Mechanical Testing of Alginate Hydrogel Composites with Chlorinated Bioglass for Bone Regeneration

• Grant number: 25/08093-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2025
• End date: August 31, 2026
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Alexandre Luiz Souto Borges
• Grantee: Fabrício Seles da Silva
• Host Institution: Instituto de Ciência e Tecnologia (ICT). Universidade Estadual Paulista (UNESP). Campus de São José dos Campos. São José dos Campos , SP, Brazil

Abstract

Bone regeneration is an essential process in various clinical conditions, and biomaterials play a fundamental role in this context. Bioactive glasses, particularly S53P4, stand out due to their bioactive properties, releasing calcium and forming apatite without increasing pH, thus preserving cell viability. However, conventional materials face limitations in dissolution and bioactivity. Chlorinated bioactive glass emerges as an effective alternative, promoting the controlled release of ions that stimulate osteogenesis and angiogenesis without compromising cell health. This project aims to characterize the mechanical properties, compressive and tensile strength, swelling, and contact angle of an alginate hydrogel composite with chlorinated bioactive glass (S53P4) at different concentrations. The alginate composites will be prepared with varying proportions of chlorinated bioactive glass (5%, 10%, 20%). The chlorinated bioactive glass will be produced using the sol-gel technique. Subsequently, hydrogels based on gelatin, alginate, and calcium chloride will be produced. The process will involve using 10 mL of distilled water at 55°C, to which 0.3% CaCl2, 0.5% type A porcine skin gelatin, and 5% sodium alginate will be added. This solution will then be stirred for 20 minutes to achieve the appropriate consistency. The bioactive glass will be weighed and added following the proportions of 5%, 10%, and 20% of the volume, and maintained under magnetic stirring for an additional 20 minutes until the particles are fully dissolved. After material preparation, the solutions will be placed in 10 mL disposable plastic syringes fitted with a 22G irrigation needle and positioned in a 3D printer for the production of specimens for mechanical and physical tests. Compression tests, tensile tests, contact angle measurements, and swelling tests will be conducted on the gel without bioactive glass (control group) and on the hydrogel with the three different concentrations of S53P4 bioactive glass in its composition. It is expected to determine a hydrogel-to-bioactive glass ratio that provides optimal mechanical properties for improved application in bone regeneration.