Optimized Fabrication and Enhanced Flexural Properties of PCL/F-BG Nanocomposites for Hard Tissue Engineering

To achieve bio-composites with optimal mechanical properties while considering biological aspects, neat PCL and PCL nanocomposites incorporating 15%, 27%, 30%, 32%, and 45% APTES-functionalized bioactive glass (F-BG) were developed using an innovative solvent casting method. The predominant particle size of 55 nm ensured well-distributed, non-agglomerated particles within the composites. Fine flexural specimens were prepared via melt molding with a hot press for mechanical property evaluations. Flexural testing revealed that the PCL/32% F-BG samples exhibited the highest flexural strength (25.8 MPa), whereas the PCL/45% F-BG samples showed the greatest flexural elastic modulus (1793 MPa). Consequently, PCL/32% F-BG was identified as the sample with optimal mechanical properties. Microstructural analysis of the samples and the fractography analysis were performed using FESEM and SEM, confirming the well-dispersed BG nanoparticles within the polymer matrix. To ensure comprehensive evaluations beyond mechanical properties, hydrophilicity tests, weight loss measurements, absorbed water, and pH changes were conducted over 3, 7, 14, and 28 days within the framework of degradation tests. Additionally, cytotoxicity tests were conducted over 24, 48, and 72 hours using mouse embryonic fibroblast cells (NIH3T3), enabling thorough assessments.