Gas Permeability of Mold during Freezing Process Alters the Pore Distribution of Gelatin Sponge and Its Bone-Forming Ability

Effect of mold shape on the microstructure of gelatin sponges for tissue engineering applications

Gelatin sponges have been used in several medical applications including tissue replacement, scaffolds, and hemostasis. Each application requires specific parameters that are tuned by the porosity of the sponges. Therefore, changes in the porosity profile of the sponges would change the sponge behavior. In this study, a gelatin solution was prepared and crosslinked with glutaraldehyde. Afterward, the solution was poured into three different mold structures with different volumes and frozen at a constant freezing rate. Each mold was investigated for its physical characteristics including swelling, degradation, porosity, crystallinity, and mechanical compression. Cube-molded gelatin sponges demonstrated high swelling capacity, degradation rate, and porosity while exhibiting low crystallinity, yield strength, and elasticity. These characteristics are suitable for hemostatic application and tissue regeneration. Therefore, it is recommended to freeze dry gelatin sponge in cuboid-shaped dimensions, for research or industry, to control the porosity and crystallinity of the sponge for the best result in biomedical applications.

Special Issue: Advances in Dental Bio-Nanomaterials

Recent advances in dental materials involving the development of various biomaterials have been reported. Accordingly, clinicians must incorporate the new dental materials in their practice to respond to the increasing needs of patients. Nanotechnology is defined as a science that deals with nanoscale materials. The use of nanomaterials is gaining popularity in the dental industry for processing and manipulating nanoscale substances in modern dentistry. In this special issue, we invited the submission of several research papers on the development of dental materials. In this general discussion, we briefly explain the relevant research reports with an aim that developments in this field will contribute toward the development of dental care in the future.

Lyophilized Emulsions in the Form of 3D Porous Matrices as a Novel Material for Topical Application

Researchers are constantly searching for innovations that can be applied to the cosmetic industry. Production of porous materials stored in a lyophilized form and swollen directly before use may be beneficial considering their facilitated packaging, transport and storage. In this study, we propose porous materials based on sodium alginate, gelatin, glycerol and lipids (cottonseed oil and beeswax) obtained by freeze-drying and cross-linking. Material composition with the most promising properties was modified by the addition of PLA microparticles with Calendula officinalis flower extract. The structure and properties of obtained porous materials were analyzed. ATR-FTIR, mechanical properties, residual moisture content, porosity and density were assessed, as well as swelling properties and degradation after their cross-linking. The loading capacity and in vitro release of Calendula officinalis flower extract were performed for samples with incorporated PLA microparticles containing plant extract. The modification of the composition and fabrication method of materials significantly influenced their physicochemical properties. The selected plant extract was successfully incorporated into polymeric microparticles that were subsequently added into developed materials. Prepared materials may be considered during designing new cosmetic formulations.