Solubility of celecoxib in N -methyl-2-pyrrolidone + 2-propanol mixtures at various temperatures

Strategies to Improve the Transdermal Delivery of Poorly Water-Soluble Non-Steroidal Anti-Inflammatory Drugs

The transdermal delivery of non-steroidal anti-inflammatory drugs (NSAIDs) has the potential to overcome some of the major disadvantages relating to oral NSAID usage, such as gastrointestinal adverse events and compliance. However, the poor solubility of many of the newer NSAIDs creates challenges in incorporating the drugs into formulations suitable for application to skin and may limit transdermal permeation, particularly if the goal is therapeutic systemic drug concentrations. This review is an overview of the various strategies used to increase the solubility of poorly soluble NSAIDs and enhance their permeation through skin, such as the modification of the vehicle, the modification of or bypassing the barrier function of the skin, and using advanced nano-sized formulations. Furthermore, the simple yet highly versatile microemulsion system has been found to be a cost-effective and highly successful technology to deliver poorly water-soluble NSAIDs.

Application of PC-SAFT EOS for Pharmaceuticals: Solubility, Co-Crystal, and Thermodynamic Modeling

In this study, the applicability of the perturbed chain statistical associating fluid theory (PC-SAFT) was evaluated for pharmaceutical compounds. For this purpose, the parameters of the PC-SAFT equation of state (EOS) were regressed by applying the experimental solubility data of 54 pharmaceuticals in pure solvents. The reported errors for train and test data show the suitability of the PC-SAFT EOS. The applicability of the PC-SAFT EOS was explored by its prediction accuracy for the ternary system of medicine in solvent mixtures. The model errors were 23 and 26% for two ternary systems of salicylic acid and lidocaine HCl in solvent mixtures of ethanol and water, respectively. The co-crystal formation of salicylic acid-sulfamethazine in methanol was investigated by the PC-SAFT EOS. Finally, the reaction and crystallization sections for acetaminophen production from p-aminophenol were simulated by accompanying the PC-SAFT EOS and equilibrium assumption. The purification efficiencies for acetaminophen were obtained to be 93-98% for different temperatures.

Significant Increase in the Solubility of Celecoxib in Presence of Some Deep Eutectic Solvents as Novel Sustainable Solvents and the Thermodynamic Analysis of These Systems

Background: Deep eutectic solvents (DESs) exist a wide variety of potential and existing applications. Based on the fact that the choline chloride (ChCl) is a complex B vitamin and widely used as food additive, the choline-based DESs are generically regarded as being harmless and non-toxic. In this regard, the low aqueous solubility of celecoxib (CLX) have been increased by use of DESs as neoteric class of solvents at T = (298.15 to 313.15) K. Methods: DESs were prepared by combination of the ChCl/EG, U and G with the molar ratios: 1:2 and ChCl/MA with 1:1. The shake flask method was used to measure the solubility of CLX in the aqueous DESs solutions at different temperatures. Results: The solubility of the CLX increased with increasing the weight fraction of DESs. The observed solubility data was subjected to evaluate the relative performance of a number of models including Apelblat, Yalkowsky and Jouyban–Acree models for their correlation efficacy. Moreover, the apparent dissolution enthalpy, entropy and Gibbs free energy were obtained from the experimental solubility values. Conclusion: It was found that the solubility data was satisfactorily fitted using the mentioned models at different temperatures. The dissolution process of CLX in the studied solvent mixtures within investigated temperature range was endothermic, and the driving mechanism is the positive entropy.