1
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Hubner EM, Schützinger S, Molnárová K, Schmid MG. Screening of Astec® CHIRALDEX™ G-PN and LIPODEX™ D gas chromatography columns for enantioseparation of amphetamine derivatives. Chirality 2024; 36:e23676. [PMID: 38736271 DOI: 10.1002/chir.23676] [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: 11/25/2023] [Revised: 02/17/2024] [Accepted: 04/22/2024] [Indexed: 05/14/2024]
Abstract
Among different substance classes, New Psychoactive Substances (NPS) comprise chiral amphetamines for stimulant and empathic effects. There is little knowledge in terms of clinical studies about possibly different effects of the two enantiomers of novel amphetamine derivatives. For this reason, there is a big demand for enantioseparation method development of this new substance class. Regarding gas chromatography, cyclodextrins proved to be effective for enantioseparation of NPS. In our attempt, an Astec® Chiraldex™ G-PN column containing 2,6-di-O-pentyl-3-propionyl-γ-cyclodextrin and a Lipodex™ D column containing heptakis-(2,6-di-O-pentyl-O-acetyl)-β-cyclodextrin as chiral selector served as stationary phases in a Shimadzu GCMS-QP2010 SE system. Because of the special coating, maximum temperature is limited to 200 °C isothermal or 220 °C in programmed mode. To ensure detection, trifluoroacetic anhydride (TFAA) was used to increase sample volatility.1 As a result, 35 amphetamines were tested as their TFAA-derivatives. A screening method with a temperature gradient from 140 °C to 200 °C at a heating ramp of 1 °C per minute and final time of 5 min, showed baseline separation for seven and partial separations for 16 trifluoro acetylated amphetamines using the Chiraldex™ G-PN column. Six baseline and nine partial separations were observed with the Lipodex™ D column, respectively.
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Affiliation(s)
- Eva-Maria Hubner
- Department of Pharmaceutical Chemistry, Institute of Pharmaceutical Sciences, University of Graz, Graz, Austria
| | - Sophie Schützinger
- Department of Pharmaceutical Chemistry, Institute of Pharmaceutical Sciences, University of Graz, Graz, Austria
| | - Katarína Molnárová
- Department of Analytical Chemistry, Faculty of Science, Charles University of Prague, Praha 2, Czech Republic
| | - Martin G Schmid
- Department of Pharmaceutical Chemistry, Institute of Pharmaceutical Sciences, University of Graz, Graz, Austria
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2
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Dohárszky A, Kalydi E, Völgyi G, Béni S, Fejős I. Cyclodextrin-Enabled Enantioselective Complexation Study of Cathinone Analogs. Molecules 2024; 29:876. [PMID: 38398627 PMCID: PMC10893103 DOI: 10.3390/molecules29040876] [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: 01/12/2024] [Revised: 02/11/2024] [Accepted: 02/12/2024] [Indexed: 02/25/2024] Open
Abstract
The characteristic alkaloid component of the leaves of the catnip shrub (Catha edulis) is cathinone, and its synthetic analogs form a major group of recreational drugs. Cathinone derivatives are chiral compounds. In the literature, several chiral methods using cyclodextrins (CDs) have been achieved so far for diverse sets of analogs; however, a comprehensive investigation of the stability of their CD complexes has not been performed yet. To characterize the enantioselective complex formation, a systematic experimental design was developed in which a total number of 40 neutral, positively, and negatively charged CD derivatives were screened by affinity capillary electrophoresis and compared according to their cavity size, substituent type, and location. The functional groups responsible for the favorable interactions were identified in the case of para-substituted cathinone analog mephedrone, flephedrone, and 4-methylethcathinone (4-MEC) and in the case of 3,4-methylendioxy derivative butylone and methylenedioxypyrovalerone (MDPV). The succinylated-β-CD and subetadex exhibited the highest complex stabilities among the studied drugs. The complex stoichiometry was determined using the Job's plot method, and the complex structures were further studied using ROESY NMR measurements. The results of our enantioselective complex formation study can facilitate chiral method development and may lead to evaluate potential CD-based antidotes for cathinone analogs.
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Affiliation(s)
- András Dohárszky
- Department of Pharmacognosy, Semmelweis University, Üllői út 26, H-1085 Budapest, Hungary; (A.D.); (E.K.)
| | - Eszter Kalydi
- Department of Pharmacognosy, Semmelweis University, Üllői út 26, H-1085 Budapest, Hungary; (A.D.); (E.K.)
- Department of Organic Chemistry, Semmelweis University, Hőgyes Endre utca 7, H-1092 Budapest, Hungary
| | - Gergely Völgyi
- Department of Pharmaceutical Chemistry, Semmelweis University, Hőgyes Endre utca 7, H-1092 Budapest, Hungary;
| | - Szabolcs Béni
- Department of Pharmacognosy, Semmelweis University, Üllői út 26, H-1085 Budapest, Hungary; (A.D.); (E.K.)
- Department of Analytical Chemistry, Institute of Chemistry, ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, H-1117 Budapest, Hungary
| | - Ida Fejős
- Department of Pharmacognosy, Semmelweis University, Üllői út 26, H-1085 Budapest, Hungary; (A.D.); (E.K.)
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3
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Ibrahim AE, El Gohary NA, Aboushady D, Samir L, Karim SEA, Herz M, Salman BI, Al-Harrasi A, Hanafi R, El Deeb S. Recent advances in chiral selectors immobilization and chiral mobile phase additives in liquid chromatographic enantio-separations: A review. J Chromatogr A 2023; 1706:464214. [PMID: 37506464 DOI: 10.1016/j.chroma.2023.464214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 07/10/2023] [Accepted: 07/11/2023] [Indexed: 07/30/2023]
Abstract
For decades now, the separation of chiral enantiomers of drugs has been gaining the interest and attention of researchers. In 1991, the first guidelines for development of chiral drugs were firstly released by the US-FDA. Since then, the development in chromatographic enantioseparation tools has been fast and variable, aiming at creating a suitable environment where the physically and chemically identical enantiomers can be separated. Among those tools, the immobilization of chiral selectors (CS) on different stationary phases and the chiral mobile phase additives (CMPA) which have been progressed and studied extensively. This review article highlights the major advances in immobilization of CS together with their different recognition mechanisms as well as CMPA as a cheaper and successful alternative for chiral stationary phases. Moreover, the role of molecular modeling tool as a pre-step in the choice of CS for evaluating possible interactions with different ligands has been pointed up. Illustrations of reported methods and updates for immobilized CS and CMPA have been included.
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Affiliation(s)
- Adel Ehab Ibrahim
- Pharmaceutical Analytical Chemistry Department, Faculty of Pharmacy, Port-Said University, Port-Said 42511, Egypt; Natural and Medical Sciences Research Center, University of Nizwa, P.O. Box 33, Birkat Al Mauz, Nizwa 616, Sultanate of Oman
| | - Nesrine Abdelrehim El Gohary
- Pharmaceutical Chemistry Department, Faculty of Pharmacy and Biotechnology, German University in Cairo, Cairo 11835, Egypt
| | - Dina Aboushady
- Pharmaceutical Chemistry Department, Faculty of Pharmacy and Biotechnology, German University in Cairo, Cairo 11835, Egypt
| | - Liza Samir
- Pharmaceutical Chemistry Department, Faculty of Pharmacy and Biotechnology, German University in Cairo, Cairo 11835, Egypt
| | - Shereen Ekram Abdel Karim
- Pharmaceutical Chemistry Department, Faculty of Pharmacy and Biotechnology, German University in Cairo, Cairo 11835, Egypt
| | - Magy Herz
- Pharmaceutical Chemistry Department, Faculty of Pharmacy and Biotechnology, German University in Cairo, Cairo 11835, Egypt
| | - Baher I Salman
- Pharmaceutical Analytical Chemistry Department, Faculty of Pharmacy, Al-Azhar University, Assiut Branch, Assiut, 71524, Egypt
| | - Ahmed Al-Harrasi
- Natural and Medical Sciences Research Center, University of Nizwa, P.O. Box 33, Birkat Al Mauz, Nizwa 616, Sultanate of Oman
| | - Rasha Hanafi
- Pharmaceutical Chemistry Department, Faculty of Pharmacy and Biotechnology, German University in Cairo, Cairo 11835, Egypt
| | - Sami El Deeb
- Institute of Medicinal and Pharmaceutical Chemistry, Technische Universität Braunschweig, Braunschweig 38092, Germany; Institute of Pharmacy, Freie Universität Berlin, Königin-Luise-Str. 2+4, 14195 Berlin, Germany.
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4
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Al-Sulaimi S, Kushwah R, Abdullah Alsibani M, El Jery A, Aldrdery M, Ashraf GA. Emerging Developments in Separation Techniques and Analysis of Chiral Pharmaceuticals. Molecules 2023; 28:6175. [PMID: 37687004 PMCID: PMC10489017 DOI: 10.3390/molecules28176175] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 08/05/2023] [Accepted: 08/14/2023] [Indexed: 09/10/2023] Open
Abstract
Chiral separation, the process of isolating enantiomers from a racemic mixture, holds paramount importance in diverse scientific disciplines. Using chiral separation methods like chromatography and electrophoresis, enantiomers can be isolated and characterized. This study emphasizes the significance of chiral separation in drug development, quality control, environmental analysis, and chemical synthesis, facilitating improved therapeutic outcomes, regulatory compliance, and enhanced industrial processes. Capillary electrophoresis (CE) has emerged as a powerful technique for the analysis of chiral drugs. This review also highlights the significance of CE in chiral drug analysis, emphasizing its high separation efficiency, rapid analysis times, and compatibility with other detection techniques. High-performance liquid chromatography (HPLC) has become a vital technique for chiral drugs analysis. Through the utilization of a chiral stationary phase, HPLC separates enantiomers based on their differential interactions, allowing for the quantification of individual enantiomeric concentrations. This study also emphasizes the significance of HPLC in chiral drug analysis, highlighting its excellent resolution, sensitivity, and applicability. The resolution and enantiomeric analysis of nonsteroidal anti-inflammatory drugs (NSAIDs) hold great importance due to their chiral nature and potential variations in pharmacological effects. Several studies have emphasized the significance of resolving and analyzing the enantiomers of NSAIDs. Enantiomeric analysis provides critical insights into the pharmacokinetics, pharmacodynamics, and potential interactions of NSAIDs, aiding in drug design, optimization, and personalized medicine for improved therapeutic outcomes and patient safety. Microfluidics systems have revolutionized chiral separation, offering miniaturization, precise fluid control, and high throughput. Integration of microscale channels and techniques provides a promising platform for on-chip chiral analysis in pharmaceuticals and analytical chemistry. Their applications in techniques such as high-performance liquid chromatography (HPLC) and capillary electrochromatography (CEC) offer improved resolution and faster analysis times, making them valuable tools for enantiomeric analysis in pharmaceutical, environmental, and biomedical research.
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Affiliation(s)
- Sulaiman Al-Sulaimi
- Department of Biological Science and Chemistry, University of Nizwa, Nizwa 611, Oman; (S.A.-S.); (R.K.); (M.A.A.)
| | - Reveka Kushwah
- Department of Biological Science and Chemistry, University of Nizwa, Nizwa 611, Oman; (S.A.-S.); (R.K.); (M.A.A.)
| | - Mohammed Abdullah Alsibani
- Department of Biological Science and Chemistry, University of Nizwa, Nizwa 611, Oman; (S.A.-S.); (R.K.); (M.A.A.)
| | - Atef El Jery
- Department of Chemical Engineering, College of Engineering, King Khalid University, Abha 61411, Saudi Arabia
| | - Moutaz Aldrdery
- Department of Chemical Engineering, College of Engineering, King Khalid University, Abha 61411, Saudi Arabia
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5
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Dobšíková K, Javorská Ž, Paškan M, Spálovská D, Trembulaková P, Herciková J, Kuchař M, Kozmík V, Kohout M, Setnička V. Enantioseparation and a comprehensive spectroscopic analysis of novel synthetic cathinones laterally substituted with a trifluoromethyl group. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2023; 291:122320. [PMID: 36634495 DOI: 10.1016/j.saa.2023.122320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 12/20/2022] [Accepted: 01/02/2023] [Indexed: 06/17/2023]
Abstract
Recently, the number of structural modifications of synthetic cathinones has been growing making them the second largest group of new psychoactive substances in Europe. Although they are abused because of their various psychoactive effects, some compounds from this group also serve as pharmaceuticals. Since synthetic cathinones are chiral molecules with one chiral center, their biological, toxicological, and pharmacological properties may significantly differ according to their absolute configuration and enantiomeric excess. In this study, we have synthesized two substances bearing a pharmacologically interesting trifluoromethyl group and developed a chiral liquid chromatography method using a polysaccharide chiral stationary phase to separate the corresponding enantiomers of both these drugs. Subsequently, we utilized molecular spectroscopic methods including chiroptical (electronic circular dichroism and vibrational circular dichroism) and non-polarizable (infrared and ultraviolet absorption) spectroscopies. In combination with density functional theory calculations, we have obtained stable conformers of selected enantiomers in solution and their relative abundances, which we used to simulate their spectra. The experimental and calculated data have been used to elucidate the 3D structure of the enantiomerically pure compounds and assign the absolute configuration of all prepared compounds.
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Affiliation(s)
- K Dobšíková
- Department of Analytical Chemistry, University of Chemistry and Technology, Technická 5, Prague 6 166 28, Czech Republic
| | - Ž Javorská
- Department of Organic Chemistry, University of Chemistry and Technology, Technická 5, Prague 6 166 28, Czech Republic
| | - M Paškan
- Department of Organic Chemistry, University of Chemistry and Technology, Technická 5, Prague 6 166 28, Czech Republic
| | - D Spálovská
- Department of Analytical Chemistry, University of Chemistry and Technology, Technická 5, Prague 6 166 28, Czech Republic
| | - P Trembulaková
- Department of Analytical Chemistry, University of Chemistry and Technology, Technická 5, Prague 6 166 28, Czech Republic
| | - J Herciková
- Department of Organic Chemistry, University of Chemistry and Technology, Technická 5, Prague 6 166 28, Czech Republic
| | - M Kuchař
- Forensic Laboratory of Biologically Active Substances, Department of Chemistry of Natural Compounds, University of Chemistry and Technology, Technická 5, Prague 6 166 28, Czech Republic; Psychedelic Research Centre, National Institute of Mental Health, Topolová 748, 250 67 Klecany, Czech Republic
| | - V Kozmík
- Department of Organic Chemistry, University of Chemistry and Technology, Technická 5, Prague 6 166 28, Czech Republic
| | - M Kohout
- Department of Organic Chemistry, University of Chemistry and Technology, Technická 5, Prague 6 166 28, Czech Republic
| | - V Setnička
- Department of Analytical Chemistry, University of Chemistry and Technology, Technická 5, Prague 6 166 28, Czech Republic.
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6
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Recent Advances on Chiral Mobile Phase Additives: A Critical Review. JOURNAL OF ANALYSIS AND TESTING 2022. [DOI: 10.1007/s41664-022-00222-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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7
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Terashima H, Seki M, Saki W, Yamamoto A, Aizawa SI, Taga A, Mikami I, Kodama S. Chiral separation of catechin and epicatechin by reversed phase high-performance liquid chromatography with β-cyclodextrin stepwise and linear gradient elution modes. J Chromatogr A 2022; 1673:463029. [DOI: 10.1016/j.chroma.2022.463029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Revised: 04/01/2022] [Accepted: 04/04/2022] [Indexed: 10/18/2022]
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8
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Synthetic Cathinones: Recent Developments, Enantioselectivity Studies and Enantioseparation Methods. Molecules 2022; 27:molecules27072057. [PMID: 35408456 PMCID: PMC9000803 DOI: 10.3390/molecules27072057] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 03/16/2022] [Accepted: 03/18/2022] [Indexed: 11/17/2022] Open
Abstract
New psychoactive substances represent a public health threat since they are not controlled by international conventions, are easily accessible online and are sold as a legal alternative to illicit drugs. Among them, synthetic cathinones are widely abused due to their stimulant and hallucinogenic effects. To circumvent the law, new derivatives are clandestinely synthesized and, therefore, synthetic cathinones keep emerging on the drug market, with their chemical and toxicological properties still unknown. In this review, a literature assessment about synthetic cathinones is presented focusing on the recent developments, which include more than 50 derivatives since 2014. A summary of their toxicokinetic and toxicodynamic properties are also presented. Furthermore, synthetic cathinones are chiral compounds, meaning that they can exist as two enantiomeric forms which may present different biological and toxicological activities. To analyze the enantiomers, the development of enantiomeric resolution methods for synthetic cathinones is crucial. Many methods have been reported over the years that include mostly chromatographic and electromigration techniques, with liquid chromatography using chiral stationary phases being the technique of choice. This review intended to present an overview of enantioselectivity studies and enantioseparation analysis regarding synthetic cathinones, highlighting the relevance of chirality and current trends.
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Sun G, Tang W, Lu Y, Row KH. Enantioseparation by simultaneous biphasic recognition using mobile phase additive and chiral stationary phase in capillary electrochromatography. J Chromatogr A 2022; 1666:462856. [DOI: 10.1016/j.chroma.2022.462856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2021] [Revised: 01/21/2022] [Accepted: 01/25/2022] [Indexed: 10/19/2022]
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10
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Terashima H, Yamamoto A, Aizawa SI, Taga A, Mikami I, Ishihara Y, Kodama S. Enantioseparation of phenethylamines by using high-performance liquid chromatography column permanently coated with methylated β-cyclodextrin. J Sep Sci 2021; 44:2932-2940. [PMID: 34077621 DOI: 10.1002/jssc.202100343] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 05/28/2021] [Accepted: 05/29/2021] [Indexed: 01/13/2023]
Abstract
Cyclodextrins and their derivatives have been used for chiral high-performance liquid chromatography selectors, while they are costly to use as mobile phase additives in high-performance liquid chromatography. Here, we report application of phenyl column coated permanently with methylated β-cyclodextrin for chiral high-performance liquid chromatography. A 0.1% (v/v) phosphoric acid solution containing 1 M NaCl and 0.5% (w/v) methylated β-cyclodextrin was subjected to a phenyl column at a flow rate of 0.5 mL/min at 30°C for 2 h. Using the precoating phenyl column, all the enantiomers of the four phenethylamines (norepinephrine, epinephrine, octopamine, and synephrine) were successfully separated simultaneously by high-performance liquid chromatography with a mobile phase without methylated β-cyclodextrin at a flow rate of 0.2 mL/min at 30°C. The enantioseparation ability was retained for successive analyses during 1 week. It is suggested that inclusion complex of methylated β-cyclodextrin with a phenyl group on the surface of the stationary phase could be formed and that the inclusion complex could form the ternary complex with the injected analytes. The longer retention time of (S)-enantiomers of analytes than corresponding (R)-enantiomers for high-performance liquid chromatography could be explained from the higher stability of the methylated β-cyclodextrin complexes with (S)-enantiomers, which were confirmed by capillary electrophoresis and 1 H NMR spectroscopy experiments.
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Affiliation(s)
| | - Atsushi Yamamoto
- Department of Biological Chemistry, College of Bioscience and Biotechnology, Chubu University, Aichi, Japan
| | | | - Atsushi Taga
- Faculty of Pharmacy, Kindai University, Higashi-Osaka, Japan
| | - Ikko Mikami
- School of Science, Tokai University, Hiratsuka, Japan
| | | | - Shuji Kodama
- School of Science, Tokai University, Hiratsuka, Japan
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11
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Varfaj I, Protti M, Cirrincione M, Carotti A, Mercolini L, Sardella R. Original enantioseparation of illicit fentanyls with cellulose-based chiral stationary phases under polar-ionic conditions. J Chromatogr A 2021; 1643:462088. [PMID: 33784502 DOI: 10.1016/j.chroma.2021.462088] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 03/16/2021] [Accepted: 03/19/2021] [Indexed: 10/21/2022]
Abstract
Fentanyl analogues used in therapy and a range of highly potent non-pharmaceutical fentanyl derivatives are subject to international control, as the latter are increasingly being synthesized illicitly and sold as 'synthetic heroin', or mixed with heroin. A significant number of hospitalizations and deaths have been reported in the EU and USA following the use of illicitly synthesized fentanyl derivatives. It has been unequivocally demonstrated that the enantiomers of fentanyl derivatives exhibit different pharmaco-toxicological profiles, which makes crucial to avail of suitable analytical methods enabling investigations at a "stereochemical level". Chromatographic methods useful to discriminate the enantioseparation of fentanyls and their derivatives are still missing in the literature. This is the first study in which the enantioseparation of four fentanyl derivatives, that is, (±)-trans-3-methyl norfentanyl, (±)-cis-3-methyl norfentanyl, β-hydroxyfentanyl, and β-hydroxythiofentanyl, has been obtained under polar-ionic conditions. Indeed, the use of ACN-based mobile phases with minor amounts of either 2-propanol or ethanol (plus diethylamine and formic acid as ionic additives) allowed obtaining enantioseparation and enantioresolution factors up to 1.83 and 7.02, respectively. For the study, the two chiral stationary phases cellulose tris(3-chloro-4-methylphenylcarbamate) and cellulose tris(4-chloro-3-methylphenylcarbamate) were used, displaying a remarkably different performance towards the enantioseparation of (±)-cis-3-methyl norfentanyl. Chiral LC analyses with a high-resolution mass spectrometry detector were also carried out in order to confirm the obtained data and demonstrate the suitability and compatibility of the optimized mobile phases with mass spectrometric systems.
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Affiliation(s)
- Ina Varfaj
- Department of Pharmaceutical Sciences, University of Perugia, Via Fabretti 48, 06123 Perugia, Italy
| | - Michele Protti
- Department of Pharmacy and Biotechnology (FaBiT), Alma Mater Studiorum, University of Bologna, Via Belmeloro 6, 40126 Bologna
| | - Marco Cirrincione
- Department of Pharmacy and Biotechnology (FaBiT), Alma Mater Studiorum, University of Bologna, Via Belmeloro 6, 40126 Bologna
| | - Andrea Carotti
- Department of Pharmaceutical Sciences, University of Perugia, Via Fabretti 48, 06123 Perugia, Italy
| | - Laura Mercolini
- Department of Pharmacy and Biotechnology (FaBiT), Alma Mater Studiorum, University of Bologna, Via Belmeloro 6, 40126 Bologna.
| | - Roccaldo Sardella
- Department of Pharmaceutical Sciences, University of Perugia, Via Fabretti 48, 06123 Perugia, Italy; Center for Perinatal and Reproductive Medicine, University of Perugia, Santa Maria della Misericordia University Hospital, 06132 Perugia, Italy.
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12
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TANG W, CHANG J, WANG Y, WANG A, WANG R. [Research progress on chiral separation of amphetamines, ketamine, cathinones]. Se Pu 2021; 39:271-280. [PMID: 34227308 PMCID: PMC9403806 DOI: 10.3724/sp.j.1123.2020.05020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Indexed: 11/25/2022] Open
Abstract
Enantiomers are ubiquitous in nature, and they are especially important in the field of pharmaceutical chemistry. Although the enantiomers of chiral drugs have identical chemical structures, they differ notably in their pharmacological, toxicological, pharmacokinetic, metabolic, and other biological activities. The same is true for amphetamines, ketamine, and cathinones, as the chiral separation of these three drugs is representative of drugs. Gas chromatography (GC), high performance liquid chromatography (HPLC), and capillary electrophoresis (CE) are widely used for the chiral separation of these three kinds of drugs. There are some similarities among the three methods for the chiral separation of amphetamines, ketamine, and cathinones: n-trifluoroacetyl-L-prolinyl chloride and (+)R-α-methoxy-α-trifluoromethylphenylacetic acid are the two typical chiral derivatization reagents used in GC. In HPLC, three kinds of chiral stationary phases are used: proteins, polysaccharides, and macrocyclic antibiotics. Cyclodextrin and its derivatives are most commonly used in CE. However, these three methods have inherent shortcomings. In the case of GC, impurities produced during chiral derivatization may interfere with the analysis, and high reaction temperatures affect the efficiency of chiral separation. HPLC has limited application scope and is expensive. In CE, there has no established process to determine the appropriate chiral selector. In recent years, research into application of the chiral separation of the above-mentioned three kinds of drugs has its own characteristics in forensic toxicology. The chiral separation of amphetamine drugs is mostly used to infer the prototype and synthesis route of drugs on the market. The chiral separation of ketamine involves a variety of biological samples. For cathinones, chiral separation methods emphasize their wide applicability. In this review, 66 reports published in professional local and overseas magazines during the past decade are collated. The characteristics of the enantiomers of amphetamines, ketamine, and cathinones as well as the mechanism of chiral recognition are briefly introduced. The commonness of the research and the application of chiral separation in forensic toxicology are reviewed. This paper proposes that the chiral separation of drugs can be further investigated from the following three aspects: 1) the use of computer technology to establish a molecular model for exploring the mechanism of chiral recognition; 2) developing new technologies for chiral separation and carrying out commercial research on the supercritical fluid method; 3) applying chiral separation to judicial practice, pharmaceutical research and development, and other practical fields.
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13
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Lin HR, Kuo FW. Determination of the R- and S-enantiomers of methylone and ethylone in seized drugs by enantioselective liquid chromatography tandem mass spectrometry analysis. Forensic Sci Int 2020; 317:110528. [DOI: 10.1016/j.forsciint.2020.110528] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 09/19/2020] [Accepted: 09/24/2020] [Indexed: 10/23/2022]
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14
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Application of chiral chromatography in radiopharmaceutical fields: A review. J Chromatogr A 2020; 1632:461611. [PMID: 33086153 DOI: 10.1016/j.chroma.2020.461611] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 10/07/2020] [Accepted: 10/08/2020] [Indexed: 01/20/2023]
Abstract
Chiral column chromatography (CCC) is a revolutionary analytical methodology for the enantioseparation of novel positron emission tomography (PET) tracers in the primary stages of drug development. Due to the different behaviors of tracer enantiomers (e.g. toxicity, metabolism and side effects) in administrated subjects, their separation and purification is a challenging endeavor. Over the last three decades, different commercial chiral columns have been applied for the enantioseparation of PET-radioligand (PET-RL) or radiotracers (PET-RT), using high-performance liquid chromatography (HPLC). The categorization and reviewing of them is a vital topic. This review presents a brief overview of advances, applications, and future prospectives of CCC in radiopharmaceutical approaches. In addition, the effective chromatographic parameters and degravitation trends to enhance enantioseparation resolution are addressed. Moreover, the application and potential of chiral super fluidical chromatography (CSFC) as an alternative for enantioseparation in the field of radiopharmaceutical is discussed. Finally, the crucial application challenges of CCC are explained and imminent tasks are suggested.
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15
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Schmid MG, Hägele JS. Separation of enantiomers and positional isomers of novel psychoactive substances in solid samples by chromatographic and electrophoretic techniques – A selective review. J Chromatogr A 2020; 1624:461256. [DOI: 10.1016/j.chroma.2020.461256] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 05/13/2020] [Accepted: 05/15/2020] [Indexed: 10/24/2022]
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16
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Gradient supercritical fluid chromatography coupled to mass spectrometry with a gradient flow of make-up solvent for enantioseparation of cathinones. J Chromatogr A 2020; 1625:461286. [DOI: 10.1016/j.chroma.2020.461286] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Revised: 05/27/2020] [Accepted: 05/29/2020] [Indexed: 12/17/2022]
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17
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Hägele JS, Hubner E, Schmid MG. Determination of the chiral status of different novel psychoactive substance classes by capillary electrophoresis and β-cyclodextrin derivatives. Chirality 2020; 32:1191-1207. [PMID: 32671883 PMCID: PMC7496848 DOI: 10.1002/chir.23268] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 06/19/2020] [Accepted: 07/01/2020] [Indexed: 01/29/2023]
Abstract
Besides the abuse of well‐known illicit drugs, consumers discovered new synthetic compounds with similar effects but minor alterations in their chemical structure. Originally, these so‐called novel psychoactive substances (NPS) have been created to circumvent law of prosecution because of illicit drug abuse. During the past decade, such compounds came up in generations, the most popular compound was a synthetic cathinone derivative named mephedrone. Cathinones are structurally related to amphetamines; to date, more than 120 completely new derivatives have been synthesized and are traded via the Internet. Cathinones possess a chiral center; however, only little is known about the pharmacology of their enantiomers. However, NPS comprise further chiral compound classes such as amphetamine derivatives, ketamines, 2‐(aminopropyl)benzofurans, and phenidines. In continuation of our project, a cheap and easy‐to‐perform chiral capillary zone electrophoresis method for enantioseparation of cathinones presented previously was extended to the aforementioned compound classes. Enantioresolution was achieved by simply adding native β‐cyclodextrin, acetyl‐β‐cyclodextrin, 2‐hydroxypropyl‐β‐cyclodextrin, or carboxymethyl‐β‐cyclodextrin as chiral selector additives to the background electrolyte. Fifty‐one chiral NPS served as analytes mainly purchased from online vendors via the Internet. Using 10 mM of the aforementioned β‐cyclodextrins in a 10 mM sodium phosphate buffer (pH 2.5), overall, 50 of 51 NPS were resolved. However, chiral separation ability of the selectors differed depending on the analyte. Additionally, simultaneous enantioseparations, the determination of enantiomeric migration orders of selected analytes, and a repeatability study were performed successfully. It was proven that all separated NPS were traded as racemic mixtures.
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Affiliation(s)
- Johannes S. Hägele
- Department of Pharmaceutical Chemistry, Institute of Pharmaceutical SciencesUniversity of GrazGrazAustria
| | - Eva‐Maria Hubner
- Department of Pharmaceutical Chemistry, Institute of Pharmaceutical SciencesUniversity of GrazGrazAustria
| | - Martin G. Schmid
- Department of Pharmaceutical Chemistry, Institute of Pharmaceutical SciencesUniversity of GrazGrazAustria
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18
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Řezanka P, Macková D, Jurok R, Himl M, Kuchař M. Enantioseparation and Determination of Mephedrone and Its Metabolites by Capillary Electrophoresis Using Cyclodextrins as Chiral Selectors. Molecules 2020; 25:molecules25122879. [PMID: 32585814 PMCID: PMC7355680 DOI: 10.3390/molecules25122879] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Revised: 06/15/2020] [Accepted: 06/19/2020] [Indexed: 12/24/2022] Open
Abstract
Mephedrone, a psychoactive compound derived from cathinone, is widely used as a designer drug. The determination of mephedrone and its metabolites is important for understanding its possible use in medicine. In this work, a method of capillary electrophoresis for the chiral separation of mephedrone and its metabolites was developed. Carboxymethylated β-cyclodextrin was selected as the most effective chiral selector from seven tested cyclodextrin derivates. Based on the simplex method, the optimal composition of the background electrolyte was determined: at pH 2.75 and 7.5 mmol·L-1 carboxymethylated β-cyclodextrin the highest total resolution of a mixture of analytes was achieved. For mephedrone and its metabolites, calibration curves were constructed in a calibration range from 0.2 to 5 mmol·L-1; limits of detection, limits of quantification, precision, and repeatability were calculated, and according to Mandel's fitting test, the linear calibration ranges were determined.
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Affiliation(s)
- Pavel Řezanka
- Department of Analytical Chemistry, Faculty of Chemical Engineering, University of Chemistry and Technology, Prague, Technická 5, 166 28 Prague 6, Czech Republic;
- Correspondence:
| | - Denisa Macková
- Department of Analytical Chemistry, Faculty of Chemical Engineering, University of Chemistry and Technology, Prague, Technická 5, 166 28 Prague 6, Czech Republic;
| | - Radek Jurok
- Department of Chemistry of Natural Compounds, Forensic Laboratory of Biologically Active Substances, Faculty of Food and Biochemical Technology, University of Chemistry and Technology, Prague, Technická 5, 166 28 Prague 6, Czech Republic; (R.J.); (M.K.)
- Department of Organic Chemistry, Faculty of Chemical Technology, University of Chemistry and Technology, Prague, Technická 5, 166 28 Prague 6, Czech Republic;
| | - Michal Himl
- Department of Organic Chemistry, Faculty of Chemical Technology, University of Chemistry and Technology, Prague, Technická 5, 166 28 Prague 6, Czech Republic;
| | - Martin Kuchař
- Department of Chemistry of Natural Compounds, Forensic Laboratory of Biologically Active Substances, Faculty of Food and Biochemical Technology, University of Chemistry and Technology, Prague, Technická 5, 166 28 Prague 6, Czech Republic; (R.J.); (M.K.)
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19
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Watanabe Y, Mikami I, Yamamoto A, Aizawa SI, Taga A, Mochizuki N, Ishihara Y, Kodama S. Direct enantioseparation of mandelic acid by high-performance liquid chromatography using a phenyl column precoated with a small amount of cyclodextrin additive in a mobile phase. Chirality 2020; 32:1020-1029. [PMID: 32346918 DOI: 10.1002/chir.23228] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 03/23/2020] [Accepted: 04/01/2020] [Indexed: 12/17/2022]
Abstract
Direct enantioseparation of mandelic acid by high-performance liquid chromatography (HPLC) with a reversed phase column and a mobile phase containing a small amount of hydroxylpropyl-β-cyclodextrin (HP-β-CD) was studied as an efficient method for saving consumption of the CD additive. As a result, it was proposed that racemic mandelic acid can be analyzed with a phenyl column by using a mobile phase composed of 10 mM ammonium acetate buffer (pH 4.2) and 0.02% (w/v) HP-β-CD at a flow rate of 1.0 mL/min at 40°C after the passage of 10 mM ammonium acetate buffer (pH 4.2) containing 0.1% (w/v) HP-β-CD as a precoating mobile phase for 60 min. It is suggested that HP-β-CD is bound with a phenyl group on the surface of the stationary phase to allow a phenyl column to act as a transient chiral column, and injected mandelic acid can form the ternary complex with the adsorbed HP-β-CD. The longer retention time of D-mandelic acid than the L-isomer for HPLC can be explained from the higher stability of the HP-β-CD complex with D-mandelic acid, which was confirmed by CE experiment with HP-β-CD as a selector. The efficiency of a phenyl column compared with other stationary phases was also discussed.
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Affiliation(s)
- Yuri Watanabe
- School of Science, Tokai University, Hiratsuka, Japan
| | - Ikko Mikami
- School of Science, Tokai University, Hiratsuka, Japan
| | - Atsushi Yamamoto
- Department of Biological Chemistry, College of Bioscience and Biotechnology, Chubu University, Kasugai-shi, Japan
| | | | - Atsushi Taga
- Department of Pharmacy, Kindai University, Higashi-Osaka, Japan
| | - Naoki Mochizuki
- Department of Health Medicine, Yokohama University of Pharmacy, Yokohama, Japan
| | | | - Shuji Kodama
- School of Science, Tokai University, Hiratsuka, Japan
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20
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Biodistribution and metabolic profile of 3,4-dimethylmethcathinone (3,4-DMMC) in Wistar rats through gas chromatography–mass spectrometry (GC–MS) analysis. Toxicol Lett 2020; 320:113-123. [DOI: 10.1016/j.toxlet.2019.10.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 09/26/2019] [Accepted: 10/10/2019] [Indexed: 11/23/2022]
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21
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Hägele JS, Basrak M, Schmid MG. Enantioselective separation of Novel Psychoactive Substances using a Lux® AMP 3 μm column and HPLC-UV. J Pharm Biomed Anal 2020; 179:112967. [DOI: 10.1016/j.jpba.2019.112967] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Revised: 10/29/2019] [Accepted: 10/31/2019] [Indexed: 01/11/2023]
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22
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Hägele JS, Seibert E, Schmid MG. A Simple HPLC–UV Approach for Rapid Enantioseparation of Cathinones, Pyrovalerones and Other Novel Psychoactive Substances on a 2.5-µm Cellulose Tris-(3,5-dimethylphenyl-carbamate) Column. Chromatographia 2020. [DOI: 10.1007/s10337-020-03860-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
AbstractThe misuse of so called novel psychoactive substances is still a challenging problem worldwide. A special attribute of a lot of these compounds is a chiral centre enabling two possible enantiomers probably related to different pharmacological and toxicological properties. The goal of the present study was to present a simple and isocratic HPLC–UV method for enantioseparation of mainly cathinone and pyrovalerone derivatives as well as selected representatives of amphetamines, ketamines, benzofuries, phenidines, phenidates, morpholines and thiophenes. A Waters Acquity UPC2® Trefoil™ CEL1 2.5 µm, 3.0 × 150 mm column served as chiral stationary phase by means of cellulose tris-(3,5-dimethylphenylcarbamate) as chiral selector. Mobile phases consisted either of n-hexane/n-butanol/diethylamine (100:0.3:0.2) or n-hexane/diethylamine (100:0.2). The method was found to be applicable for rapid simultaneous chiral separations of cathinone derivatives, to determine enantiomeric elution orders, to detect positional isomers and to identify real-life samples. Also, a repeatability study was performed successfully. 78 out of 95 compounds were separated in their enantiomers successfully, 51 of them within 6 min. It was shown that all NPS bought from online vendors or seized by police were traded as racemic mixtures.
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23
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Pharmacokinetics, pharmacodynamics, and toxicity of the new psychoactive substance 3,4-dimethylmethcathinone (3,4-DMMC). Forensic Toxicol 2019. [DOI: 10.1007/s11419-019-00494-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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24
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Hägele JS, Hubner E, Schmid MG. Chiral separation of cathinone derivatives using β-cyclodextrin-assisted capillary electrophoresis-Comparison of four different β-cyclodextrin derivatives used as chiral selectors. Electrophoresis 2019; 40:1787-1794. [PMID: 31141181 PMCID: PMC6771503 DOI: 10.1002/elps.201900085] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Revised: 05/10/2019] [Accepted: 05/18/2019] [Indexed: 12/24/2022]
Abstract
In the past decade, more than 100 different cathinone derivatives slopped over entire Europe due to their enormous popularity. Generally, these novel psychoactive substances are easily available via the internet. This fact leads to various social problems, since cathinones are substances with consciousness-changing effects and are mainly misused for recreational matters by their consumers. Cathinones possess a chiral center including two enantiomeric forms with potentially different pharmacological behavior. This fact makes analytical method development regarding their chiral separation indispensable. In this study, a chiral capillary zone electrophoresis method for the enantioseparation of 61 cathinone and pyrovalerone derivatives was developed by means of four different β-cyclodextrin derivatives. As chiral selectors, native β-cyclodextrin as well as three of its derivatives namely acetyl-β-cyclodextrin, 2-hydroxypropyl-β-cyclodextrin, and carboxymethyl-β-cyclodextrin were used. The cathinone and pyrovalerone derivatives were either purchased in internet stores or seized by police. As a result, overall 58 of 61 studied substances were partially or baseline separated by at least one of the four chiral selectors using 10 mM of β-cyclodextrin derivative in a 10 mM sodium phosphate buffer (pH 2.5). Furthermore, the method was found to be suitable for simultaneous enantioseparations, for enantiomeric purity checks and to differentiate between positional isomers. Moreover, an intra- and an interday validation was performed successfully for each chiral selector to prove the robustness of the method.
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Affiliation(s)
- Johannes S. Hägele
- Department of Pharmaceutical ChemistryInstitute of Pharmaceutical SciencesUniversity of GrazGrazAustria
| | - Eva‐Maria Hubner
- Department of Pharmaceutical ChemistryInstitute of Pharmaceutical SciencesUniversity of GrazGrazAustria
| | - Martin G. Schmid
- Department of Pharmaceutical ChemistryInstitute of Pharmaceutical SciencesUniversity of GrazGrazAustria
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25
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Dong GL, Fang WH, Zhang L, Zhang J. In situ generated pyroglutamate bridged polyoxotitaniums with strong circular dichroism signal. CHINESE CHEM LETT 2019. [DOI: 10.1016/j.cclet.2019.01.032] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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26
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Meetani MA, Alremeithi RH, Mousa MK. Enantioseparation of Synthetic Cathinones Enantiomers with Tertiary Amine Structure in Urine and Plasma. J Chromatogr Sci 2019; 57:361-368. [DOI: 10.1093/chromsci/bmz008] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2018] [Revised: 12/23/2018] [Accepted: 01/09/2019] [Indexed: 01/31/2023]
Affiliation(s)
- Mohammed A Meetani
- Chemistry Department, College of science, United Arab Emirates University, Al-Ain, UAE
| | - Rashed H Alremeithi
- Chemistry Department, College of science, United Arab Emirates University, Al-Ain, UAE
| | - Muath K Mousa
- Chemistry Department, College of science, United Arab Emirates University, Al-Ain, UAE
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27
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Hägele JS, Schmid MG. Enantiomeric separation of Novel Psychoactive Substances by capillary electrophoresis using (+)-18-crown-6-tetracarboxylic acid as chiral selector. Chirality 2018; 30:1019-1026. [PMID: 29920777 DOI: 10.1002/chir.22981] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 03/20/2018] [Accepted: 04/23/2018] [Indexed: 01/21/2023]
Abstract
In the recent years, hundreds of Novel Psychoactive Substances (NPS) have entered both the European and the global drug market. These drugs, which are mainly used for recreational matters, have caused serious social problems. Every year, the spectrum of these misused drugs is enlarged by new derivatives, which are produced by modifications of basic structures of already well-known substances. Additionally, a lot of them possess a stereogenic center which leads to 2 enantiomeric forms. The fact that the pharmacological effects and potencies of the enantiomers of these chiral NPS may differ can be assumed from a broad spectrum of active pharmaceutical ingredients. For this reason, analytical method development regarding enantiomeric separation for these classes of substances is of great pharmaceutical and medical interest. The aim of this work was to create an easy-to-prepare chiral capillary electrophoresis method for the enantioseparation of NPS which contains a primary amino group by means of (+)-18-crown-6-tetracarboxylic acid as chiral selector. Novel Psychoactive Substances were purchased at various Internet stores or represent samples seized by Austrian police. The effects of selector concentration, the electrolyte composition, and the addition of organic modifiers to the background electrolyte on enantioseparation were investigated. Under optimized conditions, the use of 20-mM (+)-18-crown-6-tetracarboxylic acid, 10-mM Tris, and 30-mM citric acid buffer at pH 2.10 turned out to be effective. Fifteen of 24 tested NPS were resolved in their enantiomers within 15 minutes. It was found that all NPS were traded as racemic mixtures.
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Affiliation(s)
- Johannes S Hägele
- Department of Pharmaceutical Chemistry, Institute of Pharmaceutical Sciences, University of Graz, Graz, Austria
| | - Martin G Schmid
- Department of Pharmaceutical Chemistry, Institute of Pharmaceutical Sciences, University of Graz, Graz, Austria
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28
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Kadkhodaei K, Forcher L, Schmid MG. Separation of enantiomers of new psychoactive substances by high-performance liquid chromatography. J Sep Sci 2018; 41:1274-1286. [DOI: 10.1002/jssc.201701239] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Revised: 12/06/2017] [Accepted: 12/08/2017] [Indexed: 12/29/2022]
Affiliation(s)
- Kian Kadkhodaei
- Department of Pharmaceutical Chemistry, Institute of Pharmaceutical Sciences; University of Graz; Graz Austria
| | - Lisa Forcher
- Department of Pharmaceutical Chemistry, Institute of Pharmaceutical Sciences; University of Graz; Graz Austria
| | - Martin G. Schmid
- Department of Pharmaceutical Chemistry, Institute of Pharmaceutical Sciences; University of Graz; Graz Austria
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29
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Couto RAS, Gonçalves LM, Carvalho F, Rodrigues JA, Rodrigues CMP, Quinaz MB. The Analytical Challenge in the Determination of Cathinones, Key-Players in the Worldwide Phenomenon of Novel Psychoactive Substances. Crit Rev Anal Chem 2018; 48:372-390. [DOI: 10.1080/10408347.2018.1439724] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Rosa A. S. Couto
- LAQV/REQUIMTE, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Porto, Portugal
| | - Luís Moreira Gonçalves
- LAQV/REQUIMTE, Department of Chemistry and Biochemistry, Faculty of Sciences, University of Porto, Porto, Portugal
- Departamento de Química Fundamental, Instituto de Química, Universidade de São Paulo (USP), São Paulo, Brazil
| | - Félix Carvalho
- UCIBIO/REQUIMTE, Laboratory of Toxicology, Faculty of Pharmacy, University of Porto, Porto, Portugal
| | - José A. Rodrigues
- LAQV/REQUIMTE, Department of Chemistry and Biochemistry, Faculty of Sciences, University of Porto, Porto, Portugal
| | - Cecília M. P. Rodrigues
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Lisbon, Portugal
| | - M. Beatriz Quinaz
- LAQV/REQUIMTE, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Porto, Portugal
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Alremeithi R, Meetani MA, Alaidaros AA, Lanjawi A, Alsumaiti K. Simultaneous Quantitative Determination of Synthetic Cathinone Enantiomers in Urine and Plasma Using GC-NCI-MS. JOURNAL OF ANALYTICAL METHODS IN CHEMISTRY 2018; 2018:4396043. [PMID: 29805834 PMCID: PMC5902049 DOI: 10.1155/2018/4396043] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Revised: 02/06/2018] [Accepted: 02/25/2018] [Indexed: 05/17/2023]
Abstract
Development and validation of sensitive and selective method for enantioseparation and quantitation of synthetic cathinones is reported using GC-MS triple quadrupole mass spectrometry with negative chemical ionization (NCI) mode. Indirect chiral separation of thirty-six synthetic cathinone compounds has been achieved by using an optically pure chiral derivatizing agent (CDA) called (S)-(-)-N-(trifluoroacetyl)pyrrolidine-2-carbonyl chloride (L-TPC), which converts cathinone enantiomers into diastereoisomers that can be separated on achiral columns. As a result of using Ultra Inert 60 m column and performing slow heating rate (2°C/min) on the GC oven, an observed enhancement in enantiomer peak resolution has been achieved. An internal standard, (+)-cathinone, was used for quantitation of synthetic cathinones. Method validation in terms of linearities and sensitivity in terms of limits of detection (LODs), limits of quantitation (LOQs), recoveries, and reproducibilities has been obtained for fourteen selected compounds that examined simultaneously as a mixture after being spiked in urine and plasma. It was found that the LOD of the fourteen synthetic cathinones in urine was in the range of 0.26-0.76 µg/L, and in plasma, it was in the range of 0.26-0.34 µg/L. While the LOQ of the mixture in urine was in the range of 0.86-2.34 µg/L, and in plasma, it was in the range of 0.89-1.12 µg/L. Unlike the electron impact (EI) ion source, NCI showed better sensitivity by two orders of magnitude by comparing the obtained results with the recently published reports for quantitative analysis and enantioseparation of synthetic cathinones.
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Affiliation(s)
- Rashed Alremeithi
- Chemistry Department, United Arab Emirates University, P.O. Box 15551, Al-Ain, UAE
- General Department of Forensic Science and Criminology, Dubai Police, Dubai, UAE
| | - Mohammed A. Meetani
- Chemistry Department, United Arab Emirates University, P.O. Box 15551, Al-Ain, UAE
| | - Anas A. Alaidaros
- Chemistry Department, United Arab Emirates University, P.O. Box 15551, Al-Ain, UAE
| | - Adnan Lanjawi
- General Department of Forensic Science and Criminology, Dubai Police, Dubai, UAE
| | - Khalid Alsumaiti
- General Department of Forensic Science and Criminology, Dubai Police, Dubai, UAE
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31
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Silva B, Fernandes C, Guedes de Pinho P, Remião F. Chiral Resolution and Enantioselectivity of Synthetic Cathinones: A Brief Review. J Anal Toxicol 2017; 42:17-24. [DOI: 10.1093/jat/bkx074] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Accepted: 08/15/2017] [Indexed: 01/21/2023] Open
Affiliation(s)
- Bárbara Silva
- UCIBIO-REQUIMTE, Laboratório de Toxicologia, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto, Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal
- Laboratório de Química Orgânica e Farmacêutica, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal
| | - Carla Fernandes
- Laboratório de Química Orgânica e Farmacêutica, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal
- Centro Interdisciplinar de Investigação Marinha e Ambiental (CIIMAR), Edifício do Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, 4050-208 Matosinhos, Portugal
| | - Paula Guedes de Pinho
- UCIBIO-REQUIMTE, Laboratório de Toxicologia, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto, Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal
| | - Fernando Remião
- UCIBIO-REQUIMTE, Laboratório de Toxicologia, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto, Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal
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32
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Weiß JA, Kadkhodaei K, Schmid MG. Indirect chiral separation of 8 novel amphetamine derivatives as potential new psychoactive compounds by GC–MS and HPLC. Sci Justice 2017; 57:6-12. [DOI: 10.1016/j.scijus.2016.08.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Revised: 08/22/2016] [Accepted: 08/28/2016] [Indexed: 10/21/2022]
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33
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Development of an enantioseparation method for novel psychoactive drugs by HPLC using a Lux ® Cellulose-2 column in polar organic phase mode. Forensic Sci Int 2017; 270:232-240. [DOI: 10.1016/j.forsciint.2016.10.011] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Revised: 10/08/2016] [Accepted: 10/12/2016] [Indexed: 11/23/2022]
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34
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35
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Geryk R, Kalíková K, Schmid MG, Tesařová E. Enantioselective separation of biologically active basic compounds in ultra-performance supercritical fluid chromatography. Anal Chim Acta 2016; 932:98-105. [DOI: 10.1016/j.aca.2016.04.044] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Revised: 04/19/2016] [Accepted: 04/23/2016] [Indexed: 10/21/2022]
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36
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Chiral enantioresolution of cathinone derivatives present in "legal highs", and enantioselectivity evaluation on cytotoxicity of 3,4-methylenedioxypyrovalerone (MDPV). Forensic Toxicol 2016; 34:372-385. [PMID: 27594923 PMCID: PMC4988346 DOI: 10.1007/s11419-016-0324-y] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Accepted: 05/19/2016] [Indexed: 12/31/2022]
Abstract
Recently, great interest has been focused on synthetic cathinones since their consumption has increased exponentially. All synthetic cathinones exist as chiral molecules; the biological and/or toxicological properties of cathinones generally differ according to the enantiomers in human body. In this study, a chiral liquid chromatography method was developed to separate and determine the enantiomeric ratio of synthetic cathinones present in "legal highs" acquired in old smart shops or over the Internet. All the synthetic cathinones were efficiently enantio-separated with α and Rs ranging from 1.24 to 3.62 and from 1.24 to 10.52, respectively, using polysaccharide-based chiral stationary phases. All synthetic cathinones, with the exception of 4-methylethcathinone (4-MEC), were present in the commercialized "legal highs" in an enantiomeric proportion of 50:50. One of the studied chiral compounds was 3,4-methylenedioxypyrovalerone (MDPV), one of the most consumed cathinone derivative worldwide. Our research group has recently reported its hepatotoxicity in the racemic form. Thus, the analytical enantioresolution of the MDPV was scaled up to multi-milligram using a semi-preparative amylose tris-3,5-dimethylphenylcarbamate column (20 cm × 7.0 mm ID, 7 µm particle size). Both enantiomers were isolated with high enantiomeric purity (enantiomeric excess > 99 %). The toxicity of S-(-)-MDPV and R-(+)-MDPV was evaluated, for the first time, using primary cultures of rat hepatocytes. It was also possible to verify that MDPV enantiomers showed hepatotoxicity in a concentration-dependent manner, but displayed no enantioselective toxicity in this cell culture model.
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Abstract
This critical review presents the various synthetic approaches and chiral chemistry of metal-camphorate frameworks (MCamFs), which are homochiral metal-organic frameworks (MOFs) constructed from a camphorate ligand. The interest in this unique subset of homochiral MOFs is derived from the many interesting chiral features for both materials and life sciences, such as asymmetrical synthesis or crystallization, homochiral structural design, chiral induction, absolute helical control and ligand handedness. Additionally, we discuss the potential applications of homochiral MCamFs. This review will be of interest to researchers attempting to design other homochiral MOFs and those engaged in the extension of MOFs for applications such as chiral recognition, enantiomer separation, asymmetric catalysis, nonlinear sensors and devices.
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Affiliation(s)
- Zhi-Gang Gu
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, China.
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Albals D, Heyden YV, Schmid MG, Chankvetadze B, Mangelings D. Chiral separations of cathinone and amphetamine-derivatives: Comparative study between capillary electrochromatography, supercritical fluid chromatography and three liquid chromatographic modes. J Pharm Biomed Anal 2016; 121:232-243. [DOI: 10.1016/j.jpba.2015.12.007] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Accepted: 12/09/2015] [Indexed: 10/22/2022]
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39
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Tong S, Zhang H, Yan J. Analytical Enantioseparation of β-Substituted-2-Phenylpropionic Acids by High-Performance Liquid Chromatography with Hydroxypropyl-β-Cyclodextrin as Chiral Mobile Phase Additive. J Chromatogr Sci 2016; 54:593-7. [PMID: 26755500 DOI: 10.1093/chromsci/bmv192] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2015] [Accepted: 12/01/2015] [Indexed: 11/14/2022]
Abstract
Analytical enantioseparation of five β-substituted-2-phenylpropionic acids by high-performance liquid chromatography with hydroxypropyl-β-cyclodextrin (HP-β-CD) as chiral mobile phase additive was established in this paper, and chromatographic retention mechanism was studied. The effects of various factors such as the organic modifier, different ODS C18 columns and concentration of HP-β-CD were investigated. The chiral mobile phase was composed of methanol or acetonitrile and 0.5% triethylamine acetate buffer at pH 3.0 added with 25 mmol L(-1) of HP-β-CD, and baseline separations could be reached for all racemates. As for chromatographic retention mechanism, it was found that there was a negative correlation between the concentration of HP-β-CD in mobile phase and the retention factor under constant pH value and column temperature.
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Affiliation(s)
- Shengqiang Tong
- College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou 310032, China
| | - Hu Zhang
- College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou 310032, China
| | - Jizhong Yan
- College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou 310032, China
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Smith JP, Sutcliffe OB, Banks CE. An overview of recent developments in the analytical detection of new psychoactive substances (NPSs). Analyst 2016; 140:4932-48. [PMID: 26031385 DOI: 10.1039/c5an00797f] [Citation(s) in RCA: 102] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
New psychoactive substances (NPSs), sometimes referred to as "legal highs" in more colloquial environments/the media, are a class of compounds that have been recently made available for abuse (not necessarily recently discovered) which provide similar effects to the traditional well studied illegal drugs but are not always controlled under existing local, regional or international drug legislation. Following an unprecedented increase in the number of NPSs in the last 5 years (with 101 substances discovered for the first time in 2014 alone) its, occasionally fatal, consequences have been extensively reported in the media. Such NPSs are typically marketed as 'not for human consumption' and are instead labelled and sold as plant food, bath salts as well as a whole host of other equally nondescript aliases in order to bypass legislative controls. NPSs are a new multi-disciplinary research field with the main emphasis in terms of forensic identification due to their adverse health effects, which can range from minimal to life threatening and even fatalities. In this mini-review we overview this recent emerging research area of NPSs and the analytical approaches reported to provide detection strategies as well as detailing recent reports towards providing point-of-care/in-the-field NPS ("legal high") sensors.
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Affiliation(s)
- Jamie P Smith
- Faculty of Science and Engineering, School of Science and the Environment, Division of Chemistry and Environmental Science, Manchester Metropolitan University, Chester Street, Manchester M1 5GD, UK.
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41
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Enantioseparation of Citalopram by RP-HPLC, Using Sulfobutyl Ether-β-Cyclodextrin as a Chiral Mobile Phase Additive. Int J Anal Chem 2016; 2016:1231386. [PMID: 26880921 PMCID: PMC4736382 DOI: 10.1155/2016/1231386] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Accepted: 12/15/2015] [Indexed: 12/02/2022] Open
Abstract
Enantiomeric separation of citalopram (CIT) was developed using a reversed phase HPLC (RP-HPLC) with sulfobutylether-β-cyclodextrin (SBE-β-CD) as a chiral mobile phase additive. The effects of the pH value of aqueous buffer, concentration of chiral additive, composition of mobile phase, and column temperature on the enantioseparation of CIT were investigated on the Hedera ODS-2 C18 column (250 mm × 4.6 mm × 5.0 um). A satisfactory resolution was achieved at 25°C using a mobile phase consisting of a mixture of aqueous buffer (pH of 2.5, 5 mM sodium dihydrogen phosphate, and 12 mM SBE-β-CD), methanol, and acetonitrile with a volumetric ratio of 21 : 3 : 1 and flow rate of 1.0 mL/min. This analytical method was evaluated by examining the precision (lower than 3.0%), linearity (regression coefficients close to 1), limit of detection (0.070 µg/mL for (R)-CIT and 0.076 µg/mL for (S)-CIT), and limit of quantitation (0.235 µg/mL for (R)-CIT and 0.254 µg/mL for (S)-CIT).
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Regioisomeric and enantiomeric analyses of 24 designer cathinones and phenethylamines using ultra high performance liquid chromatography and capillary electrophoresis with added cyclodextrins. Forensic Sci Int 2015; 254:148-57. [DOI: 10.1016/j.forsciint.2015.06.026] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Revised: 06/15/2015] [Accepted: 06/29/2015] [Indexed: 11/22/2022]
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Analysis of a new drug of abuse: Cathinone derivative 1-(3,4-dimethoxyphenyl)-2-(ethylamino)pentan-1-one. J Sep Sci 2015; 38:825-8. [DOI: 10.1002/jssc.201401052] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Revised: 11/13/2014] [Accepted: 12/12/2014] [Indexed: 11/07/2022]
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Zhou MJ, Bouazzaoui S, Jones LE, Goodrich P, Bell SEJ, Sheldrake GN, Horton PN, Coles SJ, Fletcher NC. Isolation and structural determination of non-racemic tertiary cathinone derivatives. Org Biomol Chem 2015; 13:9629-36. [DOI: 10.1039/c5ob01306b] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this paper the dynamic resolution of racemic tertiary cathinones is demonstrated through co-crystallization with enantiopure aromatic tartaric acids.
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Affiliation(s)
- M.-J. Zhou
- School of Chemistry and Chemical Engineering
- Queen's University Belfast
- Belfast
- UK
| | - S. Bouazzaoui
- School of Chemistry and Chemical Engineering
- Queen's University Belfast
- Belfast
- UK
| | - L. E. Jones
- School of Chemistry and Chemical Engineering
- Queen's University Belfast
- Belfast
- UK
| | - P. Goodrich
- School of Chemistry and Chemical Engineering
- Queen's University Belfast
- Belfast
- UK
| | - S. E. J. Bell
- School of Chemistry and Chemical Engineering
- Queen's University Belfast
- Belfast
- UK
| | - G. N. Sheldrake
- School of Chemistry and Chemical Engineering
- Queen's University Belfast
- Belfast
- UK
| | - P. N. Horton
- University of Southampton
- Chemistry Department
- EPSRC National Crystallography Service
- Southampton
- UK
| | - S. J. Coles
- University of Southampton
- Chemistry Department
- EPSRC National Crystallography Service
- Southampton
- UK
| | - N. C. Fletcher
- School of Chemistry and Chemical Engineering
- Queen's University Belfast
- Belfast
- UK
- Department of Chemistry
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Wang CC, Hartmann-Fischbach P, Krueger TR, Lester A, Simonson A, Wells TL, Wolk MO, Hidlay NJ. Fast and Sensitive Chiral Analysis of Amphetamines and Cathinones in Equine Urine and Plasma Using Liquid Chromatography Tandem Mass Spectrometry. ACTA ACUST UNITED AC 2015. [DOI: 10.4236/ajac.2015.613094] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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46
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Taschwer M, Weiß JA, Kunert O, Schmid MG. Analysis and characterization of the novel psychoactive drug 4-chloromethcathinone (clephedrone). Forensic Sci Int 2014; 244:e56-9. [PMID: 25280452 DOI: 10.1016/j.forsciint.2014.09.007] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2014] [Revised: 09/01/2014] [Accepted: 09/14/2014] [Indexed: 11/19/2022]
Abstract
Novel psychoactive drugs, such as amphetamine-, cathinone-, benzofury- and tryptamine derivatives, gained high popularity on the global drug market in the last years. These drugs are sold via the Internet as for example "research chemicals", "room odorizers" or "lawn fertilizers" by different online suppliers. They are also known as "Legal Highs", among them, cathinone derivatives play an important role. Well known substituted cathinone derivatives are mephedrone, brephedrone and flephedrone. Since a couple of weeks, a chlorine substituted methcathinone derivative, namely clephedrone (4-chloromethcathinone), is commercially available via the Internet from www.deboralabs.com. The goal of this study was to confirm identity of this substance, which was done successfully by GC-MS and NMR. Since all cathinone derivatives are chiral, it was found out, whether the purchased sample was present as a racemic mixture. For this purpose, methods for enantioseparation by GC and CE were developed and applied successfully. In case of CE a chiral selector was added, whereas chiral separation with GC-MS was done indirectly, after derivatization of clephedrone with trifluoroacetyl-l-prolyl chloride.
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Affiliation(s)
- Magdalena Taschwer
- Department of Pharmaceutical Chemistry, Institute of Pharmaceutical Sciences, Karl-Franzens-University Graz, Universitätsplatz 1, A-8010 Graz, Austria
| | - Jennifer A Weiß
- Department of Pharmaceutical Chemistry, Institute of Pharmaceutical Sciences, Karl-Franzens-University Graz, Universitätsplatz 1, A-8010 Graz, Austria
| | - Olaf Kunert
- Department of Pharmaceutical Chemistry, Institute of Pharmaceutical Sciences, Karl-Franzens-University Graz, Universitätsplatz 1, A-8010 Graz, Austria
| | - Martin G Schmid
- Department of Pharmaceutical Chemistry, Institute of Pharmaceutical Sciences, Karl-Franzens-University Graz, Universitätsplatz 1, A-8010 Graz, Austria.
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