Physico-mechanical and antimicrobial performance of green nanocomposite Ca/Bentonite/Chitosan

The need to balance biomaterials' mechanical and biological properties is driving the development of scaffolds for tissue engineering applications. A scaffold composed of Eggshell calcium (Ca), exfoliated bentonite (EXF-BE), and Chitosan (CS) was synthesized and studied as a bone tissue scaffold. The highest value of the surface area was 134.6 m²/g for the Ca/EXF-BE/CS with an average pore width of 44.5 Å. The mechanical properties of EXF-BE were enhanced with Ca and CS addition, which is clear in the values of ultimate tensile strength (σ _uts ) 15.38 MPa, 16.19 MPa, and 17.84 MPa; Toughness 1.435± 0.23 MJ/m ³ , 1.713  MJ/m ³ , 2.067 MJ/m ³ , and strain at breakdown of about 28.5, 28.69 ± 0.3%, and 30.1 ± 0.33% for EXF-BE, Ca/EXF-BE, and Ca/EXF-BE/CS, respectively. Antimicrobial properties, assessed by the disc diffusion method, showed inhibition zones of 27.13, 21.25, 19.25, and 20.88 mm against E. coli and S. aureus, demonstrating promising multifunctional properties.