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Lv Q, Wu Y, Chen L, Dai J. "Ghost peaks" in reversed-phase liquid chromatography separation of an electron-rich aniline compound: Mechanism and solution for this phenomenon. J Chromatogr A 2023; 1707:464274. [PMID: 37586301 DOI: 10.1016/j.chroma.2023.464274] [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: 06/06/2023] [Revised: 08/01/2023] [Accepted: 08/01/2023] [Indexed: 08/18/2023]
Abstract
Two "ghost peaks" appeared in the process of developing an impurities analytical method for an electron-rich aniline compound by RP-HPLC. Surprisingly, the "ghost peaks" disappeared when the mobile phase was re-prepared. The "ghost peak" slowly began to reappear and gradually increased after increasing the injection volume or changing different instruments and columns. In this paper, the structures of two "ghost peaks" were analyzed by LC-MS/MS, which were identified as the dimer of the main peak and the oxidation products of the dimer. The mechanism was confirmed by studying the "ghost peaks" appearance phenomenon in the mobile phase with different pH values, different types of buffer salts, and different brand chromatographic columns. The potential chemical behavior of this type of compound on the column was clearly revealed in the process of RP-HPLC separation. The coupling reaction of electron-rich aniline compounds can be induced by partial or complete dissociation of the silanol group to Si-O-in the stationary phase of a reversed-phase chromatographic column under neutral and basic conditions of the mobile phase. Adding inorganic salts to the mobile phase can inhibit the reaction, and the higher salt concentration, the stronger the effect.
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Affiliation(s)
- Qinghui Lv
- Analytical Research Department, Chengdu Hyperway Pharmaceutical Co., Ltd., No. 802, 8th Floor, Building 7, No. 88, Keyuan South Road, Hi-tech Zone, Chengdu, Sichuan Province, PR China
| | - Yue Wu
- School of Pharmacy, Chengdu Medical College, No.783, Xindu Avenue, Xindu District, Chengdu, Sichuan Province, PR China
| | - Lili Chen
- Analytical Research Department, Chengdu Hyperway Pharmaceutical Co., Ltd., No. 802, 8th Floor, Building 7, No. 88, Keyuan South Road, Hi-tech Zone, Chengdu, Sichuan Province, PR China.
| | - Jing Dai
- School of Pharmacy, Chengdu Medical College, No.783, Xindu Avenue, Xindu District, Chengdu, Sichuan Province, PR China.
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2
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Zheng L, Wang L, Li D, Xie C, Gao Z, Lin J, Ye J, Chen W, Li M. Investigation of nirmatrelvir epimerization occurred in analytical sample solution by using high resolution LC-MS n, NMR, and hydrogen/deuterium exchange study. J Pharm Biomed Anal 2023; 227:115284. [PMID: 36804289 DOI: 10.1016/j.jpba.2023.115284] [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: 12/16/2022] [Revised: 02/07/2023] [Accepted: 02/08/2023] [Indexed: 02/13/2023]
Abstract
During the related substances testing of nirmatrelvir, an unknown peak was observed and the level of the peak increased over time during the storage of the sample solution. By using a strategy including LC-PDA/UV-MSn analysis, the degradant was rapidly identified as an epimer of nirmatrelvir, a solution degradation product that is caused by the trace amount of alkaline impurities leaching from the glass HPLC vials. In addition, by using hydrogen/deuterium exchange NMR spectroscopy analysis, the epimerization position was determined to be the carbon α to the adjacent cyano group. Further investigation indicated that the occurrence of the solution degradation can be suppressed when the glass HPLC vials were replaced by plastic HPLC or mass spectrometric grade vials.
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Affiliation(s)
- Lewei Zheng
- Center of Excellence for Modern Analytical Technologies (CEMAT) Huahai Pharmaceutical Co., Ltd, Xunqiao, Linhai, Zhejiang 317024, PR China
| | - Lingqiao Wang
- Center of Excellence for Modern Analytical Technologies (CEMAT) Huahai Pharmaceutical Co., Ltd, Xunqiao, Linhai, Zhejiang 317024, PR China
| | - Dan Li
- Center of Excellence for Modern Analytical Technologies (CEMAT) Huahai Pharmaceutical Co., Ltd, Xunqiao, Linhai, Zhejiang 317024, PR China
| | - Chongjun Xie
- Center of Excellence for Modern Analytical Technologies (CEMAT) Huahai Pharmaceutical Co., Ltd, Xunqiao, Linhai, Zhejiang 317024, PR China
| | - Zhiyuan Gao
- Center of Excellence for Modern Analytical Technologies (CEMAT) Huahai Pharmaceutical Co., Ltd, Xunqiao, Linhai, Zhejiang 317024, PR China
| | - Jinsheng Lin
- Center of Excellence for Modern Analytical Technologies (CEMAT) Huahai Pharmaceutical Co., Ltd, Xunqiao, Linhai, Zhejiang 317024, PR China
| | - Jian Ye
- Center of Excellence for Modern Analytical Technologies (CEMAT) Huahai Pharmaceutical Co., Ltd, Xunqiao, Linhai, Zhejiang 317024, PR China
| | - Wenbin Chen
- Center of Excellence for Modern Analytical Technologies (CEMAT) Huahai Pharmaceutical Co., Ltd, Xunqiao, Linhai, Zhejiang 317024, PR China
| | - Min Li
- Center of Excellence for Modern Analytical Technologies (CEMAT) Huahai Pharmaceutical Co., Ltd, Xunqiao, Linhai, Zhejiang 317024, PR China; Huahai US, Inc. 700 Atrium Drive, Somerset, NJ 08873, USA.
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3
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Zhong X, Lv Q, Yong Q, Hu W, Li D, Ji S, Zhan L, Chen W, Li M, Lin J, Sun C. Forced degradation studies of elagolix sodium with the implementation of high resolution LC-UV-PDA-MS n (n = 1,2,3…) and NMR structural elucidation. J Pharm Biomed Anal 2023; 224:115198. [PMID: 36495708 DOI: 10.1016/j.jpba.2022.115198] [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: 10/10/2022] [Revised: 11/23/2022] [Accepted: 12/04/2022] [Indexed: 12/12/2022]
Abstract
Elagolix sodium (ELS) is a marketed product using to release moderate to severe endometriosis-associated pain. It contains functional groups such as carboxyl group, secondary amino group, 2,4-dioxo pyrimidinyl and several benzyl or benzyl-like position hydrogen atom that are susceptive to occur stress degradation. Forced degradation studies of ELS reveal different degradation profiles of the drug substance which are conducted under photo, thermal, acidic, neutral, alkaline and hydrogen peroxide oxidative conditions in the direction of the ICH guidances. With structural elucidation of LC-PDA/UV-MSn and NMR, the degradants were identified, and seven new degradants are reported in this study. It is confirmed that most of the degradation behaviors of ELS are related to the carboxyl group and secondary amino group in the 3-carboxyl propylamine side chain. Under the oxidative condition using hydrogen peroxide as the oxidant, the secondary amine was oxidized to form an N-hydrogen amine degradant and two further degradants of amine and carbonyl analogs were generated. Under the alkaline degradation condition, the ELS is proven to be stable and no obvious degradants are produced. On the other hand, under the acidic and neutral degradation condition, the 2,4-dioxo pyrimidinyl core of elagolix sodium is stable but the carboxyl group and secondary amine will occur ring cyclization to form the δ-lactam analogs of elagolix sodium. The plausible mechanisms for the degradation of acidic, thermal, photo-degradative and hydrogen peroxide mediated oxidative of elagolix sodium are proposed. It is worth to note that DP-3-4 are the potential degradants which are only found in the solution degradation and are not the real impurities of elagolix sodium.
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Affiliation(s)
- Xueni Zhong
- College of Pharmaceutical Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang 310058, PR China
| | - Qianqian Lv
- Center of Excellence for Modern Analytical Technologies (CEMAT), Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang 317204, PR China
| | - Qiyun Yong
- Center of Excellence for Modern Analytical Technologies (CEMAT), Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang 317204, PR China
| | - Wenping Hu
- Center of Excellence for Modern Analytical Technologies (CEMAT), Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang 317204, PR China
| | - Dan Li
- College of Pharmaceutical Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang 310058, PR China
| | - Shuhui Ji
- College of Pharmaceutical Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang 310058, PR China
| | - Liuyue Zhan
- College of Pharmaceutical Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang 310058, PR China
| | - Wenbin Chen
- College of Pharmaceutical Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang 310058, PR China
| | - Min Li
- Center of Excellence for Modern Analytical Technologies (CEMAT), Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang 317204, PR China
| | - Jinsheng Lin
- College of Pharmaceutical Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang 310058, PR China; Center of Excellence for Modern Analytical Technologies (CEMAT), Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang 317204, PR China.
| | - Cuirong Sun
- College of Pharmaceutical Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang 310058, PR China.
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4
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Horne S, Vera MD, Nagavelli LR, Sayeed VA, Heckman L, Johnson D, Berger D, Yip YY, Krahn CL, Sizukusa LO, Rocha NFM, Bream RN, Ludwig J, Keire DA, Condran G. Regulatory Experiences with Root Causes and Risk Factors for Nitrosamine Impurities in Pharmaceuticals. J Pharm Sci 2023; 112:1166-1182. [PMID: 36599405 DOI: 10.1016/j.xphs.2022.12.022] [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: 11/01/2022] [Revised: 12/19/2022] [Accepted: 12/23/2022] [Indexed: 01/02/2023]
Abstract
N-Nitrosamines (also referred to as nitrosamines) are a class of substances, many of which are highly potent mutagenic agents which have been classified as probable human carcinogens. Nitrosamine impurities have been a concern within the pharmaceutical industry and by regulatory authorities worldwide since June 2018, when regulators were informed of the presence of N-nitrosodimethylamine (NDMA) in the angiotensin-II receptor blocker (ARB) medicine, valsartan. Since that time, regulatory authorities have collaborated to share information and knowledge on issues related to nitrosamines with a goal of promoting convergence on technical issues and reducing and mitigating patient exposure to harmful nitrosamine impurities in human drug products. This paper shares current scientific information from a quality perspective on risk factors and potential root causes for nitrosamine impurities, as well as recommendations for risk mitigation and control strategies.
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Affiliation(s)
| | - Matthew D Vera
- US Food and Drug Administration (US FDA), Silver Spring, MD, 20993, USA
| | - Laxma R Nagavelli
- US Food and Drug Administration (US FDA), Silver Spring, MD, 20993, USA
| | - Vilayat A Sayeed
- US Food and Drug Administration (US FDA), Silver Spring, MD, 20993, USA
| | - Laurel Heckman
- US Food and Drug Administration (US FDA), Silver Spring, MD, 20993, USA
| | - Deborah Johnson
- US Food and Drug Administration (US FDA), Silver Spring, MD, 20993, USA
| | - Dan Berger
- US Food and Drug Administration (US FDA), Silver Spring, MD, 20993, USA
| | | | | | | | | | - Robert N Bream
- European Medicines Agency (EMA, EU), Amsterdam, the Netherlands
| | - Joachim Ludwig
- Bundesinstitut für Arzneimittel und Medizinprodukte (BfArM), Bonn, Germany
| | - David A Keire
- US Food and Drug Administration (US FDA), St Louis, MO, 63110, USA
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5
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Wang KC, Guo Q, Kuang Z, Jin J, Li D, Chen W, Zhu W, Li M. Structural elucidation of two novel degradants of lurasidone and their formation mechanisms under free radical-mediated oxidative and photolytic conditions via liquid chromatography-photodiode array/ultraviolet-tandem mass spectrometry and one-dimensional/two-dimensional nuclear magnetic resonance spectroscopy. JOURNAL OF MASS SPECTROMETRY : JMS 2022; 57:e4871. [PMID: 35739062 DOI: 10.1002/jms.4871] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 05/29/2022] [Accepted: 05/31/2022] [Indexed: 06/15/2023]
Abstract
Lurasidone is an antipsychotic drug clinically used for the treatment of schizophrenia and bipolar disorder. During a mechanism-based forced degradation study of lurasidone, two novel degradation products were observed under free radical-mediated oxidative (via AIBN) and solution photolytic conditions. The structures of the two novel degradants were identified through an approach combining HPLC, LC-MSn (n = 1, 2), preparative HPLC purification and NMR spectroscopy. The degradant formed under the free radical-mediated condition is an oxidative degradant with half of the piperazine ring cleaved to form two formamides; a mechanism is proposed for the formation of the novel N,N'-diformyl degradant, which should be readily applicable to other drugs that contain a piperazine moiety that is widely present in drug molecules. The degradant observed under the solution photolytic condition is identified as the photo-induced isomer of lurasidone with the benzisothiazole ring altered into a benzothiazole ring.
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Affiliation(s)
- Kathy Cheng Wang
- Center of Excellence for Modern Analytical Technologies (CEMAT), Huahai Pharmaceutical Co., Ltd., Linhai, Zhejiang, China
| | - Qiaohong Guo
- Center of Excellence for Modern Analytical Technologies (CEMAT), Huahai Pharmaceutical Co., Ltd., Linhai, Zhejiang, China
| | - Zijian Kuang
- Center of Excellence for Modern Analytical Technologies (CEMAT), Huahai Pharmaceutical Co., Ltd., Linhai, Zhejiang, China
| | - Jianyang Jin
- Center of Excellence for Modern Analytical Technologies (CEMAT), Huahai Pharmaceutical Co., Ltd., Linhai, Zhejiang, China
| | - Dan Li
- Center of Excellence for Modern Analytical Technologies (CEMAT), Huahai Pharmaceutical Co., Ltd., Linhai, Zhejiang, China
| | - Wenbin Chen
- Center of Excellence for Modern Analytical Technologies (CEMAT), Huahai Pharmaceutical Co., Ltd., Linhai, Zhejiang, China
| | - Wenquan Zhu
- Center of Excellence for Modern Analytical Technologies (CEMAT), Huahai Pharmaceutical Co., Ltd., Linhai, Zhejiang, China
- Quality Research Department of API, Zhejiang Huahai Pharmaceutical Co., Ltd., Linhai, Zhejiang, China
| | - Min Li
- Center of Excellence for Modern Analytical Technologies (CEMAT), Huahai Pharmaceutical Co., Ltd., Linhai, Zhejiang, China
- Huahai US, Inc., Somerset, New Jersey, USA
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6
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Huang M, Yao B, Jiang M, Sun F, You J, Huang F, Zhao Y, Wu S, He X, Song X. "Ghost peaks" of olmesartan medoxomil: Two solution degradation products of olmesartan medoxomil via oxidation mediated by metal ions. JOURNAL OF MASS SPECTROMETRY : JMS 2022; 57:e4821. [PMID: 35347807 DOI: 10.1002/jms.4821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 02/24/2022] [Accepted: 03/01/2022] [Indexed: 06/14/2023]
Abstract
Two unknown solution degradants were found during the dissolution testing in 0.1-M HCl for olmesartan medoxomil (OLM) tablets. The structure of the degradants was identified and characterized by liquid chromatography-ultraviolet (LC-UV), liquid chromatography with tandem mass spectrometry (LC-MS/MS), and nuclear magnetic resonance (NMR) and demonstrated to be cyclization of tetrazole and benzene in the olmesartan (OL) and OLM structures. A series of studies including stress studies, simulation studies, and mechanism-based studies were performed to reveal the potential mechanisms that lead to the formation of the unknown degradants. The study results demonstrated that the degradation was catalyzed with radicals that originated from the metal ions leached from the inner surface of high-performance liquid chromatography (HPLC) glass vials with dissolved oxygen under acidic condition. Prerinsing the glass vials with acidic solution dissolved with EDTA can effectively avoid the generation of such oxidative impurities. The present work provides new insights into the understanding of degradation pathways of OLM, which might support the development of OLM tablets.
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Affiliation(s)
- Minxia Huang
- Dongguan HEC Generic Drug R&D Co., Ltd., Dongguan, China
- State Key Laboratory of Anti-Infective Drug Development, Sunshine Lake Pharma Co., Ltd., Dongguan, China
| | - Beiyang Yao
- Dongguan HEC Generic Drug R&D Co., Ltd., Dongguan, China
- State Key Laboratory of Anti-Infective Drug Development, Sunshine Lake Pharma Co., Ltd., Dongguan, China
| | - Manhua Jiang
- Dongguan HEC Generic Drug R&D Co., Ltd., Dongguan, China
- State Key Laboratory of Anti-Infective Drug Development, Sunshine Lake Pharma Co., Ltd., Dongguan, China
| | - Fuzhou Sun
- Dongguan HEC Generic Drug R&D Co., Ltd., Dongguan, China
- State Key Laboratory of Anti-Infective Drug Development, Sunshine Lake Pharma Co., Ltd., Dongguan, China
| | - Jinsong You
- Dongguan HEC Generic Drug R&D Co., Ltd., Dongguan, China
- State Key Laboratory of Anti-Infective Drug Development, Sunshine Lake Pharma Co., Ltd., Dongguan, China
| | - Fangfang Huang
- Dongguan HEC Generic Drug R&D Co., Ltd., Dongguan, China
- State Key Laboratory of Anti-Infective Drug Development, Sunshine Lake Pharma Co., Ltd., Dongguan, China
| | - Yanping Zhao
- Dongguan HEC Generic Drug R&D Co., Ltd., Dongguan, China
- State Key Laboratory of Anti-Infective Drug Development, Sunshine Lake Pharma Co., Ltd., Dongguan, China
| | - Shuming Wu
- Dongguan HEC Generic Drug R&D Co., Ltd., Dongguan, China
- State Key Laboratory of Anti-Infective Drug Development, Sunshine Lake Pharma Co., Ltd., Dongguan, China
| | - Xinqian He
- Dongguan HEC Generic Drug R&D Co., Ltd., Dongguan, China
- Ruyuan HEC Pharmaceutical Glass Technology Co., Ltd., Shaoguan, China
| | - Xuezhi Song
- Dongguan HEC Generic Drug R&D Co., Ltd., Dongguan, China
- State Key Laboratory of Anti-Infective Drug Development, Sunshine Lake Pharma Co., Ltd., Dongguan, China
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Lin J, Chen F, Bao C, Ma J, Li D, Zheng L, Zhu W, Chen W, Liu X. Investigation of an artificial solution degradant of linagliptin: An undesired linagliptin urea derivative generates in sample preparation of linagliptin tablet treated by sonication in acetonitrile containing diluent. J Pharm Biomed Anal 2021; 210:114540. [PMID: 34954487 DOI: 10.1016/j.jpba.2021.114540] [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: 10/12/2021] [Revised: 12/17/2021] [Accepted: 12/17/2021] [Indexed: 11/25/2022]
Abstract
During the related substances testing method development for linagliptin tablet, an unknown peak was observed in HPLC chromatograms with a level exceeding the identification threshold. By using a strategy that combines LC-PDA/UV-MSn with mechanism-based stress studies, the unknown peak was rapidly identified as linagliptin urea, a solution degradant that is caused by the reaction between the API and hydrocyanic acid with sonication treatment to accelerate dissolution of the drug substance in sample preparation of linagliptin tablets, and hydrocyanic acid is a known impurity in HPLC grade acetonitrile and acetonitrile is used as part of diluent. The mechanism of the solution degradation chemistry was verified by stressing linagliptin API with trimethylsilyl cyanide (TMSCN, which can give off HCN slowly in the presence of water) treated with sonication in the sample preparation. Further investigation found that when the sonication treatment was replaced by vortex vibration in the process of the sample preparation, the RRT 1.28 species was decreased to below the level of the detection limit (0.02%). The structure of this impurity was further confirmed through the synthesis of the impurity and subsequent structure characterization by 1D and 2D NMR. Due to the presence of trace amount of HCN in HPLC grade acetonitrile, these types of solution degradation would likely occur in analysis of pharmaceutical finished products containing APIs with primary and secondary amine moieties drug product during sample preparations, particularly when sonication treatment is used to accelerate dissolution of drug substance from the finished drug product. In the GMP quality control laboratories, such events may trigger undesirable out-of-specification (OOS) events. Hence, the results of this paper can help to prevent these events from happening in the first place or resolve these OOS events in GMP laboratories.
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Affiliation(s)
- Jinsheng Lin
- Center of Excellence for Modern Analytical Technologies (CEMAT), Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang 317204, PR China; College of Pharmaceutical Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang 310058, PR China.
| | - Feifei Chen
- Center of Excellence for Modern Analytical Technologies (CEMAT), Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang 317204, PR China
| | - Chaohua Bao
- Quality Control Department of Formulation Project Management, Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang 317204, PR China
| | - Jian Ma
- Center of Excellence for Modern Analytical Technologies (CEMAT), Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang 317204, PR China
| | - Dan Li
- Center of Excellence for Modern Analytical Technologies (CEMAT), Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang 317204, PR China
| | - Lewei Zheng
- Center of Excellence for Modern Analytical Technologies (CEMAT), Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang 317204, PR China
| | - Wenquan Zhu
- Center of Excellence for Modern Analytical Technologies (CEMAT), Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang 317204, PR China
| | - Wenbin Chen
- Center of Excellence for Modern Analytical Technologies (CEMAT), Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang 317204, PR China
| | - Xiaoming Liu
- Formulation Plant, Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang 317204, PR China
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Hao G, Wang H, Lai X, Sun F, You J, Huang F, Liu Y, Huang L, Xin L, Song X, He X. Azithromycin "ghost peak": A solution degradation product of azithromycin via leaching from borosilicate glass volumetric flasks and vials. J Pharm Biomed Anal 2021; 204:114248. [PMID: 34274596 DOI: 10.1016/j.jpba.2021.114248] [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: 04/08/2021] [Revised: 06/30/2021] [Accepted: 07/01/2021] [Indexed: 11/25/2022]
Abstract
An interference peak was found while detecting related substances of azithromycin. It is impressive that the degradation peak occurred at about 70 min in the next injection of the test solution (4 mg/mL or higher). Once the degradation peak was observed, it would keep growing. By using a strategy that Q-TOF high resolution mass spectrometry with mechanism-based stress studies, followed by preparative subsequent structure characterization by 1D and 2D NMR, the unknown peak was identified as azithromycin hydrogen borate. It apparently results from azithromycin and residual boron leaching out of the inner surface of the glass volumetric flasks and vials used in the sample preparation. By simulating the above chemical process, boric acid and azithromycin were dissolved in the same extraction diluent and a big interference peak occurred. It was found that boron-free flasks and vials, such as PMP or PP flasks and PTFE or PP vials could be used for the detection of azithromycin related substances to avoid the production of azithromycin hydrogen borate.
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Affiliation(s)
- Gugu Hao
- Dongguan HEC Generic Drug R&D Co., Ltd, Dongguan, 523871, China; State Key Laboratory of Anti-Infective Drug Development, Sunshine Lake Pharma Co., Ltd., Dongguan 523871, China
| | - Hai Wang
- Dongguan HEC Generic Drug R&D Co., Ltd, Dongguan, 523871, China; State Key Laboratory of Anti-Infective Drug Development, Sunshine Lake Pharma Co., Ltd., Dongguan 523871, China
| | - Xiaoyan Lai
- Dongguan HEC Generic Drug R&D Co., Ltd, Dongguan, 523871, China; State Key Laboratory of Anti-Infective Drug Development, Sunshine Lake Pharma Co., Ltd., Dongguan 523871, China
| | - Fuzhou Sun
- Dongguan HEC Generic Drug R&D Co., Ltd, Dongguan, 523871, China; State Key Laboratory of Anti-Infective Drug Development, Sunshine Lake Pharma Co., Ltd., Dongguan 523871, China
| | - Jinsong You
- Dongguan HEC Generic Drug R&D Co., Ltd, Dongguan, 523871, China; State Key Laboratory of Anti-Infective Drug Development, Sunshine Lake Pharma Co., Ltd., Dongguan 523871, China
| | - Fangfang Huang
- Dongguan HEC Generic Drug R&D Co., Ltd, Dongguan, 523871, China; State Key Laboratory of Anti-Infective Drug Development, Sunshine Lake Pharma Co., Ltd., Dongguan 523871, China
| | - Yuting Liu
- Dongguan HEC Generic Drug R&D Co., Ltd, Dongguan, 523871, China; State Key Laboratory of Anti-Infective Drug Development, Sunshine Lake Pharma Co., Ltd., Dongguan 523871, China
| | - Liang Huang
- Dongguan HEC Generic Drug R&D Co., Ltd, Dongguan, 523871, China; State Key Laboratory of Anti-Infective Drug Development, Sunshine Lake Pharma Co., Ltd., Dongguan 523871, China
| | - Libo Xin
- Dongguan HEC Generic Drug R&D Co., Ltd, Dongguan, 523871, China; State Key Laboratory of Anti-Infective Drug Development, Sunshine Lake Pharma Co., Ltd., Dongguan 523871, China
| | - Xuezhi Song
- Dongguan HEC Generic Drug R&D Co., Ltd, Dongguan, 523871, China; State Key Laboratory of Anti-Infective Drug Development, Sunshine Lake Pharma Co., Ltd., Dongguan 523871, China.
| | - Xinqian He
- Dongguan HEC Generic Drug R&D Co., Ltd, Dongguan, 523871, China; Ruyuan HEC Pharmaceutical Glass Technology, Shaoguan, 512700, China.
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9
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Wang S, Lin J, Li D, Huang T, Zhu W, Chen W, Li M, Shen W. Study of the isomeric Maillard degradants, glycosylamine and Amadori rearrangement products, and their differentiation via MS 2 fingerprinting from collision-induced decomposition of protonated ions. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2021; 35:e9062. [PMID: 33533047 DOI: 10.1002/rcm.9062] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Revised: 01/23/2021] [Accepted: 01/25/2021] [Indexed: 06/12/2023]
Abstract
RATIONALE The focus of this work was to study glycosylamine and Amadori rearrangement products (ARPs), the two major degradants in the Maillard reactions of pharmaceutical interest, and utilize their MS2 fingerprints by liquid chromatography/high-resolution tandem mass spectrometry (LC/HRMS2 ) to quickly distinguish the two isomeric degradants. These two types of degradants are frequently encountered in the compatibility and stability studies of drug products containing primary or secondary amine active pharmaceutical ingredients (APIs), which are formulated with excipients consisting of reducing sugar functionalities. METHODS Vortioxetine was employed as the primary model compound to react with lactose to obtain the glycosylamine and ARP degradants of the Maillard reaction, and their MS2 spectra (MS2 fingerprints) were obtained by LC/MS2 . Subsequently, the two degradants were isolated via preparative HPLC and their structures were confirmed by one- and two-dimensional (1D and 2D) nuclear magnetic resonance (NMR) determination. RESULTS The MS2 fingerprints of the two degradants display significantly different profiles, despite the fact that many common fragments are observed. Specifically, protonated glycosylamine shows a prominent characteristic fragment of [Mvort + C2 H3 O]+ at m/z 341 (Mvort is the vortioxetine core), while protonated ARP shows a prominent characteristic fragment of [Mvort + CH]+ at m/z 311. Further study of the Maillard reactions between several other structurally diverse primary/secondary amines and lactose produced similar patterns. CONCLUSIONS The study suggests that the characteristic MS2 fragment peaks and their ratios may be used to differentiate the glycosylamine and ARP degradants, the two isomeric degradants of the Maillard reaction, which are commonly encountered in finished dosage forms of pharmaceutical products containing primary and secondary amine APIs.
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Affiliation(s)
- Shaolan Wang
- Center of Excellence for Modern Analytical Technologies (CEMAT), Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang, 317204, China
- Department of Pharmaceutical Analysis, China Pharmaceutical University, Nanjing, 210009, China
| | - Jinsheng Lin
- Center of Excellence for Modern Analytical Technologies (CEMAT), Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang, 317204, China
| | - Dan Li
- Center of Excellence for Modern Analytical Technologies (CEMAT), Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang, 317204, China
| | - Tianpei Huang
- Center of Excellence for Modern Analytical Technologies (CEMAT), Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang, 317204, China
| | - Wenquan Zhu
- Center of Excellence for Modern Analytical Technologies (CEMAT), Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang, 317204, China
| | - Wenbin Chen
- Center of Excellence for Modern Analytical Technologies (CEMAT), Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang, 317204, China
| | - Min Li
- Center of Excellence for Modern Analytical Technologies (CEMAT), Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang, 317204, China
- Huahai US, Inc., 700 Atrium Drive, Somerset, NJ, 08873, USA
| | - Weiyang Shen
- Department of Pharmaceutical Analysis, China Pharmaceutical University, Nanjing, 210009, China
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10
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Tarfiei MA, Tabrizi AB, Jouyban A. Trace Extraction of Metoprolol from Plasma, Urine and EBC Samples Using Modified Magnetic Nanoparticles Followed by Spectrofluorimetric Determination for Drug Monitoring Purposes. CURR PHARM ANAL 2020. [DOI: 10.2174/1573412915666190328212231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Background:
Metoprolol is a selective β1-adrenergic receptor antagonist (β-blockers). It is
widely used for the treatment of hypertension and other related diseases. Metoprolol can be used as a
doping agent in sports, thus has been included in the list of forbidden drugs. In Iran, therapeutic drug
monitoring (TDM) of β-blockers is an applied procedure in some cases. A therapeutic regimen could be
easily managed by the determination of drug levels in biological fluids which is a relatively costly process
and requires highly skilled technical staff. Using a simple and low-cost analytical procedure may
help to use TDM in routine clinical practice.
Methods:
A real biological sample was prepared and its pH was adjusted to 3-4, then metoprolol was
quickly extracted using magnetic iron oxide nanoparticles (MIONPs) modified by sodium dodecyl sulfate
(SDS) and determined by applying spectrofluorimetry at 340 ± 3 nm after excitation at 283 ± 3 nm.
Results:
The extraction and determination conditions including, the amount of MIONPs and SDS, pH of
the solution, standing time, desorption solvent type and volume were investigated and adjusted. Calibration
curves were linear over the concentration range of 6–100 ng/mL for plasma and 5–100 ng/mL for
water, urine and exhaled breath condensate samples, respectively. Intra and inter-day precision values
for determination of metoprolol in different samples were less than 5.6 % and 6 %, respectively, and
accuracy (as a relative error) was better than 5 %. Moreover, standard addition recovery tests were carried
out, and the analytical recoveries ranged from 86 % to 113 %. The limits of detection (LOD) and
limits of quantification (LOQ) of metoprolol were found to be in the range of 2.1-3.4 ng/mL and 6.3-
10.2 ng/mL, respectively.
Conclusion:
The developed method was successfully applied to biological samples taken from a volunteer
who was given an oral tablet of 50 mg metoprolol.
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Affiliation(s)
- Mohammad Ali Tarfiei
- Pharmaceutical Analysis Research Center and Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz 51664, Iran
| | - Ahad Bavili Tabrizi
- Biotechnology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Abolghasem Jouyban
- Pharmaceutical Analysis Research Center and Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz 51664, Iran
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11
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Structure Elucidation and Mechanistic Study of a New Dimeric Degradant in Ropinirole Hydrochloride Extended-Release Tablets. Pharm Res 2020; 37:136. [DOI: 10.1007/s11095-020-02863-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Accepted: 06/23/2020] [Indexed: 11/28/2022]
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12
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Tian Y, Lin J, Chen F, Wang S, Li D, Kuang Z, Zhu W, Li Y, Zheng T, Cao W, Zhu B, Tsai E, Fu L, Li M. Structure elucidation and formation mechanistic study of a methylene-bridged pregabalin dimeric degradant in pregabalin extended-release tablets. Int J Pharm 2020; 575:118910. [PMID: 31805310 DOI: 10.1016/j.ijpharm.2019.118910] [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: 08/30/2019] [Revised: 11/01/2019] [Accepted: 11/24/2019] [Indexed: 11/16/2022]
Abstract
During the pharmaceutical development of pregabalin extended-release tablets, an unknown degradant at a relative retention time (RRT) of 11.7 was observed and its nominal amount exceeded the ICH identification threshold in an accelerated stability study. The aim of this study is to identify the structure and investigate the formation mechanism of this impurity for the purpose of developing a chemically stable pharmaceutical product. By utilizing multi-stage LC-MS analysis in conjunction with mechanism-based stress study, the structure of the RRT 11.7 impurity was rapidly identified as a dimeric degradant that is caused by dimerization of two pregabalin molecules with a methylene bridging the two pregabalin moieties. The structure of the dimer was confirmed by 1D and 2D NMR measurement. The formation pathway of the dimeric degradant was also inferred from the mechanism-based stress study, which implicated that the bridging methylene could originate from formaldehyde which might be the culprit that triggers the dimerization in the first place. The subsequent API-excipients compatibility study indicated that the degradant was indeed formed in the compatibility experiments between pregabalin API and two polymeric excipients (PEO and PVPP) that are known to contain residual formaldehyde, but only in the co-presence of another excipient, colloidal silicon dioxide (SiO2). The kinetic behavior of the degradant formation was also investigated and two kinetic models were utilized based on the Arrhenius and Eyring equations, respectively, to calculate the activation energy (Ea) as well as the enthalpy of activation (△H‡), entropy of activation (△S‡), and Gibbs free energy (△G‡) of the degradation reaction. The results of this study would be useful for the understanding of similar dimeric degradant formation in finished products of drug substances containing primary or secondary amine moieties.
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Affiliation(s)
- Yun Tian
- Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Pharmacy, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, PR China; Prinbury Biopharm Co., Ltd.,538 Cailun Road, Pudong, Shanghai 201203, PR China
| | - Jinsheng Lin
- Center of Excellence for Modern Analytical Technologies (CEMAT), Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang 317204, PR China
| | - Feifei Chen
- Center of Excellence for Modern Analytical Technologies (CEMAT), Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang 317204, PR China
| | - Shaolan Wang
- Center of Excellence for Modern Analytical Technologies (CEMAT), Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang 317204, PR China; School of Science, China Pharmaceutical University, 639 Longmian Avenue, Jiangnin District, Nanjing, Jiangsu 210009, PR China
| | - Dan Li
- Center of Excellence for Modern Analytical Technologies (CEMAT), Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang 317204, PR China
| | - Zijian Kuang
- Center of Excellence for Modern Analytical Technologies (CEMAT), Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang 317204, PR China; School of Science, China Pharmaceutical University, 639 Longmian Avenue, Jiangnin District, Nanjing, Jiangsu 210009, PR China
| | - Wenquan Zhu
- Center of Excellence for Modern Analytical Technologies (CEMAT), Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang 317204, PR China
| | - Yue Li
- Prinbury Biopharm Co., Ltd.,538 Cailun Road, Pudong, Shanghai 201203, PR China
| | - Terry Zheng
- Prinbury Biopharm Co., Ltd.,538 Cailun Road, Pudong, Shanghai 201203, PR China
| | - Wei Cao
- Prinbury Biopharm Co., Ltd.,538 Cailun Road, Pudong, Shanghai 201203, PR China
| | - Bob Zhu
- Prinbury Biopharm Co., Ltd.,538 Cailun Road, Pudong, Shanghai 201203, PR China
| | - Eric Tsai
- Prinbury Biopharm Co., Ltd.,538 Cailun Road, Pudong, Shanghai 201203, PR China
| | - Lei Fu
- Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Pharmacy, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, PR China.
| | - Min Li
- Center of Excellence for Modern Analytical Technologies (CEMAT), Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang 317204, PR China; Huahai US, Inc., 700 Atrium Drive, Somerset, NJ 08873, USA.
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13
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Zhong JS, Huang Y, Wan JZ, Yu XY, Yu AL, Zeng HX, Chen ZY, Zhou XR, Ding M. Chromatographic studies of unusual on-column degradation of cefaclor observed in the impurity separation by HPLC. J Pharm Biomed Anal 2019; 176:112818. [PMID: 31446297 DOI: 10.1016/j.jpba.2019.112818] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Revised: 08/16/2019] [Accepted: 08/17/2019] [Indexed: 11/18/2022]
Abstract
An unpredictable ghost peak was intermittently observed during the impurity separation of cefaclor and formulation by high performance liquid chromatography (HPLC) with a content from below the reported threshold to approximately 0.3% in different laboratories. Through a series of investigations, the ghost peak was identified as an unusual on-column degradant of cefaclor formed under elevated column temperature but was not an actual sample impurity. The chemical structure of the degradant was determined by spectroscopic methods, including high resolution mass spectrometry (HRMS) and 1H-NMR. Consequently, the unknown peak was identified as a C-4 oxidative decarboxylation analog of cefaclor. The formation mechanism of the analog is proposed, and it is suggested that elevated column temperature during HPLC analysis has a profound effect on the degradation. Dissolved oxygen in the mobile phase may promote the formation of the ghost peak. The degradation can be suppressed by using a column temperature below 30 °C. Moreover, several other prevention measures are suggested based upon the results of the investigation.
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Affiliation(s)
- Jia-Sheng Zhong
- Research and Development Center, Sinopharm Zhijun (Shenzhen) Pharmaceutical Co., Ltd., Shenzhen 518110, PR China
| | - Yan Huang
- Research and Development Center, Sinopharm Zhijun (Shenzhen) Pharmaceutical Co., Ltd., Shenzhen 518110, PR China
| | - Jin-Zhi Wan
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou 510006, PR China
| | - Xiao-Yang Yu
- Research and Development Center, Sinopharm Zhijun (Shenzhen) Pharmaceutical Co., Ltd., Shenzhen 518110, PR China
| | - Ai-Ling Yu
- Research and Development Center, Sinopharm Zhijun (Shenzhen) Pharmaceutical Co., Ltd., Shenzhen 518110, PR China
| | - Huan-Xiang Zeng
- Research and Development Center, Sinopharm Zhijun (Shenzhen) Pharmaceutical Co., Ltd., Shenzhen 518110, PR China
| | - Zhen-Yang Chen
- Research and Development Center, Sinopharm Zhijun (Shenzhen) Pharmaceutical Co., Ltd., Shenzhen 518110, PR China
| | - Xiang-Rong Zhou
- Research and Development Center, Sinopharm Zhijun (Shenzhen) Pharmaceutical Co., Ltd., Shenzhen 518110, PR China.
| | - Mei Ding
- Research and Development Center, Sinopharm Zhijun (Shenzhen) Pharmaceutical Co., Ltd., Shenzhen 518110, PR China.
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14
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Lin J, Liu X, Wang J, Li D, Zhu W, Chen W, Zhang X, Li Q, Li M. An artifactual solution degradant of pregabalin due to adduct formation with acetonitrile catalyzed by alkaline impurities during HPLC sample preparation. J Pharm Biomed Anal 2019; 175:112788. [PMID: 31382116 DOI: 10.1016/j.jpba.2019.112788] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Revised: 07/17/2019] [Accepted: 07/23/2019] [Indexed: 10/26/2022]
Abstract
During the HPLC related substances testing of pregabalin API, an unknown peak was observed at a level exceeding the identification threshold. Preliminary investigation revealed that this impurity is not a process impurity but rather an artifactual solution degradant or "ghost peak" during the HPLC analysis. By using a strategy that combines LC-PDA/UV-MSn with mechanism-based stress studies, the unknown peak was rapidly identified as a covalent adduct formed between pregabalin and acetonitrile (the latter is a component of the HPLC sample diluent), which is structurally an ethylamidine derivative of pregabalin. It appeared that the formation of this solution degradant was catalyzed by alkaline impurities during the sample preparation. This plausible mechanism was verified by a mechanism-based forced degradation study, in which a base was added into the sample diluent and consequently, the pregabalin-acetonitrile adduct was produced extremely efficiently at a level of ˜92%. Subsequently, the structure of the solution degradant was confirmed as an ethylamidine derivative of pregabalin through characterization by 1D and 2D NMR; the formation of the ethylamidine moiety is apparently via a nucleophilic attack on the cyano group of acetonitrile by the amino group of pregabalin. Due to the extensive presence of primary and secondary amine moieties in drug substances, this kind of artifactual solution degradation would likely occur during the sample preparations of these amine drugs in their HPLC analyses. In a GMP environment, such an event would trigger undesirable out-of-specification (OOS) investigations. The results of this study should help resolve such OOS investigations or prevent their happening from the very beginning. Furthermore, the somewhat surprising finding of the rather facile reaction that produces the ethylamidine moiety using simple alkylnitrile reagents, such as acetonitrile, may be of practical value in the synthesis of alkylamidines.
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Affiliation(s)
- Jinsheng Lin
- Center of Excellence for Modern Analytical Technologies (CEMAT), Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang, 317204, PR China
| | - Xiaofei Liu
- Center of Excellence for Modern Analytical Technologies (CEMAT), Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang, 317204, PR China
| | - Jing Wang
- Center of Excellence for Modern Analytical Technologies (CEMAT), Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang, 317204, PR China
| | - Dan Li
- Center of Excellence for Modern Analytical Technologies (CEMAT), Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang, 317204, PR China
| | - Wenquan Zhu
- Center of Excellence for Modern Analytical Technologies (CEMAT), Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang, 317204, PR China
| | - Wenbin Chen
- Center of Excellence for Modern Analytical Technologies (CEMAT), Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang, 317204, PR China
| | - Xianhua Zhang
- Quality Control Department of Chuannan Site, Zhejiang Huahai Pharmaceutical Co. Ltd., Duqiao, Linhai, Zhejiang, 317016, PR China
| | - Qiangming Li
- Quality Control Department of Chuannan Site, Zhejiang Huahai Pharmaceutical Co. Ltd., Duqiao, Linhai, Zhejiang, 317016, PR China
| | - Min Li
- Center of Excellence for Modern Analytical Technologies (CEMAT), Zhejiang Huahai Pharmaceutical Co. Ltd., Xunqiao, Linhai, Zhejiang, 317204, PR China; Huahai US, Inc., 700 Atrium Drive, Somerset, NJ, 08873, USA.
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