Ketoconazole-Fumaric Acid Pharmaceutical Cocrystal: From Formulation Design for Bioavailability Improvement to Biocompatibility Testing and Antifungal Efficacy Evaluation.

Development of cocrystals through crystal engineering is a viable strategy to formulate poorly water-soluble active pharmaceutical ingredients as stable crystalline solid forms with enhanced bioavailability. This study presents a controlled cocrystallization process by cooling for the 1:1 cocrystal of Ketoconazole, an antifungal class II drug with the Fumaric acid coformer. This was successfully set up following the meta-stable zone width determination in acetone-water 4:6 (/) and pure ethanol.

"Click" access to multilayer functionalized Au surface: A terpyridine patterning example.

This work is focused on self-assembled monolayers (SAMs) fabrication, using two types of Au surfaces, by subsequent attachment of different layers in order to develop a stable platform consisting of covalent multilayer functionalized gold surfaces. The key step in the construction of SAMs is the covalent linkage to the gold surface, via an amino-thiol derivative, of a cyclooctyne unit exhibiting strained triple bonds which react fast (catalysts are not needed) and quantitatively with organic azides and enable the introduction of various chemical functionalized entities on the gold surface. The versatility of the system is demonstrated by the reaction of the cyclooctyne decorated gold surface with an azide functionalized terpyridine followed by step by step complexation with Fe(II) and another terpyridine unit resulting into a multilayer covered gold surface.

Highly sensitive solid forms discrimination on the whole tablet of the active ingredients in quercetin dietary supplements by NMR crystallography approaches.

Similarly to synthetic drugs, the exact crystalline form of active ingredients in solid formulations of dietary supplements may directly influence the dissolution rate, bioavailability, and stability of the final product, but this information is usually not provided by manufacturers. Working on the examples of two commercial quercetin dietary supplements a quick, reliable, and sensitive method is introduced for quercetin solid forms discrimination directly on the marketed products, without the need for prior sample preparation. It exploits the complementarity between solid-state Nuclear Magnetic Resonance (ss-NMR) and Powder X-Ray Diffraction (PXRD), which proved essential for performing a complete and accurate solid-state characterization of the two commercial products, and for obtaining new insights into the complex quercetin solid-forms landscape.

Crystal Structure and Desolvation Behaviour of the Tadalafil Monosolvates with Acetone and Methyl Ethyl Ketone.

Crystal structures of Tadalafil (TDF) monosolvated forms with acetone (ACE) and methyl ethyl ketone (MEK) were determined by single-crystal X-ray diffraction in which same persistent chains of TDF molecules are present as in the reported structures. The solvates crystallize in a higher orthorhombic symmetry than the known forms with monoclinic structures. Weak interactions between TDF and solvent molecules are present in both solvates, leading to slight conformational distortions of TDF molecules.