respective dimensions is well suited for the evaluation of orthogonality and peak clustering. The newly developed method could be used generally in the assessment of 2D separations. Graphical Abstract ᅟ.
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20
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Sun W, Tong L, Miao J, Huang J, Li D, Li Y, Xiao H, Sun H, Bi K. Separation and analysis of phenolic acids from Salvia miltiorrhiza and its related preparations by off-line two-dimensional hydrophilic interaction chromatography × reversed-phase liquid chromatography coupled with ion trap time-of-flight mass spectrometry. J Chromatogr A 2016; 1431:79-88. [DOI: 10.1016/j.chroma.2015.12.038] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Revised: 12/13/2015] [Accepted: 12/15/2015] [Indexed: 12/01/2022]
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21
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Yang W, Si W, Zhang J, Yang M, Pan H, Wu J, Qiu S, Yao C, Hou J, Wu W, Guo D. Selective and comprehensive characterization of the quinochalcone C-glycoside homologs in Carthamus tinctorius L. by offline comprehensive two-dimensional liquid chromatography/LTQ-Orbitrap MS coupled with versatile data mining strategies. RSC Adv 2016. [DOI: 10.1039/c5ra23744k] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
An offline 2D LC/LTQ-Orbitrap MS approach and versatile data mining techniques were developed to characterize new QCGs from C. tinctorius.
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22
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Abstract
This article summarizes the most important developments in the use of 2D-LC for bioanalysis in the last 5 years. While several interesting and powerful applications have been developed recently, this work has been supported by continued, significant development of theoretical concepts, instrument development and practical aspects of method development. Some of the most exciting applications have been focused on the use of 2D-LC and characterize proteins both as biotherapeutic drug substances, and in formulations. These materials are inherently complex, difficult to resolve chromatographically and present problems that are essentially unknown (e.g., aggregation) in the small molecule world, thus 2D-LC can be leveraged very effectively to address these challenges.
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23
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Willemse CM, Stander MA, Vestner J, Tredoux AGJ, de Villiers A. Comprehensive Two-Dimensional Hydrophilic Interaction Chromatography (HILIC) × Reversed-Phase Liquid Chromatography Coupled to High-Resolution Mass Spectrometry (RP-LC-UV-MS) Analysis of Anthocyanins and Derived Pigments in Red Wine. Anal Chem 2015; 87:12006-15. [DOI: 10.1021/acs.analchem.5b03615] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Chandré M. Willemse
- Department
of Chemistry and Polymer Science, Stellenbosch University, Private Bag
X1, Matieland 7602, South Africa
| | - Maria A. Stander
- Central
Analytical Facility, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa
- Department
of Biochemistry, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa
| | - Jochen Vestner
- Center
of Analytical Chemistry and Microbiology, Department of Microbiology
and Biochemistry, Hochschule Geisenheim University, 65366 Geisenheim, Germany
- Université
de Bordeaux, ISVV, EA 4577, Unité de recherche
Œnologie, 33882 Villenave d’Ornon, France
- INRA, ISVV, USC 1366 Œnologie, 33882 Villenave d’Ornon, France
| | - Andreas G. J. Tredoux
- Department
of Chemistry and Polymer Science, Stellenbosch University, Private Bag
X1, Matieland 7602, South Africa
| | - André de Villiers
- Department
of Chemistry and Polymer Science, Stellenbosch University, Private Bag
X1, Matieland 7602, South Africa
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24
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Qiu S, Yang WZ, Shi XJ, Yao CL, Yang M, Liu X, Jiang BH, Wu WY, Guo DA. A green protocol for efficient discovery of novel natural compounds: Characterization of new ginsenosides from the stems and leaves of Panax ginseng as a case study. Anal Chim Acta 2015; 893:65-76. [DOI: 10.1016/j.aca.2015.08.048] [Citation(s) in RCA: 87] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Revised: 08/20/2015] [Accepted: 08/23/2015] [Indexed: 11/24/2022]
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25
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Zimmermann A, Horak J, Sánchez-Muñoz OL, Lämmerhofer M. Surface charge fine tuning of reversed-phase/weak anion-exchange type mixed-mode stationary phases for milder elution conditions. J Chromatogr A 2015. [DOI: 10.1016/j.chroma.2015.07.036] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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26
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Stoll DR, O’Neill K, Harmes DC. Effects of pH mismatch between the two dimensions of reversed-phase × reversed-phase two-dimensional separations on second dimension separation quality for ionogenic compounds—I. Carboxylic acids. J Chromatogr A 2015; 1383:25-34. [DOI: 10.1016/j.chroma.2014.12.054] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Revised: 12/02/2014] [Accepted: 12/18/2014] [Indexed: 10/24/2022]
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27
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Practical considerations in comprehensive two-dimensional liquid chromatography systems (LCxLC) with reversed-phases in both dimensions. Anal Bioanal Chem 2014; 407:153-67. [DOI: 10.1007/s00216-014-8179-8] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Revised: 09/09/2014] [Accepted: 09/10/2014] [Indexed: 12/11/2022]
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