Investigation on co-solvency, solvent effect, Hansen solubility parameter and preferential solvation of fenbufen dissolution and models correlation

Health is the greatest wealth: Quest for a diagnostic check for thermochemistry of pure drug compounds

The development of pharmaceutical formulations and the optimisation of drug synthesis are not possible without knowledge of thermodynamics. At the same time, the quantity and quality of the available data is not at a level that meets modern requirements. A convenient diagnostic approach is desirable to assess the quality of available experimental thermodynamic data of drugs. A comprehensive set of available data on phase transitions of profens family drugs was analysed using new complementary measurements and structure-property correlations. The consistent sets of solid-gas, liquid-gas and solid-liquid phase transitions were evaluated for twelve active pharmaceutical ingredients based on alkanoic acid derivatives and recommended for the calculations of the pharmaceutical processes. A "centerpiece approach" proposed in this work helped to perform the "health check" of the thermochemical data. The evaluated data on the sublimation enthalpies were used to derive the crystal lattice energies of the profens and to correlate the water solubilities with the sublimation vapour pressures and molecular parameters. A "paper-and-pen" approach proposed in this work can be extended to the diagnosis of "sick" or "healthy" thermodynamic data for drugs with a different structure than those studied in this work.

Measurement and correlation of solubility data for deferiprone in propylene glycol and 2-propanol at different temperatures

This investigation dealt with the thermodynamic properties, saturated solubility values, and solvation behavior of deferiprone as an oral iron chelator agent in non-aqueous mixtures of propylene glycol and 2-propanol using experimental measurements and mathematical correlations. The solubility of deferiprone demonstrated a positive correlation with both temperature and propylene glycol mass fraction. Four mathematical models were employed to correlate the solid-liquid equilibrium data, and the low mean relative deviation values of less than 3.6% illustrate the good agreement of computed data with the experimental data. The apparent thermodynamic behavior of deferiprone dissolution was also investigated according to van't Hoff and Gibbs equation.

Solid-Liquid Equilibrium Behavior and Solvent Effect of Gliclazide in Mono- and Binary Solvents

The solubility data of gliclazide in 10 mono-solvents (1,2-dichloroethane, 1,4-dioxane, 2-methoxyethanol, n-propyl acetate, isopropyl acetate, n-butyl acetate, pentyl acetate, dimethyl sulfoxide (DMSO), N,N-dimethylacetamide (DMA), and 2-butanone) and one kind of binary solvent (DMA + water) were measured between 278.15 and 323.15 K under atmospheric pressure by the gravimetric method. The Hansen solubility parameters and the KAT-LSER equation were used to investigate the solubility order and the influence of solvent effects on solubility. The experimental data were correlated by six thermodynamic models (the λh model, the Yaws model, the Apelblat model, the Jouyban model, the modified Jouyban-Acree model, and the Sun model). The results show that all of these models can correlate the experimental data well. Among them, the Apelblat model is the most suitable for correlating the solubility data of gliclazide in mono-solvents and binary solvents.

Hollow Fiber Membrane for Organic Solvent Nanofiltration: A Mini Review

Organic solvents take up 80% of the total chemicals used in pharmaceutical and related industries, while their reuse rate is less than 50%. Traditional solvent treatment methods such as distillation and evaporation have many disadvantages such as high cost, environmental unfriendliness, and difficulty in recovering heat-sensitive, high-value molecules. Organic solvent nanofiltration (OSN) has been a prevalent research topic for the separation and purification of organic solvent systems since the beginning of this century with the benefits of no-phase change, high operational flexibility, low cost, as well as environmental friendliness. Especially, hollow fiber (HF) OSN membranes have gained a lot of attention due to their high packing density and easy scale-up as compared with flat-sheet OSN membranes. This paper critically reviewed the recent research progress in the preparation of HF OSN membranes with high performance, including different materials, preparation methods, and modification treatments. This paper also predicts the future direction of HF OSN membrane development.