scholarly journals Solubility prediction, solvate and cocrystal screening as tools for rational crystal engineering

2015 ◽  
Vol 67 (6) ◽  
pp. 803-811 ◽  
Author(s):  
Christoph Loschen ◽  
Andreas Klamt
Keyword(s):  
Crystal Engineering ◽  
Solubility Prediction ◽  
Cocrystal Screening

How Many Cocrystals Are We Missing? Assessing Two Crystal Engineering Approaches to Pharmaceutical Cocrystal Screening

2022 ◽  
Author(s):  
Chiara Cappuccino ◽  
David Cusack ◽  
James Flanagan ◽  
Carl Harrison ◽  
Cillian Holohan ◽  
...  
Keyword(s):  
Crystal Engineering ◽  
Pharmaceutical Cocrystal ◽  
Cocrystal Screening

scholarly journals Crystal engineering of nutraceutical phytosterols: new cocrystal solid solutions

CrystEngComm ◽  
2020 ◽  
Vol 22 (25) ◽  
pp. 4210-4214
Author(s):  
Rafael Barbas ◽  
Lídia Bofill ◽  
Dafne de Sande ◽  
Mercè Font-Bardia ◽  
Rafel Prohens
Keyword(s):  
Natural Product ◽  
Solid Solutions ◽  
Crystal Engineering ◽  
Cocrystal Screening

A cocrystal screening of solid solutions of three phytosterols (β-sitosterol, campesterol, stigmasterol) reveals that cocrystal solid solutions are enriched with β-sitosterol with respect to stigmasterol, a natural product with cytotoxicity concerns.

Template mediated crystal engineering

1994 ◽  
Vol 52 ◽  
pp. 480-481
Author(s):  
Brigid R. Heywood ◽  
S. Champ
Keyword(s):  
Crystal Engineering ◽  
Electrostatic Interactions ◽  
Alkyl Chain ◽  
Crystallographic Axis ◽  
Two Dimensional ◽  
Engineering Process ◽  
Solution Interface ◽  
Extensive Program ◽  
Geometric Homology ◽  
Long Alkyl Chain

Recent work on the crystallisation of inorganic crystals under compressed monomolecular surfactant films has shown that two dimensional templates can be used to promote the oriented nucleation of solids. When a suitable long alkyl chain surfactant is cast on the crystallisation media a monodispersied population of crystals forms exclusively at the monolayer/solution interface. Each crystal is aligned with a specific crystallographic axis perpendicular to the plane of the monolayer suggesting that nucleation is facilitated by recognition events between the nascent inorganic solid and the organic template.For example, monolayers of the long alkyl chain surfactant, stearic acid will promote the oriented nucleation of the calcium carbonate polymorph, calcite, on the (100) face, whereas compressed monolayers of n-eicosyl sulphate will induce calcite nucleation on the (001) face, (Figure 1 & 2). An extensive program of research has confirmed the general principle that molecular recognition events at the interface (including electrostatic interactions, geometric homology, stereochemical complementarity) can be used to promote the crystal engineering process.

The Simplest Patterns of Interpenetrated Honeycomb Layers – Counter examples to the Minimal Transitivity Principle?

2018 ◽  
Author(s):  
Igor Baburin
Keyword(s):  
Crystal Engineering ◽  
Structural Chemistry ◽  
Broad Context ◽  
Rigorous Derivation ◽  
New Approach

The paper calls attention to the most symmetric interpenetration patterns of honeycomb layers. To the best of my knowledge, such patterns remained unknown so far. In my contribution a rigorous derivation of such patterns is given that makes use of a new approach to interpenetrating nets. The results are presented in a broad context of structural chemistry and crystal engineering.

Crystal Engineering of Bi2WO6 to Polar Aurivillius-Phase Oxyhalides

2019 ◽  
Author(s):  
Kazuki Morita ◽  
Ji-Sang Park ◽  
Sunghyun Kim ◽  
Kenji Yasuoka ◽  
Aron Walsh
Keyword(s):  
Photocatalytic Activity ◽  
Crystal Engineering ◽  
First Principles ◽  
Parent Compound ◽  
Aurivillius Phase ◽  
Aurivillius Phases ◽  
Charge Neutrality ◽  
Bismuth Oxides ◽  
Structure Surface ◽  
Electric Dipoles

The Aurivillius phases of complex bismuth oxides have attracted considerable attention due to their lattice polarization (ferroelectricity) and photocatalytic activity. We report a first-principles exploration of Bi<sub>2</sub>WO<sub>6</sub> and the replacement of W<sup>6+</sup> by pentavalent (Nb<sup>5+</sup>, Ta<sup>5+</sup>) and tetravalent (Ti<sup>4+</sup>, Sn<sup>4+</sup>) ions, with charge neutrality maintained by the formation of a mixed-anion oxyhalide sublattice. We find that Bi<sub>2</sub>SnO<sub>4</sub>F<sub>2</sub> is thermodynamically unstable, in contrast to Bi<sub>2</sub>TaO<sub>5</sub>F, Bi<sub>2</sub>NbO<sub>5</sub>F and Bi<sub>2</sub>TiO<sub>4</sub>F<sub>2</sub>. The electric dipoles introduced by chemical substitutions in the parent compound are found to suppress the spontaneous polarization from 61.55 μC/cm<sup>2</sup> to below 15.50 μC/cm<sup>2</sup>. Analysis of the trends in electronic structure, surface structure, and ionization potentials are reported. This family of materials can be further extended with control of layer thicknesses and choice of compensating halide species.<br>

Amorphous and Crystalline Particulates: Challenges and Perspectives in Drug Delivery

2017 ◽  
Vol 23 (3) ◽  
pp. 350-361 ◽  
Author(s):  
Hisham Al-Obaidi ◽  
Mridul Majumder ◽  
Fiza Bari
Keyword(s):  
Crystal Engineering ◽  
Drug Carrier ◽  
Solid Dispersions ◽  
Chemical Properties ◽  
Pharmaceutical Product ◽  
Water Soluble ◽  
Amorphous Form ◽  
Physico Chemical ◽  
Water Soluble Drugs ◽  
Amorphous Drug

Crystalline and amorphous dispersions have been the focus of academic and industrial research due to their potential role in formulating poorly water-soluble drugs. This review looks at the progress made starting with crystalline carriers in the form of eutectics moving towards more complex crystalline mixtures. It also covers using glassy polymers to maintain the drug as amorphous exhibiting higher energy and entropy. However, the amorphous form tends to recrystallize on storage, which limits the benefits of this approach. Specific interactions between the drug and the polymer may retard this spontaneous conversion of the amorphous drug. Some studies have shown that it is possible to maintain the drug in the amorphous form for extended periods of time. For the drug and the polymer to form a stable mixture they have to be miscible on a molecular basis. Another form of solid dispersions is pharmaceutical co-crystals, for which research has focused on understanding the chemistry, crystal engineering and physico-chemical properties. USFDA has issued a guidance in April 2013 suggesting that the co-crystals as a pharmaceutical product may be a reality; but just not yet! While some of the research is still oriented towards application of these carriers, understanding the mechanism by which drug-carrier miscibility occurs is also covered. Within this context is the use of thermodynamic models such as Flory-Huggins model with some examples of studies used to predict miscibility.

Sign in / Sign up

Export Citation Format

Share Document