Benchmarking the Solubility Enhancement and Storage Stability of Amorphous Drug–Polyelectrolyte Nanoplex against Co-Amorphous Formulation of the Same Drug

Enhancing water solubility of phytosterols through Co-amorphization with food-grade coformers

Phytosterols (PS) offer significant health benefits in human diet, but its poor solubility limits its effectiveness and application. This study explored enhancing PS solubility by testing thirteen food-grade coformers, three preparation methods and proportions screening to obtain the optimal formulation. Nicotinamide (Nic) was identified as the most effective coformer. A 20:1 (w/w) PS-Nic co-amorphous (CM) mixture, prepared via freeze-drying, achieved a solubility of 1536.4 μg/mL, significantly higher than pure PS. X-ray diffraction and differential scanning calorimetry confirmed the amorphous state of the mixture. Fourier-transform infrared, Raman, and 1H NMR spectroscopies, along with molecular dynamics simulations, revealed strong intermolecular interactions between PS and Nic. The PS-Nic CM demonstrated up to 60% in vitro dissolution and release within 2 h and maintained stable after storage at 4 °C for 6 months and under accelerated conditions equivalent to 10 months at room temperature. In sum, the crystal structure of PS was altered, and formed a co-amorphous system by using Nic as the optimal ligand via lyophilization to increase solubility. These findings suggest that the PS-Nic CM system has potential applications in functional foods, offering a feasible strategy to enhance the bioavailability of PS.

Current Techniques of Water Solubility Improvement for Antioxidant Compounds and Their Correlation with Its Activity: Molecular Pharmaceutics

The aqueous solubility of a drug is important in the oral formulation because the drug can be absorbed from intestinal sites after being dissolved in the gastrointestinal fluid, leading to its bioavailability. Almost 80% of active pharmaceutical ingredients are poorly water-soluble, including antioxidant compounds. This makes antioxidant activity inefficient in preventing disease, particularly for orally administered formulations. Although several investigations have been carried out to improve the solubility of antioxidant compounds, there is still limited research fully discussing the subject. Therefore, this study aimed to provide an overview and discussion of the issues related to the methods that have been used to improve the solubility and activity of antioxidant compounds. Articles were found using the keywords "antioxidant" and "water solubility improvement" in the Scopus, PubMed, and Google Scholar databases. The selected articles were published within the last five years to ensure all information was up-to-date with the same objectives. The most popular methods of the strategies employed were solid dispersion, co-amorphous, and nanoparticle drug delivery systems, which were used to enhance the solubility of antioxidant compounds. These investigations produced impressive results, with a detailed discussion of the mechanism of improvement in the solubility and antioxidant activity of the compounds developed. This review shows that the strategies used to increase the solubility of antioxidant compounds successfully improved their antioxidant activity with enhanced free radical scavenging abilities.

Downstream Processing of Amorphous and Co-Amorphous Olanzapine Powder Blends

The work evaluates the stability of amorphous and co-amorphous olanzapine (OLZ) in tablets manufactured by direct compression. The flowability and the compressibility of amorphous and co-amorphous OLZ with saccharin (SAC) and the properties of the tablets obtained were measured and compared to those of tablets made with crystalline OLZ. The flowability of the amorphous and mostly of the co-amorphous OLZ powders decreased in comparison with the crystalline OLZ due to the higher cohesiveness of the former materials. The stability of the amorphous and co-amorphous OLZ prior to and after tableting was monitored by XRPD, FTIR, and NIR spectroscopies. Tablets presented long-lasting amorphous OLZ with enhanced water solubility, but the release rate of the drug decreased in comparison with tablets containing crystalline OLZ. In physical mixtures made of crystalline OLZ and SAC, an extent of amorphization of approximately 20% was accomplished through the application of compaction pressures and dwell times of 155 MPa and 5 min, respectively. The work highlighted the stability of amorphous and co-amorphous OLZ during tableting and the positive effect of compaction pressure on the formation of co-amorphous OLZ, providing an expedited amorphization technique, given that the process development-associated hurdles were overcome.