Suping Ding

Bio: Suping Ding is an academic researcher from Tianjin University. The author has contributed to research in topics: Crystallization & Solubility. The author has an hindex of 5, co-authored 10 publications receiving 117 citations.

Effects of Solvent on Polymorph Formation and Nucleation of Prasugrel Hydrochloride

Abstract: Three intrinsic properties of solvent were used to evaluate the effects of solvent on polymorph formation of prasugrel hydrochloride. In situ Raman spectroscopy, FTIR, and powder X-ray diffraction were used to characterize two solvent-free polymorphs and five solvates of prasugrel hydrochloride, the two of which were reported for the first time. Reactive crystallization in 24 different pure solvents was studied at 313.15 K. It was found that polymorph formation of prasugrel hydrochloride directly depends on the solvents used in the experiments. Form I was obtained in solvents with low values of hydrogen bond donor ability (HBD), while form II was obtained in solvents with high values of HBD. The thermodynamic and kinetic reasons for the solvent effects were explained by using the solubility data and the nucleation experiments. The solubilities of forms I and II were experimentally determined by a gravimetric method, and an equation based on the linear free energy approach for predicting solubility was app...

Formation of Solid Solution and Ternary Phase Diagrams of Anthracene and Phenanthrene in Different Organic Solvents

Abstract: Crash cooling crystallization of different anthracene (ANT) and phenanthrene (PHE) mixtures in toluene, xylene, and N,N-dimethylformamide (DMF) was investigated. The crystals obtained were identified by powder X-ray diffraction, differential scanning calorimetry, and high-performance liquid chromatography. To verify the formation of different solid solutions, ternary phase diagrams of ANT and PHE in toluene, xylene, and DMF at 308.15 K and 0.1 MPa were determined through experiments. Two solid solutions, α and β, respectively, formed at PHE-rich and ANT-rich ends but coexisted in the middle section of the composition. The effect of solvent and separation process optimization of ANT and PHE were further investigated based on the ternary phase diagrams.

Solid–Liquid Phase Equilibrium and Ternary Phase Diagrams of Ibuprofen–Nicotinamide Cocrystals in Ethanol and Ethanol/Water Mixtures at (298.15 and 313.15) K

Abstract: The phase diagrams for ibuprofen (IBU) and nicotinamide (NCT) in both ethanol and ethanol/water mixtures were constructed at (298.15 and 313.15) K under atmospheric pressure using static method. It is revealed that employing solvent mixtures in cocrystallization could significantly affect the symmetry of phase diagrams. In pure ethanol, the two solutes dissolve incongruently and the diagrams are asymmetric, so excessive IBU is needed to isolate cocrystals. However, in ethanol/water mixtures (mass fraction of water was 0.30), the solubility difference between the two components can be leveled out, resulting in more symmetric phase diagrams which can enlarge the processing space for cocrystallization. The solubility of the 1:1 IBU–NCT cocrystal was evaluated as a function of NCT concentration based on the solubility product. These findings are of great importance to develop the cocrystallization process for manufacturing IBU–NCT cocrystal.

Phase Transition Enthalpy Measurements of Organic and Organometallic Compounds. Sublimation, Vaporization and Fusion Enthalpies From 1880 to 2015. Part 1. C1-C10

Abstract: A compendium of phase change enthalpies published in 2010 is updated to include the period 1880–2015. Phase change enthalpies including fusion, vaporization, and sublimation enthalpies are included for organic, organometallic, and a few inorganic compounds. Part 1 of this compendium includes organic compounds from C1 to C10. Part 2 of this compendium, to be published separately, will include organic and organometallic compounds from C11 to C192. Sufficient data are presently available to permit thermodynamic cycles to be constructed as an independent means of evaluating the reliability of the data. Temperature adjustments of phase change enthalpies from the temperature of measurement to the standard reference temperature, T = 298.15 K, and a protocol for doing so are briefly discussed.

Co-crystallization and small molecule crystal form diversity: from pharmaceutical to materials applications

Abstract: Co-crystallization is the supramolecular phenomenon of aggregation of two or more different chemical entities in a crystalline lattice through non-covalent interactions. It encompasses the study of the manifestation of multi-component crystalline solids as well as their design. The chemistry community and the literature suggest cocrystals with reference to co-crystallization products and multi-component crystalline solids. Over the last decade cocrystals have become very popular as a potential new/alternate solid form of pharmaceuticals. However, there is no consensus on what exactly a cocrystal means and what it constitutes across academia, industry and regulatory bodies. On the other hand, cocrystals have been endorsed to the extent that the following facts have been obscured: (1) cocrystals are only one of the putative outcomes of co-crystallization, if at all, and (2) their application goes way beyond pharmaceuticals. Solvates, solid solutions, eutectics, salts, ionic liquids, solid dispersions, supramolecular gelators etc. are among the multifarious products of co-crystallization. The manifestation of these supramolecular/non-covalent crystalline adducts is controlled by the inherent nature of the system (the components involved) besides the surroundings (temperature, solvent, pH etc.); in effect it is a thermodynamic outcome. Each of these adducts, including cocrystals, are unique, exhibit varied physicochemical properties and are amenable to design and therefore have, and potentially find, manifold applications in diverse fields such as organic synthesis & separation, green chemistry, energy storage, solar cells, electronics, luminescent and smart materials, apart from pharmaceuticals. This article highlights the diversity of crystal forms and the utility of small molecule supramolecular combinations.

Engineering Cocrystals of PoorlyWater-Soluble Drugs to Enhance Dissolution in Aqueous Medium.

Abstract: Biopharmaceutics Classification System (BCS) Class II and IV drugs suffer from poor aqueous solubility and hence low bioavailability. Most of these drugs are hydrophobic and cannot be developed into a pharmaceutical formulation due to their poor aqueous solubility. One of the ways to enhance the aqueous solubility of poorlywater-soluble drugs is to use the principles of crystal engineering to formulate cocrystals of these molecules with water-soluble molecules (which are generally called coformers). Many researchers have shown that the cocrystals significantly enhance the aqueous solubility of poorly water-soluble drugs. In this review, we present a consolidated account of reports available in the literature related to the cocrystallization of poorly water-soluble drugs. The current practice to formulate new drug cocrystals with enhanced solubility involves a lot of empiricism. Therefore, in this work, attempts have been made to understand a general framework involved in successful (and unsuccessful) cocrystallization events which can yield different solid forms such as cocrystals, cocrystal polymorphs, cocrystal hydrates/solvates, salts, coamorphous solids, eutectics and solid solutions. The rationale behind screening suitable coformers for cocrystallization has been explained based on the rules of five i.e., hydrogen bonding, halogen bonding (and in general non-covalent bonding), length of carbon chain, molecular recognition points and coformer aqueous solubility. Different techniques to screen coformers for effective cocrystallization and methods to synthesize cocrystals have been discussed. Recent advances in technologies for continuous and solvent-free production of cocrystals have also been discussed. Furthermore, mechanisms involved in solubilization of these solid forms and the parameters influencing dissolution and stability of specific solid forms have been discussed. Overall, this review provides a consolidated account of the rationale for design of cocrystals, past efforts, recent developments and future perspectives for cocrystallization research which will be extremely useful for researchers working in pharmaceutical formulation development.

Phase Transition Enthalpy Measurements of Organic and Organometallic Compounds and Ionic Liquids. Sublimation, Vaporization, and Fusion Enthalpies from 1880 to 2015. Part 2. C11–C192

Abstract: The second part of this compendium concludes with a collection of phase change enthalpies of organic molecules inclusive of C11–C192 reported over the period 1880–2015. Also included are phase change enthalpies including fusion, vaporization, and sublimation enthalpies for organometallic, ionic liquids, and a few inorganic compounds. Paper I of this compendium, published separately, includes organic compounds from C1 to C10 and describes a group additivity method for evaluating solid, liquid, and gas phase heat capacities as well as temperature adjustments of phase changes. Paper II of this compendium also includes an updated version of a group additivity method for evaluating total phase change entropies which together with the fusion temperature can be useful in estimating total phase change enthalpies. Other uses include application in identifying potential substances that either form liquid or plastic crystals or exhibit additional phase changes such as undetected solid–solid transitions or behave ani...