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Maunder JJ, Aguilar JA, Hodgkinson P, Cooper SJ. Structured ternary fluids as nanocrystal incubators for enhanced crystallization control. Chem Sci 2022; 13:13132-13140. [DOI: 10.1039/d2sc04413g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2022] [Accepted: 10/23/2022] [Indexed: 11/21/2022] Open
Abstract
Crystallization in structured ternary fluids can proceed via higher nucleation rate and slower crystal growth pathways that are impossible to access in normal unstructured solutions. Hence, structured ternary fluids can act as nanocrystal incubators.
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Affiliation(s)
- J. J. Maunder
- Department of Chemistry, University of Durham, Durham DH1 3LE, UK
| | - J. A. Aguilar
- Department of Chemistry, University of Durham, Durham DH1 3LE, UK
| | - P. Hodgkinson
- Department of Chemistry, University of Durham, Durham DH1 3LE, UK
| | - S. J. Cooper
- Department of Chemistry, University of Durham, Durham DH1 3LE, UK
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2
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Affiliation(s)
- Elena Boldyreva
- Novosibirsk State University ul. Pirogova, 2 Novosibirsk 630090 Russian Federation
- Boreskov Institute of Catalysis Siberian Branch of Russian Academy of Sciences Lavrentieva ave., 5 Novosibirsk 630090 Russian Federation
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3
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Chen F, Man N, Yang C, Cao R, Lian Y, Zhang JH, Lai W, Xue R, Ma Y. Synthesis of γ Phase and Amorphous Solid Dispersion of Glycine from α-Glycine During the Solvent-Free Ball Milling Process. J Pharm Sci 2021; 110:3171-3175. [PMID: 34139259 DOI: 10.1016/j.xphs.2021.06.023] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 06/09/2021] [Accepted: 06/10/2021] [Indexed: 12/01/2022]
Abstract
Nano α-glycine crystals, γ-glycine crystals, and amorphous solid dispersion (ASD) of glycine were prepared through solvent-free ball milling of commercial α-glycine. The solid-state polymorph conversion of glycine from α to γ was completely realized by ball milling with 0.2 wt.% NaCl for 1 h or by ball milling with 0.02 wt.% NaCl for 1 h with subsequent storage for one week. The ASD of glycine was prepared by ball milling α-glycine with an equal amount of CaCl2 for 1 h. We studied the effect of inorganic salt types and their concentrations on the extent of polymorph conversion and amorphization of glycine in our experiments. This solvent-free ball milling method could be used for the synthesis of polymorphs and amorphous phase of drugs and other organic materials.
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Affiliation(s)
- Fenghua Chen
- School of Resources and Chemical Engineering, Sanming University, Sanming 365004, Fujian, China.
| | - Nuo Man
- School of Resources and Chemical Engineering, Sanming University, Sanming 365004, Fujian, China
| | - Chenmei Yang
- School of Resources and Chemical Engineering, Sanming University, Sanming 365004, Fujian, China
| | - Renfen Cao
- School of Resources and Chemical Engineering, Sanming University, Sanming 365004, Fujian, China
| | - Yuezong Lian
- College of Architecture and Civil Engineering, Sanming University, Sanming 365004, Fujian, China
| | - Jian-Han Zhang
- School of Resources and Chemical Engineering, Sanming University, Sanming 365004, Fujian, China
| | - Wenzhong Lai
- School of Resources and Chemical Engineering, Sanming University, Sanming 365004, Fujian, China
| | - Rongrong Xue
- School of Resources and Chemical Engineering, Sanming University, Sanming 365004, Fujian, China.
| | - Yurong Ma
- School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China
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4
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Understanding the Salt-Dependent Outcome of Glycine Polymorphic Nucleation. Pharmaceutics 2021; 13:pharmaceutics13020262. [PMID: 33671970 PMCID: PMC7919016 DOI: 10.3390/pharmaceutics13020262] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 02/06/2021] [Accepted: 02/08/2021] [Indexed: 11/17/2022] Open
Abstract
The salt-dependent polymorphs of glycine crystals formed from bulk solutions have been a longstanding riddle. In this study, in order to shed fresh light, we studied the effects of seven common salts on primary nucleation of the metastable α-glycine and the stable γ-glycine. Our nucleation experiments and in-depth data analyses enabled us to reveal that (NH4)2SO4, NaCl and KNO3, in general, promote γ-glycine primary nucleation very significantly while simultaneously inhibiting α-glycine primary nucleation, thereby explaining why these three salts induce γ-glycine readily. In comparison, Ca(NO3)2 and MgSO4 also promote γ-glycine and inhibit α-glycine primary nucleation but not sufficiently to induce γ-glycine. More interestingly, Na2SO4 and K2SO4 promote not only γ-glycine but also α-glycine primary nucleation, which is unexpected and presents a rare case where a single additive promotes the nucleation of both polymorphs. As a result, the promoting effects of Na2SO4 and K2SO4 on γ-glycine do not enable γ-glycine nucleation to be more competitive than α-glycine nucleation, with γ-glycine failing to appear. These observations help us to better understand salt-governed glycine polymorphic selectivity.
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5
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Anbu Arasi M, Alagar M, Raja Pugalenthi M. Growth of γ-glycine single crystals using the tailored additive of potassium chloride and L-Proline and analyzing micro structural, optical, mechanical and electrical parameters. Chem Phys Lett 2021. [DOI: 10.1016/j.cplett.2020.138301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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6
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Bishara H, Nagel A, Levanon M, Berger S. Amino acids nanocrystals for piezoelectric detection of ultra-low mechanical pressure. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2020; 108:110468. [PMID: 31923955 DOI: 10.1016/j.msec.2019.110468] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 10/17/2019] [Accepted: 11/19/2019] [Indexed: 11/27/2022]
Abstract
Developing biocompatible nano-materials with the ability to detect ultra-low mechanical pressure is promising for biomedical sensors. This paper reports the detection of pressure as low as 1 Pa in the environmental pressure of 1 atm (10-3% pressure change) by nanocrystals of amino acids glycine and alanine through the piezoelectric effect. Piezoelectricity enables detection of pressure by a change of dielectric polarization when the material is subjected to external pressure. This work exploits the non-centro-symmetric structure of some amino acids and their weak hydrogen bonds to develop sensitive mechanical pressure sensors. The β-glycine and l-alanine nanocrystals were grown from aqueous solution inside porous alumina substrate. The nanocrystals exhibit pronounced preferred crystallographic orientation. The sensitive piezoelectric response to ultra-low mechanical pressure is discussed based on atomic and crystal symmetry considerations.
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Affiliation(s)
- Hanna Bishara
- Faculty of Materials Science and Engineering, Technion, 32000 Haifa, Israel.
| | - Alina Nagel
- Faculty of Materials Science and Engineering, Technion, 32000 Haifa, Israel
| | - Maya Levanon
- Faculty of Materials Science and Engineering, Technion, 32000 Haifa, Israel
| | - Shlomo Berger
- Faculty of Materials Science and Engineering, Technion, 32000 Haifa, Israel
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7
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Broadhurst ET, Xu H, Clabbers MTB, Lightowler M, Nudelman F, Zou X, Parsons S. Polymorph evolution during crystal growth studied by 3D electron diffraction. IUCRJ 2020; 7:5-9. [PMID: 31949899 PMCID: PMC6949601 DOI: 10.1107/s2052252519016105] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Accepted: 11/29/2019] [Indexed: 05/24/2023]
Abstract
3D electron diffraction (3DED) has been used to follow polymorph evolution in the crystallization of glycine from aqueous solution. The three polymorphs of glycine which exist under ambient conditions follow the stability order β < α < γ. The least stable β polymorph forms within the first 3 min, but this begins to yield the α-form after only 1 min more. Both structures could be determined from continuous rotation electron diffraction data collected in less than 20 s on crystals of thickness ∼100 nm. Even though the γ-form is thermodynamically the most stable polymorph, kinetics favour the α-form, which dominates after prolonged standing. In the same sample, some β and one crystallite of the γ polymorph were also observed.
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Affiliation(s)
- Edward T. Broadhurst
- EaStCHEM School of Chemistry and Centre for Science at Extreme Conditions, The University of Edinburgh, King’s Buildings, West Mains Road, Edinburgh EH9 3FJ, UK
| | - Hongyi Xu
- Department of Materials and Environmental Chemistry, Stockholm University, Stockholm SE-106 91, Sweden
| | - Max T. B. Clabbers
- Department of Materials and Environmental Chemistry, Stockholm University, Stockholm SE-106 91, Sweden
| | - Molly Lightowler
- Department of Materials and Environmental Chemistry, Stockholm University, Stockholm SE-106 91, Sweden
| | - Fabio Nudelman
- EaStCHEM School of Chemistry and Centre for Science at Extreme Conditions, The University of Edinburgh, King’s Buildings, West Mains Road, Edinburgh EH9 3FJ, UK
| | - Xiaodong Zou
- Department of Materials and Environmental Chemistry, Stockholm University, Stockholm SE-106 91, Sweden
| | - Simon Parsons
- EaStCHEM School of Chemistry and Centre for Science at Extreme Conditions, The University of Edinburgh, King’s Buildings, West Mains Road, Edinburgh EH9 3FJ, UK
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8
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Bai C, Wang C, Zheng T, Hu Q. Growth of β-glycine crystals promoted by standing surface acoustic waves (SSAWs). CrystEngComm 2018. [DOI: 10.1039/c7ce02038d] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Glycine has three polymorphic forms, the α-, β- and γ-phase, where the β-phase is less stable than the other two, but it is the most useful one.
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Affiliation(s)
- Cheng Bai
- State Key Laboratory for Manufacturing Systems Engineering
- Xi'an Jiaotong University
- Xi'an 710049
- People's Republic of China
| | - Chaohui Wang
- State Key Laboratory for Manufacturing Systems Engineering
- Xi'an Jiaotong University
- Xi'an 710049
- People's Republic of China
| | - Tengfei Zheng
- State Key Laboratory for Manufacturing Systems Engineering
- Xi'an Jiaotong University
- Xi'an 710049
- People's Republic of China
| | - Qiao Hu
- State Key Laboratory for Manufacturing Systems Engineering
- Xi'an Jiaotong University
- Xi'an 710049
- People's Republic of China
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9
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Little LJ, King AAK, Sear RP, Keddie JL. Controlling the crystal polymorph by exploiting the time dependence of nucleation rates. J Chem Phys 2017; 147:144505. [DOI: 10.1063/1.4993566] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Laurie J. Little
- Department of Physics, University of Surrey, Guildford, Surrey GU2 7XH, United Kingdom
| | - Alice A. K. King
- Department of Physics, University of Surrey, Guildford, Surrey GU2 7XH, United Kingdom
- Department of Physics and Astronomy, University of Sussex, Brighton BN1 9RH, United Kingdom
| | - Richard P. Sear
- Department of Physics, University of Surrey, Guildford, Surrey GU2 7XH, United Kingdom
| | - Joseph L. Keddie
- Department of Physics, University of Surrey, Guildford, Surrey GU2 7XH, United Kingdom
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10
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Harris KDM, Hughes CE, Williams PA, Edwards-Gau GR. `NMR Crystallization': in-situ NMR techniques for time-resolved monitoring of crystallization processes. ACTA CRYSTALLOGRAPHICA SECTION C-STRUCTURAL CHEMISTRY 2017; 73:137-148. [PMID: 28257007 DOI: 10.1107/s2053229616019811] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Accepted: 12/12/2016] [Indexed: 11/10/2022]
Abstract
Solid-state NMR spectroscopy is a well-established and versatile technique for studying the structural and dynamic properties of solids, and there is considerable potential to exploit the power and versatility of solid-state NMR for in-situ studies of chemical processes. However, a number of technical challenges are associated with adapting this technique for in-situ studies, depending on the process of interest. Recently, an in-situ solid-state NMR strategy for monitoring the evolution of crystallization processes has been developed and has proven to be a promising approach for identifying the sequence of distinct solid forms present as a function of time during crystallization from solution, and for the discovery of new polymorphs. The latest development of this technique, called `CLASSIC' NMR, allows the simultaneous measurement of both liquid-state and solid-state NMR spectra as a function of time, thus yielding complementary information on the evolution of both the liquid phase and the solid phase during crystallization from solution. This article gives an overview of the range of NMR strategies that are currently available for in-situ studies of crystallization processes, with examples of applications that highlight the potential of these strategies to deepen our understanding of crystallization phenomena.
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Affiliation(s)
- Kenneth D M Harris
- School of Chemistry, Cardiff University, Park Place, Cardiff CF10 3AT, Wales
| | - Colan E Hughes
- School of Chemistry, Cardiff University, Park Place, Cardiff CF10 3AT, Wales
| | - P Andrew Williams
- School of Chemistry, Cardiff University, Park Place, Cardiff CF10 3AT, Wales
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11
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Liu Y, van den Berg MH, Alexander AJ. Supersaturation dependence of glycine polymorphism using laser-induced nucleation, sonocrystallization and nucleation by mechanical shock. Phys Chem Chem Phys 2017; 19:19386-19392. [DOI: 10.1039/c7cp03146g] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Nucleation of glycine by laser, ultrasound and mechanical shock exhibits a transition from the alpha to the gamma polymorph with increasing supersaturation.
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Affiliation(s)
- Yao Liu
- School of Chemistry
- University of Edinburgh
- David Brewster Road
- Scotland
- UK
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12
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Huo JZ, Su XM, Wu XX, Liu YY, Ding B. Hydrothermal synthesis and characterization of a series of luminescent Ag(i) coordination polymers with two new multidentate bis-(1,2,3-triazole) ligands: structural diversity, polymorphism and photoluminescent sensing. CrystEngComm 2016. [DOI: 10.1039/c6ce01275b] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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13
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Han G, Chow PS, Tan RBH. Salt-dependent growth kinetics in glycine polymorphic crystallization. CrystEngComm 2016. [DOI: 10.1039/c5ce01974e] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Divalent cation salts inhibit the growth of α-glycine far less severely than that of γ-glycine, causing α-glycine to have a greater competitive advantage over γ-glycine, thus further reinforcing the preferential formation of α-glycine on a relative basis.
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Affiliation(s)
- Guangjun Han
- Institute of Chemical and Engineering Sciences
- A*STAR (Agency for Science, Technology and Research)
- Jurong Island, 627833 Singapore
| | - Pui Shan Chow
- Institute of Chemical and Engineering Sciences
- A*STAR (Agency for Science, Technology and Research)
- Jurong Island, 627833 Singapore
| | - Reginald B. H. Tan
- Institute of Chemical and Engineering Sciences
- A*STAR (Agency for Science, Technology and Research)
- Jurong Island, 627833 Singapore
- Department of Chemical and Biomolecular Engineering
- National University of Singapore
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14
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He X, Benniston AC, Saarenpää H, Lemmetyinen H, Tkachenko NV, Baisch U. Polymorph crystal packing effects on charge transfer emission in the solid state. Chem Sci 2015; 6:3525-3532. [PMID: 29511514 PMCID: PMC5814771 DOI: 10.1039/c5sc01151e] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 04/18/2015] [Indexed: 11/30/2022] Open
Abstract
Condensation of 1,8-naphthalic anhydride with N,N-(dimethylamino)aniline produced the donor-acceptor compound DMIM, which crystallised from a chloroform-diethyl ether mixture to afford two different coloured crystal polymorphs. Crystals for one polymorph are small and green, whereas the other crystals are orange and needle-like. X-ray crystal structures for both polymorphs were determined. The donor N,N-dimethylaniline and acceptor naphthalimide groups are twisted with respect to each other; the degree of twist is marginally different for the two structures. The orange crystal polymorph crystallises in the monoclinic space group C2/c and contains two slightly different molecular conformers in the unit cell (calculated density is 1.410 g cm-3). The green crystal polymorph crystallises in the triclinic space group P1 and contains only one type of molecule in the unit cell (calculated density is 1.401 g cm-3). The crystal packing motifs for the two polymorphs are subtly different, explaining the small variance in the observed densities. Very weak room temperature emission was observed for DMIM in a CHCl3 solution, but crystals deposited on a glass slide glowed when irradiated at 488 nm using a fluorescence microscope. Disparate solid-state emission spectra and lifetimes for the two polymorphic crystal forms are observed for the dyad. The emission is assigned to charge recombination fluorescence from a charge transfer state.
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Affiliation(s)
- Xiaoyan He
- Molecular Photonics Laboratory , School of Chemistry , Newcastle University , Newcastle upon Tyne , NE1 7RU , UK
| | - Andrew C Benniston
- Molecular Photonics Laboratory , School of Chemistry , Newcastle University , Newcastle upon Tyne , NE1 7RU , UK
| | - Hanna Saarenpää
- Department of Chemistry and Bioengineering , Tampere University of Technology , Tampere , Finland
| | - Helge Lemmetyinen
- Department of Chemistry and Bioengineering , Tampere University of Technology , Tampere , Finland
| | - Nikolia V Tkachenko
- Department of Chemistry and Bioengineering , Tampere University of Technology , Tampere , Finland
| | - Ulrich Baisch
- Molecular Photonics Laboratory , School of Chemistry , Newcastle University , Newcastle upon Tyne , NE1 7RU , UK
- Department of Chemistry , University of Malta , Msida , MSD 2080 , Malta
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15
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Devi KR, Srinivasan K. Impact of malonic acid on the segregation of glycine polymorphs - Analytical assisted molecular approach. CRYSTAL RESEARCH AND TECHNOLOGY 2015. [DOI: 10.1002/crat.201400400] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- K. Renuka Devi
- Crystal Growth Laboratory, Department of Physics, School of Physical Sciences, Bharathiar University; Coimbatore 641 046 Tamil Nadu India
| | - K. Srinivasan
- Crystal Growth Laboratory, Department of Physics, School of Physical Sciences, Bharathiar University; Coimbatore 641 046 Tamil Nadu India
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16
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Hughes CE, Williams PA, Keast VL, Charalampopoulos VG, Edwards-Gau GR, Harris KDM. New in situ solid-state NMR techniques for probing the evolution of crystallization processes: pre-nucleation, nucleation and growth. Faraday Discuss 2015; 179:115-40. [DOI: 10.1039/c4fd00215f] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The application of in situ techniques for investigating crystallization processes promises to yield significant new insights into fundamental aspects of crystallization science. With this motivation, we recently developed a new in situ solid-state NMR technique that exploits the ability of NMR to selectively detect the solid phase in heterogeneous solid–liquid systems (of the type that exist during crystallization from solution), with the liquid phase “invisible” to the measurement. As a consequence, the technique allows the first solid particles produced during crystallization to be observed and identified, and allows the evolution of different solid phases (e.g., polymorphs) present during the crystallization process to be monitored as a function of time. This in situ solid-state NMR strategy has been demonstrated to be a powerful approach for establishing the sequence of solid phases produced during crystallization and for the discovery of new polymorphs. The most recent advance of the in situ NMR methodology has been the development of a strategy (named “CLASSIC NMR”) that allows both solid-state NMR and liquid-state NMR spectra to be measured (essentially simultaneously) during the crystallization process, yielding information on the complementary changes that occur in both the solid and liquid phases as a function of time. In this article, we present new results that highlight the application of our in situ NMR techniques to successfully unravel different aspects of crystallization processes, focusing on: (i) the application of a CLASSIC NMR approach to monitor competitive inclusion processes in solid urea inclusion compounds, (ii) exploiting liquid-state NMR to gain insights into co-crystal formation between benzoic acid and pentafluorobenzoic acid, and (iii) applications of in situ solid-state NMR for the discovery of new solid forms of trimethylphosphine oxide and l-phenylalanine. Finally, the article discusses a number of important fundamental issues relating to practical aspects, the interpretation of results and the future scope of these techniques, including: (i) an assessment of the smallest size of solid particle that can be detected in in situ solid-state NMR studies of crystallization, (ii) an appraisal of whether the rapid sample spinning required by the NMR measurement technique may actually influence or perturb the crystallization behaviour, and (iii) a discussion of factors that influence the sensitivity and time-resolution of in situ solid-state NMR experiments.
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Duff N, Dahal YR, Schmit JD, Peters B. Salting out the polar polymorph: analysis by alchemical solvent transformation. J Chem Phys 2014; 140:014501. [PMID: 24410227 DOI: 10.1063/1.4853775] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
We computationally examine how adding NaCl to an aqueous solution with α- and γ-glycine nuclei alters the structure and interfacial energy of the nuclei. The polar γ-glycine nucleus in pure aqueous solution develops a melted layer of amorphous glycine around the nucleus. When NaCl is added, a double layer is formed that stabilizes the polar glycine polymorph and eliminates the surface melted layer. In contrast, the non-polar α-glycine nucleus is largely unaffected by the addition of NaCl. To quantify the stabilizing effect of NaCl on γ-glycine nuclei, we alchemically transform the aqueous glycine solution into a brine solution of glycine. The alchemical transformation is performed both with and without a nucleus in solution and for nuclei of α-glycine and γ-glycine polymorphs. The calculations show that adding 80 mg/ml NaCl reduces the interfacial free energy of a γ-glycine nucleus by 7.7 mJ/m(2) and increases the interfacial free energy of an α-glycine nucleus by 3.1 mJ/m(2). Both results are consistent with experimental reports on nucleation rates which suggest: J(α, brine) < J(γ, brine) < J(α, water). For γ-glycine nuclei, Debye-Hückel theory qualitatively, but not quantitatively, captures the effect of salt addition. Only the alchemical solvent transformation approach can predict the results for both polar and non-polar polymorphs. The results suggest a general "salting out" strategy for obtaining polar polymorphs and also a general approach to computationally estimate the effects of solvent additives on interfacial free energies for nucleation.
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Affiliation(s)
- Nathan Duff
- Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina 27695, USA
| | - Yuba Raj Dahal
- Department of Physics, Kansas State University, Manhattan, Kansas 66506, USA
| | - Jeremy D Schmit
- Department of Physics, Kansas State University, Manhattan, Kansas 66506, USA
| | - Baron Peters
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, USA
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18
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Renuka Devi K, Srinivasan K. A novel approach to understand the nucleation kinetics of α and γ polymorphs of glycine from aqueous solution in the presence of a selective additive through charge compensation mechanism. CrystEngComm 2014. [DOI: 10.1039/c3ce41235k] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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