The CO ₂ release behavior, i.e. , “post-gelation condition,” affects the degree of cross-linking, an essential parameter for determining hydrogel properties.

Stomatitis induced by radiation therapy or cancer chemotherapy is a factor in sleep disorders and/or eating disorders, markedly decreasing patient quality of life. In recent years, disintegrating oral films that are easy to handle have been developed; therefore, we focused on the formulation of these films. We prepared an adhesive film for the oral cavity using xyloglucan (Xylo), which is a water-soluble macromolecule. We used loperamide, which has been reported to relieve pain caused by stomatitis effectively, as a model drug in this study. Films were prepared from Xylo solutions (3% (w/w)) and hypromellose (HPMC) solutions (1% (w/w)). Xylo and HPMC solutions were mixed at ratios of 1 : 1, 2 : 1, or 3 : 1 for each film, and films 2×2 cm weighing 3 g were prepared and dried at 37°C for 24 h. Physicochemical properties such as strength, adhesiveness, disintegration behavior, and dissolution of loperamide from films were evaluated. Films prepared from Xylo solution alone had sufficient strength and mucosal adhesion. On the other hand, films prepared from a mixture of Xylo and HPMC were inferior to those made from Xylo, but showed sufficient strength and mucosal adhesion and were flexible and easy to handle. The films prepared in this study are useful as adhesion films in the oral cavity.

In the present study, to prepare dispersoids with high dispersion stability that can be used as mouthwash, ground mixtures of commercial rebamipide (RB) tablets and hydroxypropyl cellulose (HPC-SSL) samples were prepared by dry milling. The physicochemical properties of the ground mixture of HPC-SSL and the powder obtained from the preliminary ground RB tablets were then compared. The dispersoids' physicochemical properties, dispersion stability, retention, and diffusiveness to the mucosal surfaces were evaluated in vitro. By co-grinding with HPCSSL, RB transformed into fine particles around 303.6 - 361.5 nm that tended to prevent particle agglomeration in solution over time. The sample microparticles formed with HPC-SSL also avoided agglomeration on the mucosal surface for 24 h, improving oral retention. Furthermore, the ground mixture of HPC-SSL and the powder obtained from the preliminary ground RB tablets dispersed and permeated the mucus gel layer on the mucosal surface (24.2 %) but not the mucosal cells, indicating that RB remained on the mucosal surface. These results suggest that ground mixtures of commercial rebamipide (RB) tablets and hydroxypropyl cellulose (HPC-SSL) samples can be applied as a powdered suspension preparation because they showed high dispersion stability and oral mucosal retention.

This study aimed to prepare films using Xyloglucan (Xylo) and tea extract (TE) to treat aphthous stomatitis without causing discomfort. Xylo, which gelates by adding polyphenol, was used as a gelation agent, and TE, which contains epigallocatechin-3-gallate (EGCG) with antioxidant properties, was used as an active pharmaceutical agent. Two kinds of films, hydrogel and xerogel films, were prepared by mixing various amounts of Xylo and TE. Their gelling behavior and physicochemical properties were evaluated. The sol-gel transition temperature increased with increased TE content, and the rupture strength of the films increased with increasing Xylo and TE concentrations. Rapid water absorption and high adhesiveness were observed during the reconstruction process from the xerogel to the hydrogel. The concentrations of Xylo and TE controlled the formulations' physicochemical properties and the EGCG release rate. These results concluded that the xerogel prepared by using Xylo and TE could be applied as an oral mucosal adherent film formulation.

Ulcerative colitis (UC) is a chronic inflammatory bowel disease characterized by abdominal pain and diarrhea. Although 5-aminosalicylic acid (5-ASA) enemas are widely used, conventional formulations can result in rectal leakage and poor retention, substantially impairing the therapeutic efficacy and quality of life (QOL) of patients. To address these limitations, in this study, we developed a thermoresponsive and mucoadhesive dual-functionality enema system by combining poloxamer with carbopol (CP). This study optimized a thermoresponsive and mucoadhesive rectal gel formulation for 5-ASA and evaluated its physicochemical properties and therapeutic efficacy in experimental ulcerative colitis. The formulation exhibited a gelation temperature of 30-35 °C, indicating its suitability for situ gel formation in the colon. The ¹H NMR analysis confirmed minimal interactions between 5-ASA and the polymers. Increasing the CP concentration markedly delayed drug release, likely due to enhanced network entanglement within the gel. Ex vivo evaluation using porcine colonic mucosa indicated reduced leakage and improved adhesion compared with a commercial formulation. Furthermore, in vitro studies using Caco-2 cells showed enhanced retention of the active compounds. These findings indicate that the proposed system enables injectable administration, in situ gelation, strong mucosal adhesion, and gradual release of 5-ASA while maintaining enhanced mucoadhesion and rectal retention, thereby improving retention and therapeutic potential. Furthermore, the administration of the formulation to rats with UC led to a significantly higher anti-inflammatory effect. Thus, the developed approach represents a promising strategy for enhancing treatment efficacy and patient compliance in ulcerative colitis.

Consideration of drug usability characteristics is important during the design process. Although many wound management products have been developed in recent years, there are few studies on their usability. We investigated the needs and characteristics of wound management products required by medical professionals, so as to consider these in future development projects. Semi-structured interviews were conducted in a group of healthcare professionals. Interview responses were analyzed based on thematic analysis. Four themes common to all facilities were secondary wounds, adaptability of materials, convenience, and physicochemical properties. Economic efficiency of medical care was found to be considered only at the hospital, and quality of life of patients was found to be considered only at the home palliative care clinic. Requirements for wound management products can be affected by participants’ roles and their facility settings. However, there were needs common to all fields that all wound management products should aim to incorporate.