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Zhang F, Hou W, Yang Z, Wang Z, Chen R, Drioli E, Wang X, Cui Z. Treatment of Aniline Wastewater by Membrane Distillation and Crystallization. MEMBRANES 2023; 13:561. [PMID: 37367765 DOI: 10.3390/membranes13060561] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Revised: 05/23/2023] [Accepted: 05/26/2023] [Indexed: 06/28/2023]
Abstract
Aniline is a highly toxic organic pollutant with "carcinogenic, teratogenic and mutagenesis" characteristics. In the present paper, a membrane distillation and crystallization (MDCr) process was proposed to achieve zero liquid discharge (ZLD) of aniline wastewater. Hydrophobic polyvinylidene fluoride (PVDF) membranes were used in the membrane distillation (MD) process. The effects of the feed solution temperature and flow rate on the MD performance were investigated. The results showed that the flux of the MD process was up to 20 L·m-2·h-1 and the salt rejection was above 99% under the feeding condition of 60 °C and 500 mL/min. The effect of Fenton oxidation pretreatment on the removal rate of aniline in aniline wastewater was also investigated, and the possibility of realizing the ZLD of aniline wastewater in the MDCr process was verified.
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Affiliation(s)
- Fangli Zhang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing 210009, China
- National Engineering Research Center for Special Separation Membrane, Nanjing Tech University, Nanjing 210009, China
| | - Wei Hou
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing 210009, China
- National Engineering Research Center for Special Separation Membrane, Nanjing Tech University, Nanjing 210009, China
| | - Zhonglin Yang
- SINOPEC Nanjing Research Institute of Chemical Industry Co., Ltd., Nanjing 210048, China
| | - Zhaohui Wang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing 210009, China
- National Engineering Research Center for Special Separation Membrane, Nanjing Tech University, Nanjing 210009, China
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing 210009, China
| | - Rizhi Chen
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing 210009, China
- National Engineering Research Center for Special Separation Membrane, Nanjing Tech University, Nanjing 210009, China
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing 210009, China
| | - Enrico Drioli
- Research Institute on Membrane Technology, ITM-CNR, Via Pietro Bucci 17/C, 87036 Rende, Italy
| | - Xiaozu Wang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing 210009, China
- National Engineering Research Center for Special Separation Membrane, Nanjing Tech University, Nanjing 210009, China
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing 210009, China
| | - Zhaoliang Cui
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing 210009, China
- National Engineering Research Center for Special Separation Membrane, Nanjing Tech University, Nanjing 210009, China
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing 210009, China
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Chergaoui S, Debecker DP, Leyssens T, Luis P. Key Parameters Impacting the Crystal Formation in Antisolvent Membrane-Assisted Crystallization. MEMBRANES 2023; 13:140. [PMID: 36837643 PMCID: PMC9964214 DOI: 10.3390/membranes13020140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 01/14/2023] [Accepted: 01/17/2023] [Indexed: 06/18/2023]
Abstract
Antisolvent crystallization is commonly used in the formation of heat-sensitive compounds as it is the case for most active pharmaceutical ingredients. Membranes have the ability to control the antisolvent mass transfer to the reaction medium, providing excellent mixing that inhibits the formation of local supersaturations responsible for the undesired properties of the resulting crystals. Still, optimization of the operating conditions is required. This work investigates the impact of solution velocity, the effect of antisolvent composition, the temperature and gravity, using glycine-water-ethanol as a model crystallization system, and polypropylene flat sheet membranes. Results proved that in any condition, membranes were consistent in providing a narrow crystal size distribution (CSD) with coefficient of variation (CV) in the range of 0.5-0.6 as opposed to 0.7 obtained by batch and drop-by-drop crystallization. The prism-like shape of glycine crystals was maintained as well, but slightly altered when operating at a temperature of 35 °C with the appearance of smoother crystal edges. Finally, the mean crystal size was within 23 to 40 µm and did not necessarily follow a clear correlation with the solution velocities or antisolvent composition, but increased with the application of higher temperature or gravity resistance. Besides, the monoclinic form of α-glycine was perfectly maintained in all conditions. The results at each condition correlated directly with the antisolvent transmembrane flux that ranged between 0.0002 and 0.001 kg/m2. s. In conclusion, membrane antisolvent crystallization is a robust solution offering consistent crystal properties under optimal operating conditions.
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Affiliation(s)
- Sara Chergaoui
- Institute of Mechanics, Materials and Civil Engineering—Materials & Process Engineering (iMMC-IMAP), Université Catholique de Louvain (UCLouvain), Place Sainte Barbe 2, 1348 Louvain-la-Neuve, Belgium
- Research & Innovation Centre for Process Engineering (ReCIPE), Université Catholique de Louvain (UCLouvain), Place Sainte Barbe, 2 bte L5.02.02-B, 1348 Louvain-la-Neuve, Belgium
| | - Damien P. Debecker
- Institute of Condensed Matter and Nanosciences (IMCN), Université Catholique de Louvain (UCLouvain), Place Louis Pasteur, 1 bte L4.01.06, 1348 Louvain-la-Neuve, Belgium
| | - Tom Leyssens
- Institute of Condensed Matter and Nanosciences (IMCN), Université Catholique de Louvain (UCLouvain), Place Louis Pasteur, 1 bte L4.01.06, 1348 Louvain-la-Neuve, Belgium
| | - Patricia Luis
- Institute of Mechanics, Materials and Civil Engineering—Materials & Process Engineering (iMMC-IMAP), Université Catholique de Louvain (UCLouvain), Place Sainte Barbe 2, 1348 Louvain-la-Neuve, Belgium
- Research & Innovation Centre for Process Engineering (ReCIPE), Université Catholique de Louvain (UCLouvain), Place Sainte Barbe, 2 bte L5.02.02-B, 1348 Louvain-la-Neuve, Belgium
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Khellaf M, Huang X, Valour JP, Mangin D, Charcosset C, Chabanon E. Crystallization by selective evaporation using membrane pervaporation: Application to l-glutamic acid to control polymorphism. J Memb Sci 2022. [DOI: 10.1016/j.memsci.2022.121256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Teoh Y, Ayoub G, Huskić I, Titi HM, Nickels CW, Herrmann B, Friščić T. SpeedMixing: Rapid Tribochemical Synthesis and Discovery of Pharmaceutical Cocrystals without Milling or Grinding Media**. Angew Chem Int Ed Engl 2022; 61:e202206293. [DOI: 10.1002/anie.202206293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Indexed: 11/11/2022]
Affiliation(s)
- Yong Teoh
- Department of Chemistry McGill University 801 Sherbrooke St. W. Montreal H3A 0B8 Canada
| | - Ghada Ayoub
- Department of Chemistry McGill University 801 Sherbrooke St. W. Montreal H3A 0B8 Canada
| | - Igor Huskić
- Department of Chemistry McGill University 801 Sherbrooke St. W. Montreal H3A 0B8 Canada
| | - Hatem M. Titi
- Department of Chemistry McGill University 801 Sherbrooke St. W. Montreal H3A 0B8 Canada
| | | | | | - Tomislav Friščić
- Department of Chemistry McGill University 801 Sherbrooke St. W. Montreal H3A 0B8 Canada
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Teoh Y, Ayoub G, Huskic I, Titi HM, Nickels CW, Herrmann B, Friscic T. SpeedMixing: Rapid Tribochemical Synthesis and Discovery of Pharmaceutical Cocrystals without Milling or Grinding Media. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202206293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
| | | | | | | | | | - Brad Herrmann
- Flacktek, Inc. Flacktek, Inc. 1708 SC-11 29356 Landrum UNITED STATES
| | - Tomislav Friscic
- McGill University Chemistry 801 Sherbrooke St. W. H3A 0B8 Montreal CANADA
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Xu L, Li Y, Jing P, Xu G, Zhou Q, Cai Y, Deng X. Terahertz spectroscopic characterizations and DFT calculations of indomethacin cocrystals with nicotinamide and saccharin. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2021; 249:119309. [PMID: 33341744 DOI: 10.1016/j.saa.2020.119309] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Revised: 11/30/2020] [Accepted: 12/03/2020] [Indexed: 06/12/2023]
Abstract
Co-crystallization is an effective strategy to improve the drug properties such as solubility and stability. However, its thermodynamic backgrounds, especially lattice vibration, haven't been fully understood. In this work, indomethacin (IND) cocrystals formed with nicotinamide (NIC) and saccharin (SAC) are successfully characterized by using terahertz spectroscopy. DFT calculations at PBE-D3 level with and without constrained unit cell are performed to predict the absorption peaks at spectral range. The results suggest that the DFT calculations with constrained unit cell achieve a better agreement with experimental observations. Based on the optimized geometries and calculated phonons, the thermodynamic contributions from lattice vibrations to cocrystal formations are further evaluated. The findings reveal that the vibrational energy plays a comparable role with electronic energy, but has an opposite impact on these two cocrystal formations.
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Affiliation(s)
- Li Xu
- Department of Chemical Engineering and Technology, School of Chemistry, Biology and Materials Science, East China University of Technology, Guanglan Avenue 418, Nanchang City 330013, China
| | - Yin Li
- Department of Physics, School of Sciences, Nanchang University, Xuefu Avenue 999, Nanchang City 330031, China.
| | - Peixin Jing
- Department of Chemical Engineering and Technology, School of Chemistry, Biology and Materials Science, East China University of Technology, Guanglan Avenue 418, Nanchang City 330013, China
| | - Guohao Xu
- Department of Chemical Engineering and Technology, School of Chemistry, Biology and Materials Science, East China University of Technology, Guanglan Avenue 418, Nanchang City 330013, China
| | - Qi Zhou
- Department of Physics, School of Sciences, Nanchang University, Xuefu Avenue 999, Nanchang City 330031, China
| | - Yingxiang Cai
- Department of Physics, School of Sciences, Nanchang University, Xuefu Avenue 999, Nanchang City 330031, China
| | - Xiaohua Deng
- Department of Physics, School of Sciences, Nanchang University, Xuefu Avenue 999, Nanchang City 330031, China; Institute of Space Science and Technology, Nanchang University, Xuefu Avenue 999, Nanchang City 330031, China
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Jun BM, Heo J, Park CM, Yoon Y. Comprehensive evaluation of the removal mechanism of carbamazepine and ibuprofen by metal organic framework. CHEMOSPHERE 2019; 235:527-537. [PMID: 31276866 DOI: 10.1016/j.chemosphere.2019.06.208] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Revised: 06/21/2019] [Accepted: 06/26/2019] [Indexed: 06/09/2023]
Abstract
Pharmaceutical products (PhACs) in water sources are considered to be a severe environmental issue. To mitigate this issue, we used a metal-organic framework (MOF) as an adsorbent to remove selected PhACs (i.e., carbamazepine (CBM) and ibuprofen (IBP)). This work was carried out to characterize the MOF, then confirm its feasibility for removing the selected PhACs. In particular, based on practical considerations, we investigated the effects of various water quality conditions, such as solution temperature, pH, ionic strength/background ions, and humic acid. MOF exhibited better removal rates than commercial powder activated carbon (PAC), considering pseudo-second order kinetic model. We clarified the competitive PhACs adsorption mechanisms based on the results obtained under various water quality conditions and found that hydrophobic interactions were the most important factors for both adsorbates. To confirm the practicality of MOF adsorption, we carried out regeneration tests with four adsorption and desorption cycles using acetone as a cleaning solution. Furthermore, to support the results of our regeneration tests, we characterized the MOF samples before and after adsorbate exposure using Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy. Overall, MOF can be used in practical applications as efficient adsorbents to remove PhACs from water sources.
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Affiliation(s)
- Byung-Moon Jun
- Department of Civil and Environmental Engineering, University of South Carolina, Columbia, 300 Main Street, SC, 29208, USA
| | - Jiyong Heo
- Department of Civil and Environmental Engineering, Korea Army Academy at Youngcheon, 495 Hogook-ro, Gokyungmeon, Youngcheon, Gyeongbuk, 38900, Republic of Korea
| | - Chang Min Park
- Department of Environmental Engineering, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu, 41566, Republic of Korea.
| | - Yeomin Yoon
- Department of Civil and Environmental Engineering, University of South Carolina, Columbia, 300 Main Street, SC, 29208, USA.
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Polymorphism in the co-crystallization of the anticonvulsant drug carbamazepine and saccharin using supercritical CO2 as an anti-solvent. J Supercrit Fluids 2018. [DOI: 10.1016/j.supflu.2018.02.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Preparation and Characterization of Cabamazepine Cocrystal in Polymer Solution. Pharmaceutics 2017; 9:pharmaceutics9040054. [PMID: 29194387 PMCID: PMC5750660 DOI: 10.3390/pharmaceutics9040054] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2017] [Revised: 11/13/2017] [Accepted: 11/29/2017] [Indexed: 11/17/2022] Open
Abstract
In this study, we attempted to prepare carbamazepine (CBZ) cocrystal through the solution method in ethanol-water solvent mixture (volume ratio 1:1) and polyvinyl pyrrolidone (PVP) solution. Nicotinamide (NIC) and saccharin (SAC) were selected as cocrystal coformers. Cocrystal screening products were characterized by Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), and Powder X-ray Diffraction (PXRD) techniques. Characterization results show that in ethanol-water solvent mixture, pure CBZ-NIC cocrystal can be prepared, while CBZ-SAC cocrystal cannot be obtained. The addition of PVP can inhibit CBZ-NIC cocrystal formation and facilitate CBZ-SAC cocrystal formation.
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Covaci OI, Mitran RA, Buhalteanu L, Dumitrescu DG, Shova S, Manta CM. Bringing new life into old drugs: a case study on nifuroxazide polymorphism. CrystEngComm 2017. [DOI: 10.1039/c7ce00303j] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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Lange L, Heisel S, Sadowski G. Predicting the Solubility of Pharmaceutical Cocrystals in Solvent/Anti-Solvent Mixtures. Molecules 2016; 21:molecules21050593. [PMID: 27164075 PMCID: PMC6273375 DOI: 10.3390/molecules21050593] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Revised: 04/28/2016] [Accepted: 04/29/2016] [Indexed: 11/24/2022] Open
Abstract
In this work, the solubilities of pharmaceutical cocrystals in solvent/anti-solvent systems were predicted using PC-SAFT in order to increase the efficiency of cocrystal formation processes. Modeling results and experimental data were compared for the cocrystal system nicotinamide/succinic acid (2:1) in the solvent/anti-solvent mixtures ethanol/water, ethanol/acetonitrile and ethanol/ethyl acetate at 298.15 K and in the ethanol/ethyl acetate mixture also at 310.15 K. The solubility of the investigated cocrystal slightly increased when adding small amounts of anti-solvent to the solvent, but drastically decreased for high anti-solvent amounts. Furthermore, the solubilities of nicotinamide, succinic acid and the cocrystal in the considered solvent/anti-solvent mixtures showed strong deviations from ideal-solution behavior. However, by accounting for the thermodynamic non-ideality of the components, PC-SAFT is able to predict the solubilities in all above-mentioned solvent/anti-solvent systems in good agreement with the experimental data.
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Affiliation(s)
- Linda Lange
- Department of Chemical and Biochemical Engineering, Laboratory of Thermodynamics, TU Dortmund University, Emil-Figge-Str. 70, D-44227 Dortmund, Germany.
| | - Stefan Heisel
- Department of Chemical and Biochemical Engineering, Laboratory of Thermodynamics, TU Dortmund University, Emil-Figge-Str. 70, D-44227 Dortmund, Germany.
| | - Gabriele Sadowski
- Department of Chemical and Biochemical Engineering, Laboratory of Thermodynamics, TU Dortmund University, Emil-Figge-Str. 70, D-44227 Dortmund, Germany.
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Lee MJ, Wang IC, Kim MJ, Kim P, Song KH, Chun NH, Park HG, Choi GJ. Controlling the polymorphism of carbamazepine-saccharin cocrystals formed during antisolvent cocrystallization using kinetic parameters. KOREAN J CHEM ENG 2015. [DOI: 10.1007/s11814-014-0384-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Abstract
Crystallography is a major tool for structure-driven drug design, as it allows knowledge of the 3D structure of protein targets and protein-ligand complexes. However, the route for crystal structure determination involves many steps, some of which may hamper its high-throughput use. Recent efforts have produced significant advances in experimental and computational tools and protocols. They include automatic crystallization tools, faster data collection devices, more efficient phasing methods and improved ligand-fitting procedures. The timescales of drug-discovery processes have been also reduced by using a fragment-based screening approach. Herein, the achievements in protein crystallography over the last 5 years are reviewed, and advantages and disadvantages of the fragment-based approaches to drug discovery that make use of x-ray crystallography as a primary screening method are examined. In particular, in some detail, five recent case studies pertaining to the development of new hits or leads in relevant therapeutic areas, such as cancer, immune response, inflammation, metabolic syndrome and neurology are described.
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Wang IC, Lee MJ, Sim SJ, Kim WS, Chun NH, Choi GJ. Anti-solvent co-crystallization of carbamazepine and saccharin. Int J Pharm 2013; 450:311-22. [PMID: 23598078 DOI: 10.1016/j.ijpharm.2013.04.012] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2013] [Revised: 03/25/2013] [Accepted: 04/09/2013] [Indexed: 11/24/2022]
Abstract
The co-crystal approach has been investigated extensively over the past decade as one of the most promising methods to enhance the dissolution properties of insoluble drug substances. Co-crystal powders are typically produced by mechanical grinding (neat or wet) or a solution method (evaporation or cooling). In this study, high-purity carbamazepine-saccharin (CBZ-SAC) co-crystals were manufactured by a novel method, anti-solvent addition. Among various solvents, methanol was found to perform well with water as the anti-solvent for the co-crystallization of CBZ and SAC. When water was added to the methanol solution of CBZ and SAC at room temperature under agitation, nucleation of CBZ-SAC co-crystals occurred within 2-3 min. Co-crystallization was complete after 30 min, giving a solid yield as high as 84.5% on a CBZ basis. The effects of initial concentrations, focusing on the SAC/CBZ ratio, were examined to establish optimal conditions. The whole anti-solvent co-crystallization process was monitored at-line via ATR-FTIR analysis of regularly sampled solutions. The nucleation and crystal growth of CBZ-SAC co-crystals were detected by a significant increase in absorption in the range of 2400-2260 cm(-1), associated with the formation of hydrogen bonds between the carbonyl group in CBZ and the N-H of SAC. When CBZ hydrates were formed as impurities during anti-solvent co-crystallization, the hydrogen bonding between methanol and water was reduced greatly, primarily due to the incorporation of water molecules into the CBZ crystal lattice. In conclusion, an anti-solvent approach can be used to produce highly pure CBZ-SAC co-crystal powders with a high solid yield.
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Affiliation(s)
- In-Chun Wang
- Department of Smart Food & Drugs, Inje University, Gimhae, Gyeongnam 621-749, Republic of Korea
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Caliandro R, Di Profio G, Nicolotti O. Multivariate analysis of quaternary carbamazepine-saccharin mixtures by X-ray diffraction and infrared spectroscopy. J Pharm Biomed Anal 2013; 78-79:269-79. [PMID: 23518290 DOI: 10.1016/j.jpba.2013.01.042] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2012] [Revised: 01/25/2013] [Accepted: 01/28/2013] [Indexed: 11/27/2022]
Abstract
Co-crystallization brings new opportunities for improving the solubility and dissolution rate of drugs with the chance of finely tuning some relevant chemical-physical properties of mixtures containing bioactive compounds. As co-crystallization process involves several molecular species, which are generally solid at room conditions, its control requires accurate knowledge and monitoring of the different phase that might appear during the formulation stage. In the present study the suitability of X-ray powder diffraction (XRPD) and Fourier-transformed infrared (FTIR) spectroscopy in quantifying mixtures of carbamazepine polymorphs (forms I and III), saccharin, and carbamazepine-saccharin cocrystals (form I) is assessed. Quaternary crystalline mixtures typically produced in the process of co-crystal production were analyzed by multivariate methods. Principal component analysis (PCA) was used for the identification of the crystal phases, while unsupervised simultaneous fitting of the spectra from pure phases, or supervised partial least squares (PLS) methods were used for their quantitative determination. The performance of data analysis was enhanced by applying peculiar pre-processing methods, such as SNIP filtering in case of FTIR and PCA filtering in case of XRPD. It was found that, for XRPD data, the automatic multi-fitting procedures and PLS models developed in this study are able to quantify single phases in mixtures to an accuracy level comparable to that obtained by the widely used Rietveld method, which, however, requires knowledge of the crystal structures. For FTIR data the results here obtained prove that this technique can be used as a fast method for polymorph characterization.
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