Yuichi Tozuka

Gelation film-coating (GFC) technology has attracted attention as a strategy to improve the swallowability and taste masking of oral solid dosage forms; however, its application to mini-tablets remains challenging because of their high specific surface area and manufacturing limitations. This study aimed to develop a simple and scalable GFC formulation for mini-tablets using standard film-coating equipment. A poly(vinyl alcohol)/polyethylene glycol graft copolymer (PVAPEG) was used as the base polymer, and various thickening agents were screened to optimize the gel formation, disintegration behavior, and surface adhesion. The formulations were evaluated in terms of maximum extrusion stress, disintegration time, dissolution performance, pharmacokinetics, sensory characteristics, and stability. Among the tested formulations, xanthan gum (XG) provided an optimal balance between reduced adhesion and controlled disintegration. GFC mini-tablets containing PVAPEG and XG significantly improved swallowability and bitterness masking compared to uncoated formulations, while maintaining rapid drug dissolution comparable to that of the reference product. Bioequivalence with the marketed product was confirmed, and accelerated stability studies demonstrated excellent stability of the formulation. These findings indicate that GFC mini-tablets based on PVAPEG and XG represent a robust and scalable formulation strategy that enhances patient acceptability without compromising the pharmaceutical performance.

Supraparticles (SPs) are secondary particles formed through nanoparticle self-assembly with porous architectures and bioinspired structural features suitable for drug delivery applications. Although binder-mediated structural control influences SP assembly, how different loaded drugs systematically alter amyloid nanofibril (ANF) and SP structures remains unclear. In this study, neutral, basic, and acidic model drugs—acetaminophen (ACP), fluconazole (FCZ), and proglumide (PGM), respectively—were incorporated into spray-dried SPs composed of silica nanoparticles (SiNPs) and ANFs to investigate the effects of drug properties on SP structure and release behavior. All drugs exhibited nearly 100% loading efficiency, and powder X-ray diffraction analysis revealed that they were in an amorphous state within the SPs. ACP- and FCZ-loaded SPs maintained their characteristic ANF-induced wrinkled morphology, whereas PGM-loaded SPs exhibited a pronounced loss of wrinkling at pH 2, indicating that acidic drugs can disrupt ANF-mediated assembly during SP formulation. Drug release studies further showed that ANFs suppressed the initial burst release and slowed the overall release by restricting diffusion pathways within the SP structures. This suppression was the most pronounced in PGM-loaded SPs, likely owing to drug retention within the assembled ANF domains. These findings demonstrate that drug acid–base properties critically modulate SP morphology and release behavior, highlighting the importance of drug–biomaterial interactions in designing SP-based delivery platforms.

Magnetite (Fe3O4) nanoparticles are widely used as functional magnetic materials, characterized by their ferromagnetism, biocompatibility, and electrical conductivity. Because these properties strongly depend on particle size and morphology, controlling nucleation and growth is essential. The glycothermal method has emerged as a versatile route for synthesizing metal oxide nanoparticles with tunable shapes, and we previously demonstrated that morphology control can be achieved without additives simply by varying the solvent system. In this study, we investigated the influence of synthesis temperature and precursor concentration on the additive-free glycothermal formation of Fe3O4, interpreted through the framework of the LaMer model. Spherical secondary particles with diameters of 277–350 nm were formed, comprising primary nanoparticles whose sizes varied according to the reaction conditions. Electrical conductivity exhibited a strong negative correlation with specific surface area (r = −0.88). To elucidate this behavior, we compared crystalline size with the diameter derived from specific surface area, providing insights into the internal microstructure and packing density of the aggregates. Transmission electron microscopy analysis revealed that nanoscale roughness, correlation length, and Fourier components associated with different morphological length scales remained unchanged across all synthesis conditions. These results demonstrate that microstructural control in magnetite assemblies is crucial for tuning their electrical properties and highlight the potential of additive-free glycothermal synthesis for designing Fe3O4-based functional materials.

Correction for ‘Physically stable cyclodextrin metal–organic frameworks formed via a drug-assisted amorphous to crystal phase transition’ by Ryoma Tanaka et al. , CrystEngComm , 2025, 27 , 7121–7127, https://doi.org/10.1039/d5ce00755k.

Current methods for evaluating the photostability of pharmaceutical drugs typically separate the irradiation step from the analytical process, making it challenging to observe real-time photodegradation during irradiation. The use of HPLC equipped with UV and/or MS detectors, which are commonly used for quantitative analysis, requires considerable time to establish optimal conditions, and employs organic solvents, which are harmful to both the environment and the analyst. The aim of this study is to investigate the effectiveness of isothermal differential scanning calorimetry (DSC) equipped with a UV probe (photo-DSC) for evaluating the photostability of pharmaceutical drugs in the solid state. The response to light irradiation varies for different drugs, with some drugs exhibiting a thermal history showing endothermic behavior. To confirm the results of the endothermic reaction in photo-DSC, the percentage of the drug remaining after photo-irradiation was quantified using HPLC. Drugs that exhibited endothermic peaks consistently showed a decrease in residuals due to the photolysis reaction. In this study, we highlight the effectiveness of photo-DSC in evaluating the susceptibility of different drugs to photodegradation.