scholarly journals High-Throughput Oil-Encapsulated Nanodroplet Crystallisation for Organic-Soluble Small Molecule Structure Elucidation and Polymorph Screening (ENaCt)

2019 ◽  
Author(s):  
Andrew Tyler ◽  
Ronnie Ragbirsingh ◽  
Charles McMonagle ◽  
Paul Waddell ◽  
Sarah Heaps ◽  
...  
Keyword(s):  
Small Molecules ◽  
High Throughput ◽  
X Ray Diffraction ◽  
Robot Assisted ◽  
Crystal Forms ◽  
X Ray ◽  
Universal Approach ◽  
High Throughput Method ◽  
Crystalline Forms ◽  
Polymorph Screening

Single crystal X-ray diffraction analysis (SCXRD) constitutes a universal approach for the elucidation of molecular structure and for the study of crystalline forms. However, the discovery of viable crystallisation conditions remains both experimentally challenging and resource intensive, in time and quantity of analyte(s). We report a robot-assisted, high-throughput method for the crystallisation of organic-soluble small molecules, employing only micrograms of analyte per experiment. This allows hundreds of crystallisation conditions to be screened in parallel, with minimal overall sample requirements. Crystals suitable for SCXRD analysis are grown from nanolitre droplets of a solution of analyte in organic solvent(s), each of which is encapsulated within an inert oil to control the rate of solvent loss. This encapsulated nanodroplet crystallisation methodology can also be used in the search for new crystal forms, as exemplified through both our discovery of a new (thirteenth) polymorph of the olanzapine precursor ROY and the SCXRD analysis of the “uncrystallisable” agrochemical dithianon.

scholarly journals High-Throughput Oil-Encapsulated Nanodroplet Crystallisation for Organic-Soluble Small Molecule Structure Elucidation and Polymorph Screening (ENaCt)

2019 ◽  
Author(s):  
Andrew Tyler ◽  
Ronnie Ragbirsingh ◽  
Charles McMonagle ◽  
Paul Waddell ◽  
Sarah Heaps ◽  
...  
Keyword(s):  
Small Molecules ◽  
High Throughput ◽  
X Ray Diffraction ◽  
Robot Assisted ◽  
Crystal Forms ◽  
X Ray ◽  
Universal Approach ◽  
High Throughput Method ◽  
Crystalline Forms ◽  
Polymorph Screening

Single crystal X-ray diffraction analysis (SCXRD) constitutes a universal approach for the elucidation of molecular structure and for the study of crystalline forms. However, the discovery of viable crystallisation conditions remains both experimentally challenging and resource intensive, in time and quantity of analyte(s). We report a robot-assisted, high-throughput method for the crystallisation of organic-soluble small molecules, employing only micrograms of analyte per experiment. This allows hundreds of crystallisation conditions to be screened in parallel, with minimal overall sample requirements. Crystals suitable for SCXRD analysis are grown from nanolitre droplets of a solution of analyte in organic solvent(s), each of which is encapsulated within an inert oil to control the rate of solvent loss. This encapsulated nanodroplet crystallisation methodology can also be used in the search for new crystal forms, as exemplified through both our discovery of a new (thirteenth) polymorph of the olanzapine precursor ROY and the SCXRD analysis of the “uncrystallisable” agrochemical dithianon.

scholarly journals Born out of Fire and Ice: Polymorph Studies of the Antiviral Famciclovir

Crystals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 129
Author(s):  
Liana Vella-Zarb ◽  
Ulrich Baisch
Keyword(s):  
Variable Temperature ◽  
Chemical Properties ◽  
Crystal Form ◽  
X Ray Diffraction ◽  
Crystal Forms ◽  
X Ray ◽  
Physical Chemical ◽  
Diffraction Patterns ◽  
Crystalline Forms

There is much interest and focus on solid forms of famciclovir. However, in spite of the abundance of reported differences in oral bioavailability, compressibility, and other physical–chemical properties of the various crystal forms of this drug, very little precise structural analysis is available in the literature to date. The form used in the commercial formulation is the anhydrous form I. Patents and patent applications report three different anhydrous crystalline forms on the basis of unindexed powder diffraction patterns. Single-crystal and variable-temperature X-ray diffraction experiments using the commercially available anhydrous form of famciclovir were carried out and led not only to the crystal structure determination of the anhydrous form I, but also to discovery of a new crystal form of anhydrous famciclovir from powder data.

Crystal Forms of Semisynthetic Ergot Alkaloid Terguride

2002 ◽  
Vol 67 (4) ◽  
pp. 479-489 ◽  
Author(s):  
Michal Hušák ◽  
Bohumil Kratochvíl ◽  
Ivana Císařová ◽  
Ladislav Cvak ◽  
Alexandr Jegorov ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Ergot Alkaloid ◽  
Simplified Model ◽  
Quantum Mechanical ◽  
Quantum Mechanical Calculations ◽  
X Ray Diffraction ◽  
Torsion Angles ◽  
Crystal Forms ◽  
X Ray ◽  
Independent Molecules

Two new structures of semisynthetic ergot alkaloid terguride created by unusual number of symmetry-independent molecules were determined by X-ray diffraction methods at 150 K. Form A (monoclinic, P212121, Z = 12) contains three symmetry-independent terguride molecules and two molecules of water in the asymmetric part of the unit cell. The form CA (monoclinic, P21, Z = 8) is an anhydrate remarkable by the presence of four symmetry-independent molecules in the crystal structure. Conformations of twelve symmetry-independent molecules that were found in four already described terguride structures are compared with torsion angles obtained by ab initio quantum-mechanical calculations for the simplified model of N-cyclohexyl-N'-diethylurea.

scholarly journals A preliminary study on antifungal effect of TiO2-based paints in natural indoor light

2010 ◽  
Vol 12 (4) ◽  
pp. 53-57 ◽  
Author(s):  
Agata Markowska-Szczupak ◽  
Krzysztof Ulfig ◽  
Barbara Grzmil ◽  
Antoni Morawski
Keyword(s):  
Antifungal Activity ◽  
Aspergillus Niger ◽  
Trichoderma Viride ◽  
Photocatalytic Reaction ◽  
X Ray Diffraction ◽  
Antifungal Effect ◽  
X Ray ◽  
Preliminary Study ◽  
Crystalline Forms ◽  
Growth Of Fungi

A preliminary study on antifungal effect of TiO2-based paints in natural indoor light The antifungal activity of four commercial photocatalytic paints (KEIM Ecosil ME, Titanium FA, Photo Silicate and Silicate D) in natural indoor light was investigated. The paints contained TiO2 in rutile and anatase crystalline forms as evidenced by means of the X-ray diffraction analysis. In most cases the paints inhibited growth of fungi viz. Trichoderma viride, Aspergillus niger, Coonemeria crustacea, Eurotium herbariorum, and Dactylomyces sp. The KEIM Ecosil ME paint displayed the highest antifungal effect in the light, which could be explained with the highest anatase content. The paint antifungal activity and the fungal sensitivity to the TiO2-mediated photocatalytic reaction both decreased in the following orders: KEIM Ecosil ME > Titanium FA > Photo Silicate > Silicate D and T. viride > Dactylomyces sp. > A. niger > E. herbariorum.

scholarly journals c-Perpendicular Orientation of Poly(ʟ-lactide) Films

Polymers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1572
Author(s):  
Baku Nagendra ◽  
Paola Rizzo ◽  
Christophe Daniel ◽  
Lucia Baldino ◽  
Gaetano Guerra
Keyword(s):  
Low Temperature ◽  
Film Plane ◽  
Wide Angle ◽  
Two Dimensional ◽  
X Ray Diffraction ◽  
Amorphous Films ◽  
High Transparency ◽  
X Ray ◽  
Crystalline Forms ◽  
Induced Crystallization

Poly(ʟ-lactide) (PLLA) films, even of high thickness, exhibiting co-crystalline and crystalline α phases with their chain axes preferentially perpendicular to the film plane (c⊥ orientation) have been obtained. This c⊥ orientation, unprecedented for PLLA films, can be achieved by the crystallization of amorphous films as induced by low-temperature sorption of molecules being suitable as guests of PLLA co-crystalline forms, such as N,N-dimethylformamide, cyclopentanone or 1,3-dioxolane. This kind of orientation is shown and quantified by two-dimensional wide-angle X-ray diffraction (2D-WAXD) patterns, as taken with the X-ray beam parallel to the film plane (EDGE patterns), which present all the hk0 arcs centered on the meridian. PLLA α-form films, as obtained by low-temperature guest-induced crystallization, also exhibit high transparency, being not far from those of the starting amorphous films.

Adsorption Capacity of Y Zeolite Using Organic Solvents such as Adsorbates

2014 ◽  
Vol 805 ◽  
pp. 641-645
Author(s):  
Ana Paula Araújo ◽  
Aline Cadigena Lima Patrício ◽  
Anna Karoline Freires de Sousa ◽  
Mariaugusta Ferreira Mota ◽  
Meiry Glaúcia Freire Rodrigues
Keyword(s):  
Small Molecules ◽  
Adsorption Capacity ◽  
Selective Adsorption ◽  
X Ray Diffraction ◽  
Y Zeolite ◽  
High Adsorption ◽  
X Ray ◽  
Low Concentrations ◽  
Adsorption Of Nitrogen ◽  
Type Zeolite

The zeolites differ from traditional adsorbents for selective adsorption of small molecules, the high adsorption capacity at low concentrations and affinity for organic compounds and unsaturated polar molecules. In this work a Y-type zeolite was synthesized, characterized by x-ray diffraction, scanning electron microscopy and adsorption of nitrogen and subjected to test adsorption capacity where it was found that the Y zeolite has the potential adsorption capacity compared to other materials being studied and marketed.

scholarly journals Advances in the Use of Microfluidics to Study Crystallization Fundamentals

2019 ◽  
Vol 10 (1) ◽  
pp. 59-83 ◽  
Author(s):  
Nadine Candoni ◽  
Romain Grossier ◽  
Mehdi Lagaize ◽  
Stéphane Veesler
Keyword(s):  
Phase Diagram ◽  
Diffraction Analysis ◽  
High Throughput ◽  
Concentration Measurement ◽  
Ultraviolet Spectroscopy ◽  
X Ray Diffraction ◽  
Chemical Library ◽  
Microfluidic Platform ◽  
X Ray ◽  
Phase Diagram Determination

This review compares droplet-based microfluidic systems used to study crystallization fundamentals in chemistry and biology. An original high-throughput droplet-based microfluidic platform is presented. It uses nanoliter droplets, generates a chemical library, and directly solubilizes powder, thus economizing both material and time. It is compatible with all solvents without the need for surfactant. Its flexibility permits phase diagram determination and crystallization studies (screening and optimizing experiments) and makes it easy to use for nonspecialists in microfluidics. Moreover, it allows concentration measurement via ultraviolet spectroscopy and solid characterization via X-ray diffraction analysis.

Morphology Control of the Nano-MnO2 by Microwave Hydrothermal Synthesis

2012 ◽  
Vol 624 ◽  
pp. 47-50
Author(s):  
Shi Lei Zhang ◽  
Ben Niu ◽  
Enlei Qi ◽  
Lei Wang ◽  
Jie Qiang Wang
Keyword(s):  
Hydrothermal Synthesis ◽  
Energy Dispersive Spectrometer ◽  
Raw Material ◽  
X Ray Diffraction ◽  
Crystal Forms ◽  
X Ray ◽  
Microwave Assisted ◽  
Structure And Morphology ◽  
Microwave Hydrothermal ◽  
Scanning Electron

In this paper, KMnO4 was used as raw material, nano-MnO2 with different morphologies such as flowers globular, hollow tubular and rodlike were obtained by the microwave assisted hydrothermal synthesis under the acidic condition. The crystal structure and morphology of the resultant MnO2 were characterized by X-ray Diffraction (XRD) and Scanning Electron Microscope (SEM), respectively. The elements and content of samples were tested by Energy Dispersive Spectrometer (EDS). The influence of reaction temperature and holding time on crystal forms and morphologies of the MnO2 was analyzed.

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