Trimesic Acid as a Building Block for Ternary and Quaternary Salts and Salt Cocrystals.

In the field of cocrystals, the synthon-based design of two-component crystals is well established and the interest is now shifting toward higher order cocrystals as the next challenge. Carboxylic acids form a robust synthon with pyridyl coformers and interact with 2-aminopyrimidines through a pair of strong, charge-assisted hydrogen bonds. In this work we describe the formation of higher order salts and salt cocrystals of trimesic acid using 2,4-diaminopyrimidine (pyrimethamine, trimethoprim) and pyridyl (4,4'-bipyridine, 1,2-di(4-pyridyl)ethylene, 1,3-di(4-pyridyl)propane, 4-phenylpyridine) coformers.

Synthesis of oxidized carboxymethyl cellulose-chitosan and its composite films with SiC and SiC@SiO nanoparticles for methylene blue dye adsorption.

The cationic methylene blue (MB) dye sequestration was studied by using oxidized carboxymethyl cellulose-chitosan (OCMC-CS) and its composite films with silicon carbide (OCMC-CS-SiC), and silica-coated SiC nanoparticles (OCMC-CS-SiC@SiO). The resulting composite films were characterized through various analytical techniques, including Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Thermogravimetric analysis (TGA), Field emission scanning electron microscopy (FESEM), and energy-dispersive X-ray spectroscopy (EDS). The dye adsorption properties of the synthesized composite films were comprehensively investigated in batch experiments and the effect of parameters such as contact time, initial dye concentration, catalyst dosages, temperature, and pH were systematically evaluated.

Dual-drug amorphous formulation of gliclazide.

Amorphization is a well-established strategy to enhance the dissolution properties of poorly water-soluble drugs. However, the amorphous state is inherently unstable toward recrystallization. Coamorphous systems of a drug and a small-molecule excipient or of two complementary drugs often show an enhanced stability.

Investigation of the formation of drug-drug cocrystals and coamorphous systems of the antidiabetic drug gliclazide.

The antidiabetic drug gliclazide (GLZ) has a slow absorption rate and a low bioavailability due to its poor solubility. GLZ is often prescribed along with an antihypertensive, as many diabetic patients have coexistent hypertension. Cocrystallization and coamorphization are attractive strategies to enhance dissolution rates and to reduce the number of medications a patient has to take.